BIOLOGY FORM THREE QUESTIONS AND
SHORT ANSWERS
QUESTION:
The
Components of the Central Nervous System and their Functions
ANSWERS: Some
parts and (functions) of the brain are: Cerebellum (concerned with long-term
memory, co-ordination, etc); Cerebrum (controls emotions, hearing, vision,
personality, etc); Medulla oblongata (controls involuntary activities such as
breathing, heartbeat, etc); Spinal cord (transmission of neural signals between
the brain and the rest of the body, controls numerous reflexes).
QUESTION:
The
Structures of Human Skeleton
ANSWERS: The
human skeleton is the internal framework of the body. It can be divided into
the axial skeleton and the appendicular skeleton. The axial skeleton is formed
by the vertebral column, the rib cage, the skull and other associated bones.
The appendicular skeleton, which is attached to the axial skeleton, is formed
by the shoulder girdle, the pelvic girdle and the bones of the upper and lower
limbs.
QUESTION:
The
Importance of Movement in Animals and Plants
ANSWERS: Movement
and locomotion actions are important to animals and plants because they enable
the animals to (a) escape from danger; (b) move to better climatic conditions;
(c) search for food; and (d) find mate. They also (e) aid in animal or insect
pollination; and (f) enable plant shoots to move towards light and roots
towards water and nutrient sources so as to carry out photosynthesis.
QUESTION:
Causes
Effects and Preventive Measures of Muscles Cramps
ANSWERS: Causes
of muscle pain: muscle injury, dehydration, low Ca, K, Na, and Mg, and low
blood supply. Also spinal nerve compression, alcoholism, pregnancy, kidney
failure, hypothyroidism, or low thyroid gland function can cause muscle cramps.
Effects: muscle pain, may interrupt sleep, or make it difficult to walk.
Prevention: Ca, K and fluid intake, and stretching or warming up before
exercise.
QUESTION:
Types
of Muscles
ANSWERS: There
are 3 types of muscles: (1) Cardiac muscle – involuntary, striated muscle that
forms the walls of the heart, specifically the myocardium. (2) Skeletal
(voluntary) muscle – occurs in muscles which are attached to bones by bundles
of collagen fibres known as tendons. (3) Smooth (involuntary/visceral) muscles
located in walls of hollow visceral organs, except the heart.
QUESTION:
The
Concept of Movement in Plants (Movement of Curvature)
ANSWERS: Generally,
plants do not show locomotion (movement of the entire organism). However,
movement of individual plant organs is possible, modified by sensitivity of the
plant to external stimuli. Plant organs move toward scarce resource or
otherwise secure food, or use movement as an adaptation to escape or minimize
injury from harmful external factors, or ensure development.
QUESTION:
The
Concept of Tropic and Nastic Responses
ANSWERS: Tropisms
are growth responses of plants that result in curvatures of plant organs toward
or away from certain stimuli. Important tropisms in plants include
phototropism, gravitropism, hydrotropism and thigmotropism. Nastic responses
are non-directional responses to the intensity of a stimulus. Nastic responses
include thigmonasty, thermonasty, hydronasty, etiolation, and photonasty.
QUESTION:
The
Importance of Tropic and Nastic Responses
ANSWERS: Tropic
and nastic responses allow plants to survive, grow, develop and reproduce. That
is, they enable plants to anchor in the soil, absorb water and minerals, and
expose leaves to sunlight for photosynthesis; and also help in plant support,
enable the plant to survive by avoiding contact with harmful chemicals, trap
and digest insects, and facilitate the fertilization process in flowering
plants.
QUESTION:
The
Difference between Simple Reflex and Conditioned Reflex Action
ANSWERS: Differences:
simple reflex action/conditioned reflex action respectively: it requires only
one stimulus/it involves more than one stimuli; it mostly involves the spinal
cord/involves the brain; it is an immediate action (no time to learn)/it
requires time to learn; it is inborn behaviour/it is an acquired behaviour
(learned behaviour); action starts by muscle receptor cells/it starts in the
brain
QUESTION:
The
Functions of Sense Organs and their Adaptive Features
ANSWERS: Some
functions of the named sense organs are: SKIN (protection, sensation,
excretion, storage of fat, synthesis of vitamin D, and body temperature
regulation); EAR (hearing and maintaining balance and posture); EYES (vision);
TONGUE (vital in tasting and chewing food and in speech); and NOSE (smelling and
breathing). Each sense organ has adaptive structures which make it fit for its
function(s).
QUESTION:
Proper
Ways of Handling and Using Drugs
ANSWERS: Proper
use and handling of drugs include: avoiding taking any drug without
prescription by the doctor, staying away from peer pressures and drug addicts,
keeping oneself busy with an activity, reporting any drug abuse or trafficking,
youth counselling, rehabilitation of addicts, avoiding overdose of
over-the-counter drugs, finishing the prescribed doses, and keeping drugs out
of children’s reach.
QUESTION:
The
Concept of Movement and Locomotion
ANSWERS: Locomotion
is the movement of an entire organism from one place to another. The locomotion
of human or other animals is accomplished through walking, running, leaping,
jumping, gliding, flying, or swimming. Movement only involves part of an
organism’s body. Examples of movements include moving a hand, leg, head or any
part of the body. Both movement and locomotion spend energy stored in the body.
QUESTION:
Types
of Movement Exhibited by Plants
ANSWERS: Tropic
movements are movements of curvature that respond to the direction of the
external stimulus. Important tropisms include phototropism, geotropism,
hydrotropism, chemotropism and thigmotropism. Nastic movements are plant
movements independent of the direction of the external stimulus. Nastic
movements include epinasty, hyponasty, hydronasty, nyctinasty, seismonasty, and
thigmonasty.
QUESTION:
Experiments
to Investigate Movement in Plants
ANSWERS: Phototropism
(cover a potted plant with a box and cut a small hole in the side of the box).
Geotropism (uproot a health plant and lay it flat on soil for 5 days and keep
irrigating the soil). Hydrotropisms (plant a seed some distance away from water
source and observe the direction of root growth). Thigmotropism (fix a stick
close to bean plant). Seismonasty (touch leaves mimosa pudica).
QUESTION:
Process
of Fertilization in Flowering Plants
ANSWERS: During
growth of the pollen tube, the generative nucleus, behind the tube nucleus,
divides by mitosis to produce 2 male haploid sperm nuclei. The pollen tube
enters the ovule through the micropyle and penetrates the embryo sac wall.
Then, the tip of the tube bursts open, the tube nucleus disintegrates, creating
a passage for the male nuclei and what follows is called double fertilisation.
QUESTION:
The
Functions of the Major Components of the Human Skeleton and their Adaptations
ANSWERS: The
functions of skeleton are: (a) support (point for muscle attachment); (b)
protection (skull protects brain, vertebrae protect the spinal cord, and the
ribcage and breast bone protect the heart and lungs); (c) locomotion (skeleton
as a lever system allows movement); (d) storage of minerals (Ca & P); (e)
blood formation (red bone marrow produces red blood cells and phagocytes); (f)
feeding.
QUESTION:
Causes
and Effects of Drug Addiction
ANSWERS: Some
causes of drug abuse include misuse of medical drugs, peer pressure, and lack
of life and social skills. Effects of drug abuse and addiction include
dependency, mental confusion, heart failure, disruption of normal body
functions, aggressiveness, crime and violence, spread of contagious diseases
through sharing needles, misuse of money on drugs, body deterioration, birth
defect, and death.
QUESTION:
Advantages
and Disadvantages of Division Angiospermophyta
ANSWERS: Advantages
of angiosperms: Human food; Livestock feed; Wood (for furniture, charcoal,
paper); Textile (textile fibres); Medicine (medicinal herbs); Produce flowers
for sale; Forestry (study); Ecology (animal habitats) Climate modification; and
Ecotourism. Disadvantages: Toxins (some plants are poisonous when eaten by
human and other animals). Drugs (misused as drugs); Weeds (some are bad weeds).
QUESTION:
General
and Distinctive Features of the Division Coniferophyta
ANSWERS: General
characteristics of Division Coniferophyta: vascular; mostly evergreen trees and
shrubs; xeromorphic; have secondary growth; reproduce sexually by seeds;
world's tallest plants (1-100m); have alteration of generation; Distinctive
features: their seeds are not enclosed in ovary, but in cones; have needle-like
leaves with a thick cuticle; and they are non-flowering but seed bearing
plants.
QUESTION:
Causes
and Effects of Drug Addiction
ANSWERS: Some
causes of drug abuse include misuse of medical drugs, peer pressure, and lack
of life and social skills. Effects of drug abuse and addiction include
dependency, mental confusion, heart failure, disruption of normal body
functions, aggressiveness, crime and violence, spread of contagious diseases
through sharing needles, misuse of money on drugs, body deterioration, birth
defect, and death.
QUESTION:
Preventive
and Control Measures of Drug Abuse
ANSWERS: Some
preventive and control measures of drug abuse include: early detection and
treatment of addicts, motivating addicts to make up for detoxification,
inculcating good manners to youth, community education, enforcing laws and
regulations against control and supply of drugs, educating pupils and students
about effects of drugs, and using rehabilitated drug users as campaigners
against drug abuse.
