Coordination and Response
Each subtopic includes About section, revision page link, 10 preview questions, and practice CTAs.
Nervous control in humans
SubtopicNervous control in humans under Coordination and Response for Grade 12 IGCSE.
Preview questions (no answers)
- 1.
In the human nervous system, where is the cytoplasm of a motor neuron located?
A.Only in the axon
B.In the cell body and the axon
C.Only in the synapse
D.Only in the dendrites
- 2.
Which of these is NOT an automatic reflex?
A.Knee-jerk reaction
B.Withdrawing hand from a hot stove
C.Picking up a book to read
D.Sneezing when dust enters the nose
- 3.
Which neuron is usually the first to be activated when you step on a sharp pin?
A.Motor neuron
B.Sensory neuron
C.Relay neuron
D.Brain neuron
- 4.
What ensures that nerve impulses travel in only one direction?
A.The length of the axon
B.The myelin sheath
C.The presence of synapses
D.The speed of the impulse
- 5.
What is the result of the circular muscles of the iris contracting?
A.The pupil becomes larger (dilates)
B.The lens becomes thicker
C.The pupil becomes smaller (constricts)
D.The suspensory ligaments become slack
- 6.
Which part of the nervous system is responsible for involuntary actions such as heart rate and digestion?
A.Somatic nervous system
B.Autonomic nervous system
C.Voluntary nervous system
D.Sensory nervous system
- 7.
Why is the nervous response typically faster than the hormonal response?
A.Nerves use blood to transport signals
B.Nerves use electrical impulses that travel rapidly along axons
C.Hormones must be synthesized after a stimulus occurs
D.Nerves only target one cell at a time
- 8.
Why can humans see in very dim light but with low detail and no color?
A.Cone cells are highly sensitive to low light but lack color pigments.
B.Rod cells are highly sensitive but exhibit high convergence on ganglion cells.
C.The lens cannot focus light properly in the dark.
D.The brain ignores color signals when the heart rate is low.
- 9.
Where are the cell bodies of sensory neurons typically located?
A.In the gray matter of the spinal cord.
B.In the dorsal root ganglia.
C.In the brainstem.
D.In the effectors.
- 10.
What happens to the focal length of the lens when the suspensory ligaments are under high tension?
A.The focal length increases.
B.The focal length decreases.
C.The focal length remains constant.
D.The focal length becomes zero.
Download the worksheet for Coordination and Response - Nervous control in humans to practice offline. It includes additional chapter-level practice questions.
Sense organs (Eye)
SubtopicSense organs (Eye) under Coordination and Response for Grade 12 IGCSE.
Preview questions (no answers)
- 1.
What happens to the image formed on the retina before it is perceived by the brain?
A.It is magnified
B.It is turned upright by the brain
C.It is filtered for color
D.It is mirrored
- 2.
Which structure provides the most nourishment to the cells of the retina?
A.The choroid
B.The vitreous humor
C.The lens
D.The sclera
- 3.
What describes the change in the iris when you enter a dark room?
A.Circular muscles contract, pupil narrows
B.Radial muscles contract, pupil widens
C.Ciliary muscles relax, pupil narrows
D.Suspensory ligaments tighten, pupil widens
- 4.
Which of these structures is not involved in the pathway of light reaching the retina?
A.Cornea
B.Aqueous humor
C.Pupil
D.Optic nerve
- 5.
When the suspensory ligaments are under high tension, the lens is:
A.Relaxed and thick
B.Pulled thin and less refractive
C.Released and more convex
D.Contracted and opaque
- 6.
How do the images produced by the two eyes help in perception?
A.They produce a flat, two-dimensional image
B.They allow for binocular vision and depth perception
C.They ensure that the blind spot of one eye is identical to the other
D.They allow the lens to stay relaxed
- 7.
Which of the following is true about the vitreous humor?
A.It is watery and located in front of the lens
B.It is a jelly-like substance that helps maintain the shape of the eyeball
C.It is responsible for changing the pupil size
D.It is only present during the development of the embryo
- 8.
The 'trichromatic theory' of color vision is based on the existence of three types of cones. Which colors are these cones most sensitive to?
A.Red, Yellow, Blue
B.Red, Green, Blue
C.Yellow, Green, Red
D.Blue, Green, Cyan
- 9.
