chapter 16 question

New Biology – a modern approach 3Chapter 16: Coordination in humans

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Structured Questions

Core Section

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Complete the following paragraph with suitable words selected from below:

black matter brain cerebrum spinal nerves grey matter white matter

cranial nerves spinal cord sensory neurones motor neurones meninges cerebrospinal fluid

The human central nervous system includes two parts. The first part is the (i)_______________ which

is enclosed within the skull in the head. The outer layers of this part are made up of the (ii)_______________

and the inner layer (iii)_______________. The second part is called the (iv)_______________ which runs

down the middle of the backbone. Its internal structure is just opposite to the first part. These two parts are

connected to the skin and muscles by the peripheral nervous system which consists of 12 pairs of

(v)_______________ and 31 pairs of (vi)_______________.

(3 marks)

##

(i) brain (1/2 mark)

(ii) grey matter (1/2 mark)

(iii) white matter (1/2 mark)

(iv) spinal cord (1/2 mark)

(v) cranial nerves (1/2 mark)

(vi) spinal nerves (1/2 mark)

_________

(3 marks)##

________________________________________________________________________________________© Aristo Educational Press Ltd 2007 23


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Read the passage below and answer the questions that follow:

EXAMINING THE NERVOUS SYSTEM

Investigation of nervous disorders involves looking for general symptoms as well as

testing motor and sensory function, sensation, coordination, the eyes, and blood pressure. Here

are three types of investigation: lumbar puncture, EEG and X-rays.

In lumbar puncture, a sample of the cerebrospinal fluid is withdrawn through a needle

inserted between the vertebrae at the back. By examining the constituents of the fluid, much

can be learnt about the state of the nervous system.

The EEG is a machine that records the electrical currents produced by the brain cells.

X-rays applied to the head can often show abnormalities of the skull or its contents. A

radio-opaque liquid is injected into the arteries supplying blood to the brain to show up certain

structures.

(i) State the part of the spinal cord which contains cerebrospinal fluid. (1 mark)

_______________________________________________________________________________

(ii) Give TWO functions of cerebrospinal fluid. (2 marks)

_______________________________________________________________________________

_______________________________________________________________________________

(iii) Explain why the surfaces of the cerebral hemisphere are made up of convolutions. (2 marks)

_______________________________________________________________________________

_______________________________________________________________________________

(iv) Name the part of the brain which gives the sensation of pain after lumbar puncture. (1 mark)

_______________________________________________________________________________

(v) State what would happen to a man if the arteries supplying blood to the motor area of his left

cerebrum are blocked. (3 marks)

_______________________________________________________________________________

_______________________________________________________________________________

##

(i) central canal (1 mark)

(ii) It acts as a shock absorber for protection. (1 mark)

It is a source of nutrients for the brain cells. (1 mark)

(iii) To increase the surface area for (1 mark)

accommodating more neurones to achieve efficient coordination. (1 mark)

(iv) cerebrum (1 mark)

(v) He still has sensation. (1 mark)

But no responses would be produced on the right side of his body. (2 marks)



________________________________________________________________________________________

_________

(9 marks)##

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* Cathy was asked to sit with her legs crossed and the left leg hanging loosely. Angela, her classmate, tapped

her left knee gently.

(i) Describe the response shown by Cathy. (1 mark)

_______________________________________________________________________________

(ii) Name the receptor. (1 mark)

_______________________________________________________________________________

(iii) State the type of the muscle in the leg which is the effector. (1 mark)

_______________________________________________________________________________



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(iv) (1) Complete and label the diagram below to show the pathway of the nerve impulse. Insert two arrows

in appropriate position to show the direction of the transmission. (4 marks)

(2) (a) Add a label in the diagram to show where the dorsal side is. (1 mark)

(b) State the part, visible in the diagram, that supports your decision. (1 mark)

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##

(i) Cathy kicks up her leg. (1 mark)

(ii) stretch receptor (1 mark)

(iii) extensor (1 mark)

(iv) (1)

Drawing includes a sensory neurone (1 mark)



________________________________________________________________________________________

with an arrow pointing towards the centre (1 mark)

and a motor neurone (1 mark)

with an arrow pointing towards the effector. (1 mark)

The neurone must be in the right position. Otherwise no mark is given.