QUESTION:
The
Components of the Peripheral Nervous System and Their Functions
ANSWERS: PNS
has two components: somatic nervous system (SNS) and autonomic nervous system
(ANS). The SNS carries sensory information from sensory organs to the CNS;
controls voluntary body movements. The ANS regulates involuntary and
unconscious actions. The ANS has two parts: sympathetic NS – activates the
‘fight or flight' response; and parasympathetic NS – calms and helps the body
to conserve energy.
QUESTION:
The
Difference between Simple Reflex and Conditioned Reflex Action
ANSWERS: Differences:
simple reflex action/conditioned reflex action respectively: it requires only
one stimulus/it involves more than one stimuli; it mostly involves the spinal
cord/involves the brain; it is an immediate action (no time to learn)/it
requires time to learn; it is inborn behaviour/it is an acquired behaviour
(learned behaviour); action starts by muscle receptor cells/it starts in the
brain
QUESTION:
The
Classes of the Division Angiospermophyta and their Distinctive Features
ANSWERS: Distinctive
features of class monocotyledonae: they have one seed leaf, leaf veins
parallel, flower parts in threes or multiple of threes, vascular bundles
scattered, no secondary growth, fibrous root system. Class dicotyledonae: have
two seed leaves, leaf veins reticulated, flower parts in fours or fives or
multiples thereof, vascular bundles arranged in a ring, secondary growth, tap
root system.
QUESTION:
Experiments
to Investigate Movement in Plants
ANSWERS: Phototropism
(cover a potted plant with a box and cut a small hole in the side of the box).
Geotropism (uproot a health plant and lay it flat on soil for 5 days and keep
irrigating the soil). Hydrotropisms (plant a seed some distance away from water
source and observe the direction of root growth). Thigmotropism (fix a stick
close to bean plant). Seismonasty (touch leaves mimosa pudica).
QUESTION:
The
Concept of Coordination in Organisms
ANSWERS: All
living organisms respond and react to changes in the environment around them.
These changes are called stimuli (singular: stimulus). Examples of stimuli are
light, heat, coldness, sound, smell, taste, touch, pressure, pain, water, and
force of gravity, etc. The ability to perceive, interpret and respond to
stimuli is called irritability or sensitivity.
QUESTION:
General
and Distinctive Features of the Division Coniferophyta
ANSWERS: General
characteristics of Division Coniferophyta: vascular; mostly evergreen trees and
shrubs; xeromorphic; have secondary growth; reproduce sexually by seeds;
world's tallest plants (1-100m); have alteration of generation; Distinctive
features: their seeds are not enclosed in ovary, but in cones; have needle-like
leaves with a thick cuticle; and they are non-flowering but seed bearing
plants.
QUESTION:
Adaptations
of Different Types of Muscles to their Roles
ANSWERS: Some
adaptations of muscles are: (1) Cardiac muscles (have numerous mitochondria
that supply energy; they are elastic, branched, striated, multinucleated, and
have intercalated discs. (2) Smooth muscles (connected to autonomic nervous
system; have many mitochondria and elastic myofibrils). (3) Skeletal muscles
(they are multinucleated, have long cells and are striated).
QUESTION:
Disorders
of Hormonal Coordination in Mammals
ANSWERS: Some
endocrine diseases and disorders of named glands include: pituitary gland
(gigantism, dwarfism); thyroid gland (Grave's disease, cretinism, goitre,
thyroid cancer); parathyroid gland (osteoporosis); adrenal gland (Addison’s
disease, adrenal cancer, Cushing’s syndrome); pancreas (diabetes,
hyperglycemia, hypoglycaemia); ovaries (ovarian cancer, ovarian cysts); and
testes (hypogonadism).
QUESTION:
Types
of Movement Exhibited by Plants
ANSWERS: Tropic
movements are movements of curvature that respond to the direction of the
external stimulus. Important tropisms include phototropism, geotropism,
hydrotropism, chemotropism and thigmotropism. Nastic movements are plant
movements independent of the direction of the external stimulus. Nastic
movements include epinasty, hyponasty, hydronasty, nyctinasty, seismonasty, and
thigmonasty.
QUESTION:
The
Functions of the Major Components of the Human Skeleton and their Adaptations
ANSWERS: The
functions of skeleton are: (a) support (point for muscle attachment); (b) protection
(skull protects brain, vertebrae protect the spinal cord, and the ribcage and
breast bone protect the heart and lungs); (c) locomotion (skeleton as a lever
system allows movement); (d) storage of minerals (Ca & P); (e) blood
formation (red bone marrow produces red blood cells and phagocytes); (f)
feeding.
QUESTION:
How
Muscles Facilitate Movement
ANSWERS: You
will need to learn about the muscles of the body in order to understand how
this system contributes to the overall design of the human body. The human body
is composed of over 500 muscles working together to facilitate movement.
Movement occurs when muscles contract or shorten, pulling the bones with them.
Muscles work in pairs; when one shortens, the corresponding muscle lengthens.
QUESTION:
The
Concept of Movement in Plants (Movement of Curvature)
ANSWERS: Generally,
plants do not show locomotion (movement of the entire organism). However,
movement of individual plant organs is possible, modified by sensitivity of the
plant to external stimuli. Plant organs move toward scarce resource or
otherwise secure food, or use movement as an adaptation to escape or minimize
injury from harmful external factors, or ensure development.
QUESTION:
Movement
and Locomotion Actions
ANSWERS: The
most visible activities that consume the stored energy in organisms are the
movements and locomotion. These activities keep the organisms or parts of them
in motion. Examples of locomotion actions include walking, running, leaping,
hopping, jumping, gliding, flying, or swimming using legs, wings, or fins.
Movement actions include bending, squatting, shaking, kicking, speaking, or
writing.
QUESTION:
The
Structure of Representative Plants Under Each Class (Monocotyledonae and
Dicotyledonae)
ANSWERS: Plants
belonging to monocotyledonae and dicotyledonae can easily be distinguished from
one another by their observable features. Such features include number of
cotyledons, pollen structure, leaf veins, stem vascular arrangement, root
development and structure, and whether a plant has or not secondary growth.
QUESTION:
The
Ways in Which Coordination is Brought About
ANSWERS: Coordination
in both plants and animals is brought by hormones. Plants produce hormones,
such as auxins, and respond to external stimuli e.g., light, touch,
temperature, etc. In animals, the nervous system and sense organs also take
part in coordination. The nervous system of an animal coordinates many
activities in the body. Sense organs are sensitive to external stimuli such as
sound and touch.
QUESTION:
The
Structure of Muscles
ANSWERS: Skeletal,
cardiac, and smooth muscle tissues are made of specialised cells. Skeletal
muscle tissue cells are voluntary, striated, not branched, and multi-nucleated;
cardiac muscle tissue cells are involuntary and intrinsically controlled,
striated, branched, and singly nucleated; and smooth muscle tissue cells are
involuntarily controlled, not striated, not branched, and singly nucleated.
QUESTION:
Advantages
and Disadvantages of Division Angiospermophyta
ANSWERS: Advantages
of angiosperms: Human food; Livestock feed; Wood (for furniture, charcoal,
paper); Textile (textile fibres); Medicine (medicinal herbs); Produce flowers
for sale; Forestry (study); Ecology (animal habitats) Climate modification; and
Ecotourism. Disadvantages: Toxins (some plants are poisonous when eaten by
human and other animals). Drugs (misused as drugs); Weeds (some are bad weeds).
QUESTION:
The
Structure of Pinus
ANSWERS: Pines
are species of trees in the genus Pinus. Barks of most pines are thick and
scaly. The branches are produced in regular whorls. A cross-section of pine
stem has several concentric rings with distinct borders between each ring. They
have needle-like leaves. The leaves are in bundles or clusters. They also have
non-photosynthetic scale leaves. A cone contains the reproductive structures.
QUESTION:
The
Concept of Tropic and Nastic Responses
ANSWERS: Tropisms
are growth responses of plants that result in curvatures of plant organs toward
or away from certain stimuli. Important tropisms in plants include
phototropism, gravitropism, hydrotropism and thigmotropism. Nastic responses
are non-directional responses to the intensity of a stimulus. Nastic responses
include thigmonasty, thermonasty, hydronasty, etiolation, and photonasty.
QUESTION:
The
Difference between Simple Reflex and Conditioned Reflex Action
ANSWERS: Differences:
simple reflex action/conditioned reflex action respectively: it requires only
one stimulus/it involves more than one stimuli; it mostly involves the spinal
cord/involves the brain; it is an immediate action (no time to learn)/it
requires time to learn; it is inborn behaviour/it is an acquired behaviour
(learned behaviour); action starts by muscle receptor cells/it starts in the
brain
QUESTION:
The
Importance of Tropic and Nastic Responses
ANSWERS: Tropic
and nastic responses allow plants to survive, grow, develop and reproduce. That
is, they enable plants to anchor in the soil, absorb water and minerals, and
expose leaves to sunlight for photosynthesis; and also help in plant support,
enable the plant to survive by avoiding contact with harmful chemicals, trap
and digest insects, and facilitate the fertilization process in flowering plants.