Which component of the eye contains no blood vessels and relies on the aqueous humor for nutrients?
A.The retina
B.The choroid
C.The cornea
D.The sclera
- 10.
What happens to the ciliary muscles when the eye focuses on an object at 'infinity'?
A.They are in a state of maximum contraction
B.They are in a state of maximum relaxation
C.They rhythmically contract and relax
D.They pull the lens forward towards the cornea
Download the worksheet for Coordination and Response - Sense organs (Eye) to practice offline. It includes additional chapter-level practice questions.
Preview questions (no answers)
- 1.
Which organ filters hormones out of the blood so they can be processed by the liver or excreted?
A.The lungs
B.The heart
C.The kidneys
D.The stomach
- 2.
What is the name of the storage carbohydrate found in the liver that is affected by insulin and glucagon?
A.Glucose
B.Starch
C.Glycogen
D.Cellulose
- 3.
When adrenaline is released, where is blood diverted away from?
A.The heart
B.The skeletal muscles
C.The brain
D.The digestive system
- 4.
Which hormone is primarily involved in the development of female secondary sexual characteristics?
A.Testosterone
B.Insulin
C.Oestrogen
D.Glucagon
- 5.
The diagram shows the hormonal coordination of the menstrual cycle involving the pituitary gland and the ovaries. Which hormones are represented by 'Hormone 1' and 'Hormone 2'?
A.Hormone 1: Luteinizing Hormone (); Hormone 2: Follicle-Stimulating Hormone ()
B.Hormone 1: Follicle-Stimulating Hormone (); Hormone 2: Oestrogen
C.Hormone 1: Oestrogen; Hormone 2: Luteinizing Hormone ()
D.Hormone 1: Progesterone; Hormone 2: Follicle-Stimulating Hormone ()
- 6.
In the regulation of blood sugar, which tissue acts as a glucose reservoir?
A.Brain tissue
B.Lung tissue
C.Liver and muscle tissue
D.Kidney tissue
- 7.
What is the target organ for the hormone ADH?
A.The heart
B.The liver
C.The kidney
D.The bladder
- 8.
Which statement best describes the effect of adrenaline on the metabolic rate of body cells?
A.It decreases the rate of aerobic respiration to conserve oxygen
B.It increases the rate of aerobic respiration to provide more ATP for action
C.It has no effect on respiration, only on heart rate
D.It switches all cells to anaerobic respiration to save time
- 9.
What is the primary effect of insulin on the plasma membrane of muscle cells?
A.It makes the membrane impermeable to all ions
B.It triggers the translocation of glucose transporter proteins to the membrane
C.It causes the membrane to actively pump glucose out of the cell
D.It stimulates the breakdown of the phospholipid bilayer
- 10.
Which phase of the menstrual cycle is characterized by the highest levels of both estrogen and progesterone?
A.Menstrual phase
B.Follicular phase
C.Ovulatory phase
D.Luteal phase
Download the worksheet for Coordination and Response - Hormones to practice offline. It includes additional chapter-level practice questions.
Homeostasis
SubtopicHomeostasis under Coordination and Response for Grade 12 IGCSE.
Preview questions (no answers)
- 1.
Which statement about insulin is correct?
A.It is an enzyme that digests sugar
B.It is a hormone that travels in the blood
C.It is a gas produced by the lungs
D.It is a waste product of the liver
- 2.
What is the effector in the response to high blood glucose?
A.The Pancreas
B.The Brain
C.The Liver
D.The Skin
- 3.
In the liver, glucose is stored as which polymer?
A.Starch
B.Cellulose
C.Glycogen
D.Protein
- 4.
Which of these describes 'negative feedback'?
A.A process that moves a condition further away from the set point
B.A process that reverses a change to return it to the set point
C.A process that has no effect on the body
D.A process only found in the digestive system
- 5.
Which of the following describes the role of receptors in a negative feedback loop?
A.They carry out the response to correct the change
B.They detect the stimulus and send information to the coordination center
C.They determine the set point for the variable
D.They provide the energy needed for the response
- 6.
If a person's body is unable to produce insulin, what is the most likely immediate effect on their blood chemistry after a meal?