(2) (a) Refer to above diagram. (1 mark)

(b) There is dorsal root ganglion. (1 mark)

_________

(9 marks)##

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Wilson examined a model of a human brain:

(i) State the parts of the brain model, using the letters from the photograph, involved in:

(1) blinking as small particles move towards his eyes; (1 mark)

_______________________________________________________________________________

(2) touching the model to feel the convolution. (1 mark)

_______________________________________________________________________________

(3) discussing with his classmates on the functions of human brain. (1 mark)

_______________________________________________________________________________

(ii) Describe and explain what would happen to a human if:

(1) part B is damaged; (2 marks)

_______________________________________________________________________________

_______________________________________________________________________________

(2) part C is damaged. (2 marks)

_______________________________________________________________________________



________________________________________________________________________________________

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(iii) The internal structure of part C is the reverse of those in parts A and B. State the difference.

(2 marks)

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##

(i) (1) C (1 mark)

(2) A (1 mark)

(3) A (1 mark)

(ii) (1) Damage of part B would lead to a loss of the ability to maintain balance (1 mark)

because it is the centre for muscular coordination. (1 mark)

(2) Damage of part C would lead to death (1 mark)

because it is the centre of reflex and involuntary actions. (1 mark)

(iii) The outer layer of part C is made up of white matter (1 mark)

while the inner layer is made up of grey matter, which is reverse in parts A and B. (1 mark)

_________

(9 marks)##

|!|EQA01600005|!|

STS Connections

The following diagram shows a motor neurone:

(i) Name structure X. Give ONE reason to explain your answer. (2 marks)

_______________________________________________________________________________

_______________________________________________________________________________

(ii) Structure Y branches from structure X. Suggest TWO cell types which are connected to structure Y.

(2 marks)

_______________________________________________________________________________



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(iii) Name organelle Z. Suggest ONE function of this structure. (2 marks)

_______________________________________________________________________________

_______________________________________________________________________________

(iv) The passage below is about a disease known as multiple sclerosis:

Multiple Sclerosis

Multiple sclerosis is a disease in the central nervous system. The exact cause of this

disease is still unknown, but scientists believe that it is caused by an abnormal response of the

immune system. Thus, it is regarded as a kind of autoimmune disease, meaning that the body

attacks its own cells or tissues. In multiple sclerosis, the myelin sheath of neurones is attacked

and destroyed. As a result, many body functions are affected in patients suffering from multiple

sclerosis.

(1) Apart from the brain, what is the other component of the central nervous system? (1 mark)

_______________________________________________________________________________

(2) State the chemical nature of the myelin sheath. Suggest a function of the myelin sheath other than

increasing the rate of nerve impulse transmission. (2 marks)

_______________________________________________________________________________

_______________________________________________________________________________

(3) Body functions such as the ability to maintain balance are affected. Explain why a patient

suffering from multiple sclerosis fails to maintain body balance. (2 marks)

_______________________________________________________________________________

_______________________________________________________________________________

(4) Suggest a cell type in the immune system that is involved in autoimmune diseases. (1 mark)

_______________________________________________________________________________

##

(i) Axon. (1 mark)

It carries nerve impulses away from the cell body. (1 mark)

(ii) muscle cells (1 mark)

gland (glandular) cells (1 mark)

(iii) Nucleus. (1 mark)

It controls the metabolic activities of the motor neurone /

it contains genetic materials for protein synthesis. (any one) (1 mark)

(iv) (1) Spinal cord. (1 mark)

(2) Fat. (1 mark)

To protect the nerve fibres / to prevent the leakage of nervous signals. (1 mark)

(3) The normal nerve impulse transmission is disrupted. (1 mark)



________________________________________________________________________________________

As a result, nervous signals from the cerebellum (1 mark)

to maintain balance cannot be effectively transmitted to the skeletal muscles. (1 mark)

(any two points from above)

(4) white blood cells (1 mark)

_________

(12 marks)##

|!|EQA01600006|!|

One day, Tommy was cooking in the kitchen with his mum. Tommy carelessly touched a very hot glass of

water.