QUESTION:
The
Concept of Muscles
ANSWERS: Muscles
are soft tissue found in most animals. Muscle cells contain protein filaments
of actin and myosin that slide past one another, producing a contraction that
changes both length & shape of cell. Muscles are responsible for
maintaining and changing posture, locomotion, and movement of internal organs,
e.g. contraction of the heart and movement of food through digestive system by
peristalsis.
QUESTION:
Causes
and Effects of Drug Addiction
ANSWERS: Some
causes of drug abuse include misuse of medical drugs, peer pressure, and lack
of life and social skills. Effects of drug abuse and addiction include
dependency, mental confusion, heart failure, disruption of normal body
functions, aggressiveness, crime and violence, spread of contagious diseases
through sharing needles, misuse of money on drugs, body deterioration, birth
defect, and death.
QUESTION:
The
Concept of Movement in Plants (Movement of Curvature)
ANSWERS: Generally,
plants do not show locomotion (movement of the entire organism). However,
movement of individual plant organs is possible, modified by sensitivity of the
plant to external stimuli. Plant organs move toward scarce resource or
otherwise secure food, or use movement as an adaptation to escape or minimize
injury from harmful external factors, or ensure development.
QUESTION:
Causes
Effects and Preventive Measures of Muscles Cramps
ANSWERS: Causes
of muscle pain: muscle injury, dehydration, low Ca, K, Na, and Mg, and low
blood supply. Also spinal nerve compression, alcoholism, pregnancy, kidney
failure, hypothyroidism, or low thyroid gland function can cause muscle cramps.
Effects: muscle pain, may interrupt sleep, or make it difficult to walk.
Prevention: Ca, K and fluid intake, and stretching or warming up before
exercise.
QUESTION:
The
Components of the Peripheral Nervous System and Their Functions
ANSWERS: PNS
has two components: somatic nervous system (SNS) and autonomic nervous system
(ANS). The SNS carries sensory information from sensory organs to the CNS;
controls voluntary body movements. The ANS regulates involuntary and
unconscious actions. The ANS has two parts: sympathetic NS – activates the
‘fight or flight' response; and parasympathetic NS – calms and helps the body
to conserve energy.
QUESTION:
Causes
and Effects of Drug Addiction
ANSWERS: Some
causes of drug abuse include misuse of medical drugs, peer pressure, and lack
of life and social skills. Effects of drug abuse and addiction include
dependency, mental confusion, heart failure, disruption of normal body
functions, aggressiveness, crime and violence, spread of contagious diseases
through sharing needles, misuse of money on drugs, body deterioration, birth
defect, and death.
QUESTION:
Adaptations
of Different Types of Muscles to their Roles
ANSWERS: Some
adaptations of muscles are: (1) Cardiac muscles (have numerous mitochondria
that supply energy; they are elastic, branched, striated, multinucleated, and
have intercalated discs. (2) Smooth muscles (connected to autonomic nervous
system; have many mitochondria and elastic myofibrils). (3) Skeletal muscles
(they are multinucleated, have long cells and are striated).
QUESTION:
The
Components of the Central Nervous System and their Functions
ANSWERS: Some
parts and (functions) of the brain are: Cerebellum (concerned with long-term
memory, co-ordination, etc); Cerebrum (controls emotions, hearing, vision,
personality, etc); Medulla oblongata (controls involuntary activities such as
breathing, heartbeat, etc); Spinal cord (transmission of neural signals between
the brain and the rest of the body, controls numerous reflexes).
QUESTION:
Advantages
and Disadvantages of Division Angiospermophyta
ANSWERS: Advantages
of angiosperms: Human food; Livestock feed; Wood (for furniture, charcoal,
paper); Textile (textile fibres); Medicine (medicinal herbs); Produce flowers
for sale; Forestry (study); Ecology (animal habitats) Climate modification; and
Ecotourism. Disadvantages: Toxins (some plants are poisonous when eaten by
human and other animals). Drugs (misused as drugs); Weeds (some are bad weeds).
QUESTION:
The
Functions of the Major Components of the Human Skeleton and their Adaptations
ANSWERS: The
functions of skeleton are: (a) support (point for muscle attachment); (b)
protection (skull protects brain, vertebrae protect the spinal cord, and the
ribcage and breast bone protect the heart and lungs); (c) locomotion (skeleton
as a lever system allows movement); (d) storage of minerals (Ca & P); (e)
blood formation (red bone marrow produces red blood cells and phagocytes); (f)
feeding.
QUESTION:
Types
of Movement Exhibited by Plants
ANSWERS: Tropic
movements are movements of curvature that respond to the direction of the
external stimulus. Important tropisms include phototropism, geotropism,
hydrotropism, chemotropism and thigmotropism. Nastic movements are plant
movements independent of the direction of the external stimulus. Nastic
movements include epinasty, hyponasty, hydronasty, nyctinasty, seismonasty, and
thigmonasty.
QUESTION:
General
and Distinctive Features of the Division Coniferophyta
ANSWERS: General
characteristics of Division Coniferophyta: vascular; mostly evergreen trees and
shrubs; xeromorphic; have secondary growth; reproduce sexually by seeds;
world's tallest plants (1-100m); have alteration of generation; Distinctive
features: their seeds are not enclosed in ovary, but in cones; have needle-like
leaves with a thick cuticle; and they are non-flowering but seed bearing
plants.
QUESTION:
The
Concept of Tropic and Nastic Responses
ANSWERS: Tropisms
are growth responses of plants that result in curvatures of plant organs toward
or away from certain stimuli. Important tropisms in plants include
phototropism, gravitropism, hydrotropism and thigmotropism. Nastic responses
are non-directional responses to the intensity of a stimulus. Nastic responses
include thigmonasty, thermonasty, hydronasty, etiolation, and photonasty.
QUESTION:
Proper
Ways of Handling and Using Drugs
ANSWERS: Proper
use and handling of drugs include: avoiding taking any drug without
prescription by the doctor, staying away from peer pressures and drug addicts,
keeping oneself busy with an activity, reporting any drug abuse or trafficking,
youth counselling, rehabilitation of addicts, avoiding overdose of
over-the-counter drugs, finishing the prescribed doses, and keeping drugs out
of children’s reach.
QUESTION:
General
and Distinctive Features of the Division Angiospermophyta
ANSWERS: General
characteristics of division angiospermophyta: they are flowering plants; bear
seeds; have root and shoot systems; and show alternation of generation.
Distinctive features: they have reproductive structures (flowers), endosperm,
double fertilization, and vascular system; they bear seeds enclosed in a fruit,
and their haploid gametophyte is confined inside the ovary or anther of the
flower.
QUESTION:
The
Concept of Movement and Locomotion
ANSWERS: Locomotion
is the movement of an entire organism from one place to another. The locomotion
of human or other animals is accomplished through walking, running, leaping,
jumping, gliding, flying, or swimming. Movement only involves part of an
organism’s body. Examples of movements include moving a hand, leg, head or any
part of the body. Both movement and locomotion spend energy stored in the body.
QUESTION:
Process
of Fertilization in Flowering Plants
ANSWERS: During
growth of the pollen tube, the generative nucleus, behind the tube nucleus,
divides by mitosis to produce 2 male haploid sperm nuclei. The pollen tube
enters the ovule through the micropyle and penetrates the embryo sac wall.
Then, the tip of the tube bursts open, the tube nucleus disintegrates, creating
a passage for the male nuclei and what follows is called double fertilisation.
QUESTION:
Movement
and Locomotion Actions
ANSWERS: The
most visible activities that consume the stored energy in organisms are the
movements and locomotion. These activities keep the organisms or parts of them
in motion. Examples of locomotion actions include walking, running, leaping,
hopping, jumping, gliding, flying, or swimming using legs, wings, or fins.
Movement actions include bending, squatting, shaking, kicking, speaking, or
writing.
QUESTION:
The
Classes of the Division Angiospermophyta and their Distinctive Features
ANSWERS: Distinctive
features of class monocotyledonae: they have one seed leaf, leaf veins
parallel, flower parts in threes or multiple of threes, vascular bundles
scattered, no secondary growth, fibrous root system. Class dicotyledonae: have
two seed leaves, leaf veins reticulated, flower parts in fours or fives or
multiples thereof, vascular bundles arranged in a ring, secondary growth, tap
root system.
QUESTION:
Causes
and Effects of Drug Addiction
ANSWERS: Some
causes of drug abuse include misuse of medical drugs, peer pressure, and lack
of life and social skills. Effects of drug abuse and addiction include
dependency, mental confusion, heart failure, disruption of normal body
functions, aggressiveness, crime and violence, spread of contagious diseases
through sharing needles, misuse of money on drugs, body deterioration, birth
defect, and death.
QUESTION:
Adaptations
of Different Types of Muscles to their Roles
ANSWERS: Some
adaptations of muscles are: (1) Cardiac muscles (have numerous mitochondria
that supply energy; they are elastic, branched, striated, multinucleated, and
have intercalated discs. (2) Smooth muscles (connected to autonomic nervous
system; have many mitochondria and elastic myofibrils). (3) Skeletal muscles
(they are multinucleated, have long cells and are striated).