A.Blood glucose levels will drop to dangerously low levels
B.Blood glucose levels will remain very high
C.Glycogen stores in the liver will increase rapidly
D.Glucagon levels will rise to compensate
- 7.
In the homeostatic control of blood glucose, what is the role of the blood?
A.It acts as the coordination center
B.It acts as the transport medium for hormones and glucose
C.It acts as the receptor for glucose levels
D.It acts as the effector that stores glycogen
- 8.
If a person's pancreas only produced glucagon and no insulin, what would be the most likely result for their liver's glycogen stores after 24 hours of normal eating?
A.Glycogen stores would be significantly depleted or non-existent
B.Glycogen stores would be excessively high
C.Glycogen stores would remain at a normal level
D.Glycogen would be converted into proteins instead
- 9.
Which statement correctly describes the function of 'vasoconstriction' in cold weather?
A.The capillaries narrow to prevent blood from reaching the skin
B.The skin arterioles narrow, reducing the volume of blood flowing through the capillaries near the skin surface
C.The shunt vessels narrow to force more blood to the skin surface to warm it up
D.The veins in the arms and legs constrict to speed up the return of blood to the heart
- 10.
What is the importance of the high pressure in the glomerulus for homeostasis?
A.It allows for the active transport of urea into the nephron
B.It provides the force for ultrafiltration, allowing waste and water to enter the tubule
C.It prevents the reabsorption of glucose in the proximal tubule
D.It triggers the release of ADH from the hypothalamus
Download the worksheet for Coordination and Response - Homeostasis to practice offline. It includes additional chapter-level practice questions.
Tropic responses (Phototropism/Gravitropism)
SubtopicTropic responses (Phototropism/Gravitropism) under Coordination and Response for Grade 12 IGCSE.
Preview questions (no answers)
- 1.
What happens if you place an opaque cap over the zone of elongation but leave the tip exposed to unilateral light?
A.The shoot grows straight
B.The shoot bends toward the light
C.The shoot dies
D.The shoot grows away from the light
- 2.
Which of these is NOT a characteristic of a tropism?
A.It is a growth response
B.It is permanent
C.It is a rapid, reversible movement
D.It is directed by a stimulus
- 3.
In the gravitropic response of a shoot, which side of the horizontal stem has the fastest growth rate?
A.The lower side
B.The upper side
C.The tip
D.The base
- 4.
What is the resulting growth direction when a seedling is placed in a box with a hole on one side?
A.Straight up
B.Toward the hole
C.Away from the hole
D.Downward
- 5.
A plant is placed in a box with a small hole on one side. After several days, the plant has grown towards the hole. This is an example of:
A.Hydrotropism
B.Negative phototropism
C.Positive phototropism
D.Positive gravitropism
- 6.
Which scientist is often associated with the early experiments demonstrating that a chemical signal moves down from the coleoptile tip?
A.Charles Darwin
B.Gregor Mendel
C.Frits Went
D.Robert Hooke
- 7.
If you remove the root cap from a primary root, how will it respond to gravity?
A.It will grow even faster downwards.
B.It will lose its ability to grow downwards in response to gravity.
C.It will start growing upwards instead.
D.It will immediately branch into lateral roots.
- 8.
If you treat a plant with a drug that disrupts the cytoskeleton (microtubules and actin filaments), how is the gravitropic response affected?
A.It is enhanced because the statoliths can move more freely.
B.It is inhibited because the cytoskeleton is involved in both statolith positioning and PIN protein recycling.
C.It is unaffected because tropisms are purely based on chemical diffusion.
D.The plant will only respond to light, not gravity.
- 9.
What is the primary role of the protein 'TIR1' in the auxin signaling pathway?
A.It is a blue-light photoreceptor.
B.It is a component of an E3 ubiquitin ligase complex that targets repressors for degradation.
C.It is a channel that allows to enter the cell.
D.It is an enzyme that synthesizes IAA from tryptophan.
- 10.
A researcher applies a paste containing a high concentration of auxin to one side of a vertical, healthy stem in the dark. What is the observed result?
A.The stem remains straight.
B.The stem bends toward the side where the paste was applied.
C.The stem bends away from the side where the paste was applied.
D.The stem stops growing entirely.
Download the worksheet for Coordination and Response - Tropic responses (Phototropism/Gravitropism) to practice offline. It includes additional chapter-level practice questions.