QUESTION:
The
Importance of Movement in Animals and Plants
ANSWERS: Movement
and locomotion actions are important to animals and plants because they enable
the animals to (a) escape from danger; (b) move to better climatic conditions;
(c) search for food; and (d) find mate. They also (e) aid in animal or insect
pollination; and (f) enable plant shoots to move towards light and roots
towards water and nutrient sources so as to carry out photosynthesis.
QUESTION:
General
and Distinctive Features of the Division Angiospermophyta
ANSWERS: General
characteristics of division angiospermophyta: they are flowering plants; bear
seeds; have root and shoot systems; and show alternation of generation.
Distinctive features: they have reproductive structures (flowers), endosperm,
double fertilization, and vascular system; they bear seeds enclosed in a fruit,
and their haploid gametophyte is confined inside the ovary or anther of the
flower.
QUESTION:
Proper
Ways of Handling and Using Drugs
ANSWERS: Proper
use and handling of drugs include: avoiding taking any drug without
prescription by the doctor, staying away from peer pressures and drug addicts,
keeping oneself busy with an activity, reporting any drug abuse or trafficking,
youth counselling, rehabilitation of addicts, avoiding overdose of
over-the-counter drugs, finishing the prescribed doses, and keeping drugs out
of children’s reach.
QUESTION:
The
Advantages and Disadvantages of the Division Coniferophyta
ANSWERS: Some
of the advantages of conifers include the following: produce wood that is used
for making timber and furniture and burning charcoal; branches used as
Christmas trees, and cones used for decoration, also pines are cultivated as
ornaments in gardens; produce nuts that are used in human diet; thick
coniferous forests modify climate; and used for biological research and
ecological studies.
QUESTION:
The
Components of the Central Nervous System and their Functions
ANSWERS: Some
parts and (functions) of the brain are: Cerebellum (concerned with long-term
memory, co-ordination, etc); Cerebrum (controls emotions, hearing, vision,
personality, etc); Medulla oblongata (controls involuntary activities such as
breathing, heartbeat, etc); Spinal cord (transmission of neural signals between
the brain and the rest of the body, controls numerous reflexes).
QUESTION:
Types
of Movement Exhibited by Plants
ANSWERS: Tropic
movements are movements of curvature that respond to the direction of the
external stimulus. Important tropisms include phototropism, geotropism,
hydrotropism, chemotropism and thigmotropism. Nastic movements are plant
movements independent of the direction of the external stimulus. Nastic
movements include epinasty, hyponasty, hydronasty, nyctinasty, seismonasty, and
thigmonasty.
QUESTION:
The
Concept of Coordination in Organisms
ANSWERS: All
living organisms respond and react to changes in the environment around them.
These changes are called stimuli (singular: stimulus). Examples of stimuli are
light, heat, coldness, sound, smell, taste, touch, pressure, pain, water, and
force of gravity, etc. The ability to perceive, interpret and respond to
stimuli is called irritability or sensitivity.
QUESTION:
The
Concept of Movement and Locomotion
ANSWERS: Locomotion
is the movement of an entire organism from one place to another. The locomotion
of human or other animals is accomplished through walking, running, leaping,
jumping, gliding, flying, or swimming. Movement only involves part of an
organism’s body. Examples of movements include moving a hand, leg, head or any
part of the body. Both movement and locomotion spend energy stored in the body.
QUESTION:
Types
of Sense Organs and Their Relative Position
ANSWERS: Sense
organs are organs of the body that detect and respond to changes in the
environment (stimuli): eyes; nose; ears [OUTER (pinna & auditory canal),
MIDDLE (eardrum, malleus, incus, & stapes), INNER (cochlea, semicircular
canals & eustachian tube)]; tongue (covered with moist, pink tissue called
mucosa and tiny bumps called papillae); and skin (made of 3 layers - dermis,
epidermis & hypodermis).
QUESTION:
The
Difference between Simple Reflex and Conditioned Reflex Action
ANSWERS: Differences:
simple reflex action/conditioned reflex action respectively: it requires only
one stimulus/it involves more than one stimuli; it mostly involves the spinal
cord/involves the brain; it is an immediate action (no time to learn)/it
requires time to learn; it is inborn behaviour/it is an acquired behaviour
(learned behaviour); action starts by muscle receptor cells/it starts in the brain
QUESTION:
The
Concept of Tropic and Nastic Responses
ANSWERS: Tropisms
are growth responses of plants that result in curvatures of plant organs toward
or away from certain stimuli. Important tropisms in plants include
phototropism, gravitropism, hydrotropism and thigmotropism. Nastic responses
are non-directional responses to the intensity of a stimulus. Nastic responses
include thigmonasty, thermonasty, hydronasty, etiolation, and photonasty.
QUESTION:
The
Concept of Muscles
ANSWERS: Muscles
are soft tissue found in most animals. Muscle cells contain protein filaments
of actin and myosin that slide past one another, producing a contraction that
changes both length & shape of cell. Muscles are responsible for
maintaining and changing posture, locomotion, and movement of internal organs,
e.g. contraction of the heart and movement of food through digestive system by
peristalsis.
QUESTION:
The
Components of the Peripheral Nervous System and Their Functions
ANSWERS: PNS
has two components: somatic nervous system (SNS) and autonomic nervous system
(ANS). The SNS carries sensory information from sensory organs to the CNS;
controls voluntary body movements. The ANS regulates involuntary and
unconscious actions. The ANS has two parts: sympathetic NS – activates the
‘fight or flight' response; and parasympathetic NS – calms and helps the body
to conserve energy.
QUESTION:
Movement
and Locomotion Actions
ANSWERS: The
most visible activities that consume the stored energy in organisms are the
movements and locomotion. These activities keep the organisms or parts of them
in motion. Examples of locomotion actions include walking, running, leaping,
hopping, jumping, gliding, flying, or swimming using legs, wings, or fins.
Movement actions include bending, squatting, shaking, kicking, speaking, or
writing.
QUESTION:
Advantages
and Disadvantages of Division Angiospermophyta
ANSWERS: Advantages
of angiosperms: Human food; Livestock feed; Wood (for furniture, charcoal,
paper); Textile (textile fibres); Medicine (medicinal herbs); Produce flowers
for sale; Forestry (study); Ecology (animal habitats) Climate modification; and
Ecotourism. Disadvantages: Toxins (some plants are poisonous when eaten by
human and other animals). Drugs (misused as drugs); Weeds (some are bad weeds).
QUESTION:
The
Components of the Central Nervous System and their Functions
ANSWERS: Some
parts and (functions) of the brain are: Cerebellum (concerned with long-term
memory, co-ordination, etc); Cerebrum (controls emotions, hearing, vision,
personality, etc); Medulla oblongata (controls involuntary activities such as
breathing, heartbeat, etc); Spinal cord (transmission of neural signals between
the brain and the rest of the body, controls numerous reflexes).
QUESTION:
The
Structure of Muscles
ANSWERS: Skeletal,
cardiac, and smooth muscle tissues are made of specialised cells. Skeletal
muscle tissue cells are voluntary, striated, not branched, and multi-nucleated;
cardiac muscle tissue cells are involuntary and intrinsically controlled,
striated, branched, and singly nucleated; and smooth muscle tissue cells are
involuntarily controlled, not striated, not branched, and singly nucleated.
QUESTION:
Types
of Muscles
ANSWERS: There
are 3 types of muscles: (1) Cardiac muscle – involuntary, striated muscle that
forms the walls of the heart, specifically the myocardium. (2) Skeletal
(voluntary) muscle – occurs in muscles which are attached to bones by bundles
of collagen fibres known as tendons. (3) Smooth (involuntary/visceral) muscles
located in walls of hollow visceral organs, except the heart.
QUESTION:
Experiments
to Investigate Movement in Plants
ANSWERS: Phototropism
(cover a potted plant with a box and cut a small hole in the side of the box).
Geotropism (uproot a health plant and lay it flat on soil for 5 days and keep
irrigating the soil). Hydrotropisms (plant a seed some distance away from water
source and observe the direction of root growth). Thigmotropism (fix a stick
close to bean plant). Seismonasty (touch leaves mimosa pudica).
QUESTION:
The
Importance of Movement in Animals and Plants
ANSWERS: Movement
and locomotion actions are important to animals and plants because they enable
the animals to (a) escape from danger; (b) move to better climatic conditions;
(c) search for food; and (d) find mate. They also (e) aid in animal or insect
pollination; and (f) enable plant shoots to move towards light and roots
towards water and nutrient sources so as to carry out photosynthesis.
QUESTION:
The
Difference between Simple Reflex and Conditioned Reflex Action
ANSWERS: Differences:
simple reflex action/conditioned reflex action respectively: it requires only
one stimulus/it involves more than one stimuli; it mostly involves the spinal
cord/involves the brain; it is an immediate action (no time to learn)/it
requires time to learn; it is inborn behaviour/it is an acquired behaviour
(learned behaviour); action starts by muscle receptor cells/it starts in the
brain
QUESTION:
The
Advantages and Disadvantages of the Division Coniferophyta
ANSWERS: Some
of the advantages of conifers include the following: produce wood that is used
for making timber and furniture and burning charcoal; branches used as
Christmas trees, and cones used for decoration, also pines are cultivated as
ornaments in gardens; produce nuts that are used in human diet; thick
coniferous forests modify climate; and used for biological research and
ecological studies.
QUESTION:
The
role of Hormones produced by each Endocrine gland
ANSWERS: Roles
of SOME hormones: neurohormones of hypothalamus controls pituitary gland
function; pituitary hormones control functions of other endocrine glands;
thyroid hormones regulate the body’s metabolic rate and heart and digestive
function, muscle control, brain development and bone maintenance; and
parathyroid hormone (PTH) controls release calcium from bone cells into the
bloodstream.
QUESTION:
General
and Distinctive Features of the Division Coniferophyta
ANSWERS: General
characteristics of Division Coniferophyta: vascular; mostly evergreen trees and
shrubs; xeromorphic; have secondary growth; reproduce sexually by seeds;
world's tallest plants (1-100m); have alteration of generation; Distinctive
features: their seeds are not enclosed in ovary, but in cones; have needle-like
leaves with a thick cuticle; and they are non-flowering but seed bearing
plants.
QUESTION:
Movement
and Locomotion Actions
ANSWERS: The
most visible activities that consume the stored energy in organisms are the
movements and locomotion. These activities keep the organisms or parts of them
in motion. Examples of locomotion actions include walking, running, leaping,
hopping, jumping, gliding, flying, or swimming using legs, wings, or fins. Movement
actions include bending, squatting, shaking, kicking, speaking, or writing.
QUESTION:
Causes
Effects and Preventive Measures of Muscles Cramps
ANSWERS: Causes
of muscle pain: muscle injury, dehydration, low Ca, K, Na, and Mg, and low
blood supply. Also spinal nerve compression, alcoholism, pregnancy, kidney
failure, hypothyroidism, or low thyroid gland function can cause muscle cramps.
Effects: muscle pain, may interrupt sleep, or make it difficult to walk.
Prevention: Ca, K and fluid intake, and stretching or warming up before
exercise.
QUESTION:
Proper
Ways of Handling and Using Drugs
ANSWERS: Proper
use and handling of drugs include: avoiding taking any drug without
prescription by the doctor, staying away from peer pressures and drug addicts,
keeping oneself busy with an activity, reporting any drug abuse or trafficking,
youth counselling, rehabilitation of addicts, avoiding overdose of
over-the-counter drugs, finishing the prescribed doses, and keeping drugs out
of children’s reach.
QUESTION:
The
Functions of the Major Components of the Human Skeleton and their Adaptations
ANSWERS: The
functions of skeleton are: (a) support (point for muscle attachment); (b)
protection (skull protects brain, vertebrae protect the spinal cord, and the
ribcage and breast bone protect the heart and lungs); (c) locomotion (skeleton
as a lever system allows movement); (d) storage of minerals (Ca & P); (e)
blood formation (red bone marrow produces red blood cells and phagocytes); (f)
feeding.
QUESTION:
The
Concept of Tropic and Nastic Responses
ANSWERS: Tropisms
are growth responses of plants that result in curvatures of plant organs toward
or away from certain stimuli. Important tropisms in plants include
phototropism, gravitropism, hydrotropism and thigmotropism. Nastic responses
are non-directional responses to the intensity of a stimulus. Nastic responses
include thigmonasty, thermonasty, hydronasty, etiolation, and photonasty.
QUESTION:
Types
of Movement Exhibited by Plants
ANSWERS: Tropic
movements are movements of curvature that respond to the direction of the
external stimulus. Important tropisms include phototropism, geotropism,
hydrotropism, chemotropism and thigmotropism. Nastic movements are plant
movements independent of the direction of the external stimulus. Nastic
movements include epinasty, hyponasty, hydronasty, nyctinasty, seismonasty, and
thigmonasty.
QUESTION:
Process
of Fertilization in Flowering Plants
ANSWERS: During
growth of the pollen tube, the generative nucleus, behind the tube nucleus,
divides by mitosis to produce 2 male haploid sperm nuclei. The pollen tube
enters the ovule through the micropyle and penetrates the embryo sac wall.
Then, the tip of the tube bursts open, the tube nucleus disintegrates, creating
a passage for the male nuclei and what follows is called double fertilisation.
QUESTION:
Preventive
and Control Measures of Drug Abuse
ANSWERS: Some
preventive and control measures of drug abuse include: early detection and
treatment of addicts, motivating addicts to make up for detoxification,
inculcating good manners to youth, community education, enforcing laws and
regulations against control and supply of drugs, educating pupils and students
about effects of drugs, and using rehabilitated drug users as campaigners
against drug abuse.
QUESTION:
The
Concept of Movement and Locomotion
ANSWERS: Locomotion
is the movement of an entire organism from one place to another. The locomotion
of human or other animals is accomplished through walking, running, leaping,
jumping, gliding, flying, or swimming. Movement only involves part of an
organism’s body. Examples of movements include moving a hand, leg, head or any
part of the body. Both movement and locomotion spend energy stored in the body.
QUESTION:
The
Structure of Pinus
ANSWERS: Pines
are species of trees in the genus Pinus. Barks of most pines are thick and
scaly. The branches are produced in regular whorls. A cross-section of pine
stem has several concentric rings with distinct borders between each ring. They
have needle-like leaves. The leaves are in bundles or clusters. They also have
non-photosynthetic scale leaves. A cone contains the reproductive structures.
QUESTION:
General
and Distinctive Features of the Division Angiospermophyta
ANSWERS: General
characteristics of division angiospermophyta: they are flowering plants; bear
seeds; have root and shoot systems; and show alternation of generation.
Distinctive features: they have reproductive structures (flowers), endosperm,
double fertilization, and vascular system; they bear seeds enclosed in a fruit,
and their haploid gametophyte is confined inside the ovary or anther of the
flower.
QUESTION:
The
Concept of Movement in Plants (Movement of Curvature)
ANSWERS: Generally,
plants do not show locomotion (movement of the entire organism). However,
movement of individual plant organs is possible, modified by sensitivity of the
plant to external stimuli. Plant organs move toward scarce resource or
otherwise secure food, or use movement as an adaptation to escape or minimize
injury from harmful external factors, or ensure development.
QUESTION:
The
Functions of Sense Organs and their Adaptive Features
ANSWERS: Some
functions of the named sense organs are: SKIN (protection, sensation,
excretion, storage of fat, synthesis of vitamin D, and body temperature
regulation); EAR (hearing and maintaining balance and posture); EYES (vision);
TONGUE (vital in tasting and chewing food and in speech); and NOSE (smelling and
breathing). Each sense organ has adaptive structures which make it fit for its
function(s).
QUESTION:
Types
of Movement Exhibited by Plants
ANSWERS: Tropic
movements are movements of curvature that respond to the direction of the
external stimulus. Important tropisms include phototropism, geotropism,
hydrotropism, chemotropism and thigmotropism. Nastic movements are plant
movements independent of the direction of the external stimulus. Nastic
movements include epinasty, hyponasty, hydronasty, nyctinasty, seismonasty, and
thigmonasty.
QUESTION:
The
Structure of Muscles
ANSWERS: Skeletal,
cardiac, and smooth muscle tissues are made of specialised cells. Skeletal
muscle tissue cells are voluntary, striated, not branched, and multi-nucleated;
cardiac muscle tissue cells are involuntary and intrinsically controlled,
striated, branched, and singly nucleated; and smooth muscle tissue cells are
involuntarily controlled, not striated, not branched, and singly nucleated.
QUESTION:
Process
of Fertilization in Flowering Plants
ANSWERS: During
growth of the pollen tube, the generative nucleus, behind the tube nucleus,
divides by mitosis to produce 2 male haploid sperm nuclei. The pollen tube
enters the ovule through the micropyle and penetrates the embryo sac wall.
Then, the tip of the tube bursts open, the tube nucleus disintegrates, creating
a passage for the male nuclei and what follows is called double fertilisation.
QUESTION:
Movement
and Locomotion Actions
ANSWERS: The
most visible activities that consume the stored energy in organisms are the
movements and locomotion. These activities keep the organisms or parts of them
in motion. Examples of locomotion actions include walking, running, leaping,
hopping, jumping, gliding, flying, or swimming using legs, wings, or fins.
Movement actions include bending, squatting, shaking, kicking, speaking, or
writing.
QUESTION:
Causes
Effects and Preventive Measures of Muscles Cramps
ANSWERS: Causes
of muscle pain: muscle injury, dehydration, low Ca, K, Na, and Mg, and low
blood supply. Also spinal nerve compression, alcoholism, pregnancy, kidney
failure, hypothyroidism, or low thyroid gland function can cause muscle cramps.
Effects: muscle pain, may interrupt sleep, or make it difficult to walk.
Prevention: Ca, K and fluid intake, and stretching or warming up before
exercise.
QUESTION:
The
Structure of Representative Plants Under Each Class (Monocotyledonae and
Dicotyledonae)
ANSWERS: Plants
belonging to monocotyledonae and dicotyledonae can easily be distinguished from
one another by their observable features. Such features include number of
cotyledons, pollen structure, leaf veins, stem vascular arrangement, root
development and structure, and whether a plant has or not secondary growth.
QUESTION:
Proper
Ways of Handling and Using Drugs
ANSWERS: Proper
use and handling of drugs include: avoiding taking any drug without
prescription by the doctor, staying away from peer pressures and drug addicts,
keeping oneself busy with an activity, reporting any drug abuse or trafficking,
youth counselling, rehabilitation of addicts, avoiding overdose of
over-the-counter drugs, finishing the prescribed doses, and keeping drugs out
of children’s reach.
QUESTION:
The
Concept of Coordination in Organisms
ANSWERS: All
living organisms respond and react to changes in the environment around them.
These changes are called stimuli (singular: stimulus). Examples of stimuli are
light, heat, coldness, sound, smell, taste, touch, pressure, pain, water, and
force of gravity, etc. The ability to perceive, interpret and respond to
stimuli is called irritability or sensitivity.
QUESTION:
Experiments
to Investigate Movement in Plants
ANSWERS: Phototropism
(cover a potted plant with a box and cut a small hole in the side of the box).
Geotropism (uproot a health plant and lay it flat on soil for 5 days and keep
irrigating the soil). Hydrotropisms (plant a seed some distance away from water
source and observe the direction of root growth). Thigmotropism (fix a stick
close to bean plant). Seismonasty (touch leaves mimosa pudica).
QUESTION:
The
Classes of the Division Angiospermophyta and their Distinctive Features
ANSWERS: Distinctive
features of class monocotyledonae: they have one seed leaf, leaf veins
parallel, flower parts in threes or multiple of threes, vascular bundles
scattered, no secondary growth, fibrous root system. Class dicotyledonae: have
two seed leaves, leaf veins reticulated, flower parts in fours or fives or
multiples thereof, vascular bundles arranged in a ring, secondary growth, tap
root system.
QUESTION:
Causes
and Effects of Drug Addiction
ANSWERS: Some
causes of drug abuse include misuse of medical drugs, peer pressure, and lack
of life and social skills. Effects of drug abuse and addiction include
dependency, mental confusion, heart failure, disruption of normal body
functions, aggressiveness, crime and violence, spread of contagious diseases
through sharing needles, misuse of money on drugs, body deterioration, birth
defect, and death.
QUESTION:
The
Functions of Sense Organs and their Adaptive Features
ANSWERS: Some
functions of the named sense organs are: SKIN (protection, sensation,
excretion, storage of fat, synthesis of vitamin D, and body temperature regulation);
EAR (hearing and maintaining balance and posture); EYES (vision); TONGUE (vital
in tasting and chewing food and in speech); and NOSE (smelling and breathing).
Each sense organ has adaptive structures which make it fit for its function(s).
QUESTION:
The
role of Hormones produced by each Endocrine gland
ANSWERS: Roles
of SOME hormones: neurohormones of hypothalamus controls pituitary gland
function; pituitary hormones control functions of other endocrine glands;
thyroid hormones regulate the body’s metabolic rate and heart and digestive
function, muscle control, brain development and bone maintenance; and
parathyroid hormone (PTH) controls release calcium from bone cells into the
bloodstream.
QUESTION:
The
Importance of Tropic and Nastic Responses
ANSWERS: Tropic
and nastic responses allow plants to survive, grow, develop and reproduce. That
is, they enable plants to anchor in the soil, absorb water and minerals, and
expose leaves to sunlight for photosynthesis; and also help in plant support,
enable the plant to survive by avoiding contact with harmful chemicals, trap
and digest insects, and facilitate the fertilization process in flowering
plants.
QUESTION:
General
and Distinctive Features of the Division Coniferophyta
ANSWERS: General
characteristics of Division Coniferophyta: vascular; mostly evergreen trees and
shrubs; xeromorphic; have secondary growth; reproduce sexually by seeds;
world's tallest plants (1-100m); have alteration of generation; Distinctive
features: their seeds are not enclosed in ovary, but in cones; have needle-like
leaves with a thick cuticle; and they are non-flowering but seed bearing
plants.
QUESTION:
Advantages
and Disadvantages of Division Angiospermophyta
ANSWERS: Advantages
of angiosperms: Human food; Livestock feed; Wood (for furniture, charcoal,
paper); Textile (textile fibres); Medicine (medicinal herbs); Produce flowers
for sale; Forestry (study); Ecology (animal habitats) Climate modification; and
Ecotourism. Disadvantages: Toxins (some plants are poisonous when eaten by
human and other animals). Drugs (misused as drugs); Weeds (some are bad weeds).
QUESTION:
The
Structure of Pinus
ANSWERS: Pines
are species of trees in the genus Pinus. Barks of most pines are thick and
scaly. The branches are produced in regular whorls. A cross-section of pine
stem has several concentric rings with distinct borders between each ring. They
have needle-like leaves. The leaves are in bundles or clusters. They also have
non-photosynthetic scale leaves. A cone contains the reproductive structures.
QUESTION:
The
Concept of Muscles
ANSWERS: Muscles
are soft tissue found in most animals. Muscle cells contain protein filaments
of actin and myosin that slide past one another, producing a contraction that
changes both length & shape of cell. Muscles are responsible for
maintaining and changing posture, locomotion, and movement of internal organs,
e.g. contraction of the heart and movement of food through digestive system by
peristalsis.
QUESTION:
Types
of Sense Organs and Their Relative Position
ANSWERS: Sense
organs are organs of the body that detect and respond to changes in the
environment (stimuli): eyes; nose; ears [OUTER (pinna & auditory canal),
MIDDLE (eardrum, malleus, incus, & stapes), INNER (cochlea, semicircular
canals & eustachian tube)]; tongue (covered with moist, pink tissue called
mucosa and tiny bumps called papillae); and skin (made of 3 layers - dermis,
epidermis & hypodermis).
QUESTION:
The
Structures of Human Skeleton
ANSWERS: The
human skeleton is the internal framework of the body. It can be divided into
the axial skeleton and the appendicular skeleton. The axial skeleton is formed
by the vertebral column, the rib cage, the skull and other associated bones.
The appendicular skeleton, which is attached to the axial skeleton, is formed
by the shoulder girdle, the pelvic girdle and the bones of the upper and lower
limbs.
QUESTION:
The
Importance of Movement in Animals and Plants
ANSWERS: Movement
and locomotion actions are important to animals and plants because they enable
the animals to (a) escape from danger; (b) move to better climatic conditions;
(c) search for food; and (d) find mate. They also (e) aid in animal or insect
pollination; and (f) enable plant shoots to move towards light and roots
towards water and nutrient sources so as to carry out photosynthesis.
QUESTION:
The
Concept of Muscles
ANSWERS: Muscles
are soft tissue found in most animals. Muscle cells contain protein filaments
of actin and myosin that slide past one another, producing a contraction that
changes both length & shape of cell. Muscles are responsible for
maintaining and changing posture, locomotion, and movement of internal organs,
e.g. contraction of the heart and movement of food through digestive system by
peristalsis.
QUESTION:
Process
of Fertilization in Flowering Plants
ANSWERS: During
growth of the pollen tube, the generative nucleus, behind the tube nucleus,
divides by mitosis to produce 2 male haploid sperm nuclei. The pollen tube
enters the ovule through the micropyle and penetrates the embryo sac wall.
Then, the tip of the tube bursts open, the tube nucleus disintegrates, creating
a passage for the male nuclei and what follows is called double fertilisation.
QUESTION:
Proper
Ways of Handling and Using Drugs
ANSWERS: Proper
use and handling of drugs include: avoiding taking any drug without
prescription by the doctor, staying away from peer pressures and drug addicts,
keeping oneself busy with an activity, reporting any drug abuse or trafficking,
youth counselling, rehabilitation of addicts, avoiding overdose of
over-the-counter drugs, finishing the prescribed doses, and keeping drugs out
of children’s reach.
QUESTION:
The
Concept of Movement in Plants (Movement of Curvature)
ANSWERS: Generally,
plants do not show locomotion (movement of the entire organism). However,
movement of individual plant organs is possible, modified by sensitivity of the
plant to external stimuli. Plant organs move toward scarce resource or
otherwise secure food, or use movement as an adaptation to escape or minimize
injury from harmful external factors, or ensure development.
t,
root development and structure, and whether a plant has or not secondary
growth.
QUESTION:
ction
ANSWERS: Differences:
simple reflex action/conditioned reflex action respectively: it requires only
one stimulus/it involves more than one stimuli; it mostly involves the spinal
cord/involves the brain; it is an immediate action (no time to learn)/it
requires time to learn; it is inborn behaviour/it is an acquired behaviour
(learned behaviour); action starts by muscle receptor cells/it starts in the
brain
QUESTION:
The
Concept of Coordination in Organisms
ANSWERS: All
living organisms respond and react to changes in the environment around them.
These changes are called stimuli (singular: stimulus). Examples of stimuli are
light, heat, coldness, sound, smell, taste, touch, pressure, pain, water, and
force of gravity, etc. The ability to perceive, interpret and respond to
stimuli is called irritability or sensitivity.
QUESTION:
The
Functions of the Major Components of the Human Skeleton and their Adaptations
ANSWERS: The
functions of skeleton are: (a) support (point for muscle attachment); (b)
protection (skull protects brain, vertebrae protect the spinal cord, and the
ribcage and breast bone protect the heart and lungs); (c) locomotion (skeleton
as a lever system allows movement); (d) storage of minerals (Ca & P); (e)
blood formation (red bone marrow produces red blood cells and phagocytes); (f)
feeding.
QUESTION:
The
Difference between Simple Reflex and Conditioned Reflex Action
ANSWERS: Differences:
simple reflex action/conditioned reflex action respectively: it requires only
one stimulus/it involves more than one stimuli; it mostly involves the spinal
cord/involves the brain; it is an immediate action (no time to learn)/it
requires time to learn; it is inborn behaviour/it is an acquired behaviour
(learned behaviour); action starts by muscle receptor cells/it starts in the
brain
QUESTION:
The
Concept of Movement in Plants (Movement of Curvature)
ANSWERS: Generally,
plants do not show locomotion (movement of the entire organism). However,
movement of individual plant organs is possible, modified by sensitivity of the
plant to external stimuli. Plant organs move toward scarce resource or
otherwise secure food, or use movement as an adaptation to escape or minimize
injury from harmful external factors, or ensure development.
QUESTION:
Proper
Ways of Handling and Using Drugs
ANSWERS: Proper
use and handling of drugs include: avoiding taking any drug without
prescription by the doctor, staying away from peer pressures and drug addicts,
keeping oneself busy with an activity, reporting any drug abuse or trafficking,
youth counselling, rehabilitation of addicts, avoiding overdose of
over-the-counter drugs, finishing the prescribed doses, and keeping drugs out
of children’s reach.
QUESTION:
The
Structures of Human Skeleton
ANSWERS: The
human skeleton is the internal framework of the body. It can be divided into
the axial skeleton and the appendicular skeleton. The axial skeleton is formed
by the vertebral column, the rib cage, the skull and other associated bones. The
appendicular skeleton, which is attached to the axial skeleton, is formed by
the shoulder girdle, the pelvic girdle and the bones of the upper and lower
limbs.
QUESTION:
The
Components of the Peripheral Nervous System and Their Functions
ANSWERS: PNS
has two components: somatic nervous system (SNS) and autonomic nervous system
(ANS). The SNS carries sensory information from sensory organs to the CNS;
controls voluntary body movements. The ANS regulates involuntary and
unconscious actions. The ANS has two parts: sympathetic NS – activates the
‘fight or flight' response; and parasympathetic NS – calms and helps the body
to conserve energy.
QUESTION:
The
Functions of Sense Organs and their Adaptive Features
ANSWERS: Some
functions of the named sense organs are: SKIN (protection, sensation,
excretion, storage of fat, synthesis of vitamin D, and body temperature
regulation); EAR (hearing and maintaining balance and posture); EYES (vision);
TONGUE (vital in tasting and chewing food and in speech); and NOSE (smelling
and breathing). Each sense organ has adaptive structures which make it fit for
its function(s).
QUESTION:
The
Advantages and Disadvantages of the Division Coniferophyta
ANSWERS: Some
of the advantages of conifers include the following: produce wood that is used
for making timber and furniture and burning charcoal; branches used as
Christmas trees, and cones used for decoration, also pines are cultivated as
ornaments in gardens; produce nuts that are used in human diet; thick coniferous
forests modify climate; and used for biological research and ecological
studies.
QUESTION:
Movement
and Locomotion Actions
ANSWERS: The
most visible activities that consume the stored energy in organisms are the
movements and locomotion. These activities keep the organisms or parts of them
in motion. Examples of locomotion actions include walking, running, leaping,
hopping, jumping, gliding, flying, or swimming using legs, wings, or fins.
Movement actions include bending, squatting, shaking, kicking, speaking, or
writing.
QUESTION:
The
Concept of Tropic and Nastic Responses
ANSWERS: Tropisms
are growth responses of plants that result in curvatures of plant organs toward
or away from certain stimuli. Important tropisms in plants include
phototropism, gravitropism, hydrotropism and thigmotropism. Nastic responses
are non-directional responses to the intensity of a stimulus. Nastic responses
include thigmonasty, thermonasty, hydronasty, etiolation, and photonasty.
QUESTION:
The
Concept of Coordination in Organisms
ANSWERS: All
living organisms respond and react to changes in the environment around them.
These changes are called stimuli (singular: stimulus). Examples of stimuli are
light, heat, coldness, sound, smell, taste, touch, pressure, pain, water, and
force of gravity, etc. The ability to perceive, interpret and respond to
stimuli is called irritability or sensitivity.
QUESTION:
The
Ways in Which Coordination is Brought About
ANSWERS: Coordination
in both plants and animals is brought by hormones. Plants produce hormones,
such as auxins, and respond to external stimuli e.g., light, touch,
temperature, etc. In animals, the nervous system and sense organs also take
part in coordination. The nervous system of an animal coordinates many
activities in the body. Sense organs are sensitive to external stimuli such as
sound and touch.
QUESTION:
The
Importance of Tropic and Nastic Responses
ANSWERS: Tropic
and nastic responses allow plants to survive, grow, develop and reproduce. That
is, they enable plants to anchor in the soil, absorb water and minerals, and
expose leaves to sunlight for photosynthesis; and also help in plant support,
enable the plant to survive by avoiding contact with harmful chemicals, trap
and digest insects, and facilitate the fertilization process in flowering
plants.
QUESTION:
The
Classes of the Division Angiospermophyta and their Distinctive Features
ANSWERS: Distinctive
features of class monocotyledonae: they have one seed leaf, leaf veins
parallel, flower parts in threes or multiple of threes, vascular bundles
scattered, no secondary growth, fibrous root system. Class dicotyledonae: have
two seed leaves, leaf veins reticulated, flower parts in fours or fives or
multiples thereof, vascular bundles arranged in a ring, secondary growth, tap
root system.
QUESTION:
Causes
Effects and Preventive Measures of Muscles Cramps
ANSWERS: Causes
of muscle pain: muscle injury, dehydration, low Ca, K, Na, and Mg, and low
blood supply. Also spinal nerve compression, alcoholism, pregnancy, kidney
failure, hypothyroidism, or low thyroid gland function can cause muscle cramps.
Effects: muscle pain, may interrupt sleep, or make it difficult to walk.
Prevention: Ca, K and fluid intake, and stretching or warming up before
exercise.
QUESTION:
Preventive
and Control Measures of Drug Abuse
ANSWERS: Some
preventive and control measures of drug abuse include: early detection and
treatment of addicts, motivating addicts to make up for detoxification, inculcating
good manners to youth, community education, enforcing laws and regulations
against control and supply of drugs, educating pupils and students about
effects of drugs, and using rehabilitated drug users as campaigners against
drug abuse.
QUESTION:
The
role of Hormones produced by each Endocrine gland
ANSWERS: Roles
of SOME hormones: neurohormones of hypothalamus controls pituitary gland
function; pituitary hormones control functions of other endocrine glands;
thyroid hormones regulate the body’s metabolic rate and heart and digestive
function, muscle control, brain development and bone maintenance; and
parathyroid hormone (PTH) controls release calcium from bone cells into the
bloodstream.
QUESTION:
How
Muscles Facilitate Movement
ANSWERS: You
will need to learn about the muscles of the body in order to understand how
this system contributes to the overall design of the human body. The human body
is composed of over 500 muscles working together to facilitate movement.
Movement occurs when muscles contract or shorten, pulling the bones with them.
Muscles work in pairs; when one shortens, the corresponding muscle lengthens.
QUESTION:
The
Concept of Movement and Locomotion
ANSWERS: Locomotion
is the movement of an entire organism from one place to another. The locomotion
of human or other animals is accomplished through walking, running, leaping,
jumping, gliding, flying, or swimming. Movement only involves part of an
organism’s body. Examples of movements include moving a hand, leg, head or any
part of the body. Both movement and locomotion spend energy stored in the body.
QUESTION:
The
Structure of Muscles
ANSWERS: Skeletal,
cardiac, and smooth muscle tissues are made of specialised cells. Skeletal
muscle tissue cells are voluntary, striated, not branched, and multi-nucleated;
cardiac muscle tissue cells are involuntary and intrinsically controlled,
striated, branched, and singly nucleated; and smooth muscle tissue cells are
involuntarily controlled, not striated, not branched, and singly nucleated.
QUESTION:
Preventive
and Control Measures of Drug Abuse
ANSWERS: Some
preventive and control measures of drug abuse include: early detection and
treatment of addicts, motivating addicts to make up for detoxification,
inculcating good manners to youth, community education, enforcing laws and
regulations against control and supply of drugs, educating pupils and students
about effects of drugs, and using rehabilitated drug users as campaigners
against drug abuse.
QUESTION:
Proper
Ways of Handling and Using Drugs
ANSWERS: Proper
use and handling of drugs include: avoiding taking any drug without
prescription by the doctor, staying away from peer pressures and drug addicts,
keeping oneself busy with an activity, reporting any drug abuse or trafficking,
youth counselling, rehabilitation of addicts, avoiding overdose of
over-the-counter drugs, finishing the prescribed doses, and keeping drugs out
of children’s reach.
QUESTION:
Adaptations
of Different Types of Muscles to their Roles
ANSWERS: Some
adaptations of muscles are: (1) Cardiac muscles (have numerous mitochondria
that supply energy; they are elastic, branched, striated, multinucleated, and
have intercalated discs. (2) Smooth muscles (connected to autonomic nervous
system; have many mitochondria and elastic myofibrils). (3) Skeletal muscles
(they are multinucleated, have long cells and are striated).
QUESTION:
How
Muscles Facilitate Movement
ANSWERS: You
will need to learn about the muscles of the body in order to understand how
this system contributes to the overall design of the human body. The human body
is composed of over 500 muscles working together to facilitate movement.
Movement occurs when muscles contract or shorten, pulling the bones with them. Muscles
work in pairs; when one shortens, the corresponding muscle lengthens.
QUESTION:
Causes
Effects and Preventive Measures of Muscles Cramps
ANSWERS: Causes
of muscle pain: muscle injury, dehydration, low Ca, K, Na, and Mg, and low
blood supply. Also spinal nerve compression, alcoholism, pregnancy, kidney
failure, hypothyroidism, or low thyroid gland function can cause muscle cramps.
Effects: muscle pain, may interrupt sleep, or make it difficult to walk.
Prevention: Ca, K and fluid intake, and stretching or warming up before
exercise.
QUESTION:
Advantages
and Disadvantages of Division Angiospermophyta
ANSWERS: Advantages
of angiosperms: Human food; Livestock feed; Wood (for furniture, charcoal,
paper); Textile (textile fibres); Medicine (medicinal herbs); Produce flowers
for sale; Forestry (study); Ecology (animal habitats) Climate modification; and
Ecotourism. Disadvantages: Toxins (some plants are poisonous when eaten by
human and other animals). Drugs (misused as drugs); Weeds (some are bad weeds).
QUESTION:
Causes
and Effects of Drug Addiction
ANSWERS: Some
causes of drug abuse include misuse of medical drugs, peer pressure, and lack
of life and social skills. Effects of drug abuse and addiction include
dependency, mental confusion, heart failure, disruption of normal body
functions, aggressiveness, crime and violence, spread of contagious diseases
through sharing needles, misuse of money on drugs, body deterioration, birth
defect, and death.
QUESTION:
The
Classes of the Division Angiospermophyta and their Distinctive Features
ANSWERS: Distinctive
features of class monocotyledonae: they have one seed leaf, leaf veins
parallel, flower parts in threes or multiple of threes, vascular bundles
scattered, no secondary growth, fibrous root system. Class dicotyledonae: have
two seed leaves, leaf veins reticulated, flower parts in fours or fives or
multiples thereof, vascular bundles arranged in a ring, secondary growth, tap
root system.
QUESTION:
The
Importance of Tropic and Nastic Responses
ANSWERS: Tropic
and nastic responses allow plants to survive, grow, develop and reproduce. That
is, they enable plants to anchor in the soil, absorb water and minerals, and
expose leaves to sunlight for photosynthesis; and also help in plant support,
enable the plant to survive by avoiding contact with harmful chemicals, trap
and digest insects, and facilitate the fertilization process in flowering
plants.
QUESTION:
Types
of Muscles
ANSWERS: There
are 3 types of muscles: (1) Cardiac muscle – involuntary, striated muscle that
forms the walls of the heart, specifically the myocardium. (2) Skeletal
(voluntary) muscle – occurs in muscles which are attached to bones by bundles
of collagen fibres known as tendons. (3) Smooth (involuntary/visceral) muscles
located in walls of hollow visceral organs, except the heart.
QUESTION:
The
Functions of Sense Organs and their Adaptive Features
ANSWERS: Some
functions of the named sense organs are: SKIN (protection, sensation,
excretion, storage of fat, synthesis of vitamin D, and body temperature
regulation); EAR (hearing and maintaining balance and posture); EYES (vision);
TONGUE (vital in tasting and chewing food and in speech); and NOSE (smelling
and breathing). Each sense organ has adaptive structures which make it fit for
its function(s).
QUESTION:
The
Difference between Simple Reflex and Conditioned Reflex Action
ANSWERS: Differences:
simple reflex action/conditioned reflex action respectively: it requires only
one stimulus/it involves more than one stimuli; it mostly involves the spinal
cord/involves the brain; it is an immediate action (no time to learn)/it
requires time to learn; it is inborn behaviour/it is an acquired behaviour
(learned behaviour); action starts by muscle receptor cells/it starts in the
brain
QUESTION:
Process
of Fertilization in Flowering Plants
ANSWERS: During
growth of the pollen tube, the generative nucleus, behind the tube nucleus,
divides by mitosis to produce 2 male haploid sperm nuclei. The pollen tube
enters the ovule through the micropyle and penetrates the embryo sac wall.
Then, the tip of the tube bursts open, the tube nucleus disintegrates, creating
a passage for the male nuclei and what follows is called double fertilisation.
QUESTION:
The
Ways in Which Coordination is Brought About
ANSWERS: Coordination
in both plants and animals is brought by hormones. Plants produce hormones,
such as auxins, and respond to external stimuli e.g., light, touch,
temperature, etc. In animals, the nervous system and sense organs also take
part in coordination. The nervous system of an animal coordinates many
activities in the body. Sense organs are sensitive to external stimuli such as
sound and touch.
QUESTION:
The
Structure of Representative Plants Under Each Class (Monocotyledonae and
Dicotyledonae)
ANSWERS: Plants
belonging to monocotyledonae and dicotyledonae can easily be distinguished from
one another by their observable features. Such features include number of
cotyledons, pollen structure, leaf veins, stem vascular arrangement, root
development and structure, and whether a plant has or not secondary growth.
QUESTION:
The
role of Hormones produced by each Endocrine gland
ANSWERS: Roles
of SOME hormones: neurohormones of hypothalamus controls pituitary gland
function; pituitary hormones control functions of other endocrine glands;
thyroid hormones regulate the body’s metabolic rate and heart and digestive
function, muscle control, brain development and bone maintenance; and parathyroid
hormone (PTH) controls release calcium from bone cells into the bloodstream.
QUESTION:
The
Structure of Pinus
ANSWERS: Pines
are species of trees in the genus Pinus. Barks of most pines are thick and
scaly. The branches are produced in regular whorls. A cross-section of pine
stem has several concentric rings with distinct borders between each ring. They
have needle-like leaves. The leaves are in bundles or clusters. They also have
non-photosynthetic scale leaves. A cone contains the reproductive structures.
QUESTION:
Experiments
to Investigate Movement in Plants
ANSWERS: Phototropism
(cover a potted plant with a box and cut a small hole in the side of the box).
Geotropism (uproot a health plant and lay it flat on soil for 5 days and keep irrigating
the soil). Hydrotropisms (plant a seed some distance away from water source and
observe the direction of root growth). Thigmotropism (fix a stick close to bean
plant). Seismonasty (touch leaves mimosa pudica).
QUESTION:
The
Components of the Central Nervous System and their Functions
ANSWERS: Some
parts and (functions) of the brain are: Cerebellum (concerned with long-term
memory, co-ordination, etc); Cerebrum (controls emotions, hearing, vision,
personality, etc); Medulla oblongata (controls involuntary activities such as
breathing, heartbeat, etc); Spinal cord (transmission of neural signals between
the brain and the rest of the body, controls numerous reflexes).
QUESTION:
The
Structures of Human Skeleton
ANSWERS: The
human skeleton is the internal framework of the body. It can be divided into
the axial skeleton and the appendicular skeleton. The axial skeleton is formed
by the vertebral column, the rib cage, the skull and other associated bones.
The appendicular skeleton, which is attached to the axial skeleton, is formed
by the shoulder girdle, the pelvic girdle and the bones of the upper and lower
limbs.
QUESTION:
Movement
and Locomotion Actions
ANSWERS: The
most visible activities that consume the stored energy in organisms are the
movements and locomotion. These activities keep the organisms or parts of them
in motion. Examples of locomotion actions include walking, running, leaping,
hopping, jumping, gliding, flying, or swimming using legs, wings, or fins.
Movement actions include bending, squatting, shaking, kicking, speaking, or
writing.
QUESTION:
The
Components of the Central Nervous System and their Functions
ANSWERS: Some
parts and (functions) of the brain are: Cerebellum (concerned with long-term
memory, co-ordination, etc); Cerebrum (controls emotions, hearing, vision,
personality, etc); Medulla oblongata (controls involuntary activities such as
breathing, heartbeat, etc); Spinal cord (transmission of neural signals between
the brain and the rest of the body, controls numerous reflexes).
QUESTION:
Proper
Ways of Handling and Using Drugs
ANSWERS: Proper
use and handling of drugs include: avoiding taking any drug without
prescription by the doctor, staying away from peer pressures and drug addicts,
keeping oneself busy with an activity, reporting any drug abuse or trafficking,
youth counselling, rehabilitation of addicts, avoiding overdose of
over-the-counter drugs, finishing the prescribed doses, and keeping drugs out
of children’s reach.
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