(i) Based on the outline below, describe the events that took place when Tommy touched the hot glass of

water (stimulus) and then withdrew his hand (response). (5 marks)

_______________________________________________________________________________

_______________________________________________________________________________

_______________________________________________________________________________

_______________________________________________________________________________

_______________________________________________________________________________

_______________________________________________________________________________

(ii) Describe the events that took place when Tommy shouted to ask his mum for help. (3 marks)

_______________________________________________________________________________

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(iii) Describe ONE difference in the nature of motor control involved in (i) and (ii). (1 mark)

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##

(i) The hot glass of water stimulated the heat receptors in the skin of the hand (1 mark)

and the receptors generated nerve impulses. (1 mark)

Nerve impulses were then transmitted from the sensory neurones to

the interneurones and then to motor neurones in the spinal cord. (1 mark)

Nerve impulses subsequently travelled along the motor neurones which

connect to the cells of the biceps. (1 mark)



________________________________________________________________________________________

The biceps then contracted to effect the withdrawal of the hand (1 mark)

upon the arrival of nerve impulses.

(ii) The cerebrum sent out nerve impulses (1 mark)

along motor neurones (1 mark)

to the muscles responsible for speech. (1 mark)

(iii) The motor control in (i) is involuntary while that in (ii) is voluntary. (1 mark)

(accept any reasonable answers)

__________

(9 marks)##

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The following diagram shows part of the central nervous system and the structure of a human leg:

(The diagram is NOT drawn in scale)

(i) Indicate, using the letters in the diagram, the pathway taken by the nerve impulses to effect the

straightening of the leg under conscious control. (1 mark)

_______________________________________________________________________________

(ii) Name structures 1 and 2. State and explain their functions when one is dancing. (6 marks)

_______________________________________________________________________________

_______________________________________________________________________________



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(iii) For nerve impulses to travel via the pathway D C, they need to ‘jump’ across a gap. When nerve

impulses arrive at the end of the axon of neurone 4, chemicals are released and diffuse across the gap.

The end of dendrons of neurone 3 receives the chemicals, and nerve impulses are then initiated and

travel towards the skeletal muscle.

(1) Name the gap between neurones 3 and 4. (1 mark)

_______________________________________________________________________________

(2) It is known that the chemicals are only produced at the end of the axon but not that of the dendron.

What is the importance of this? (1 mark)

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##

(i) A B C (1 mark)

(ii) Structure 1: cerebellum (1 mark)

Structure 2: medulla (1 mark)

Structure 1 is responsible for coordinating the movement of the skeletal muscles (1 mark)

to maintain body balance during the dance. (1 mark)

Structure 2 regulates / increases the rate and depth of breathing and heart rate (1 mark)

to supply more oxygen for skeletal muscle contraction. (1 mark)

(iii) (1) synapse (1 mark)

(2) To ensure the unidirectional transmission of nerve impulses across the synapse

/ from neurones 4 to 3. (1 mark)

_________

(9 marks)##

|!|EQA01600008|!|

The diagram below shows a section of a human brain:



________________________________________________________________________________________

(i) State the significance of the highly folded surface of structure 1. (3 marks)

_______________________________________________________________________________

_______________________________________________________________________________

_______________________________________________________________________________

(ii) What will happen to a human if structure 2 is damaged? (1 mark)

_______________________________________________________________________________

(iii) Name structure 3. State one similarity and one difference between the functions of structure 3 and the

spinal cord. (3 marks)

_______________________________________________________________________________

_______________________________________________________________________________

_______________________________________________________________________________

(iv) Name fluid X and give one function of this fluid. (2 marks)

_______________________________________________________________________________

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##

(i) The surface area of structure 1 is greatly increased (1 mark)

to accommodate more neurones / cell bodies / nerve cells (1 mark)

for better nervous coordination and communication. (1 mark)

(ii) He will be unable to maintain his body balance / make precise movements. (1 mark)

(iii) medulla / medulla oblongata (1 mark)

Both are reflex centres. (1 mark)

Spinal cord is responsible for reflexes in trunks and limbs only

while structure 3 is also responsible for the reflexes in the head e.g. pupil reflex. (1 mark)

(iv) cerebrospinal fluid (1 mark)

It acts as a cushion to absorb shock/

supplies nutrients and oxygen to neurones/

transports metabolic wastes away from neurones/



________________________________________________________________________________________

to prevent collapse of the central nervous system. (1 mark)

__________

(9 marks)##

|!|EQA01600009|!|

The following diagram shows the structure of a neurone:

(i) (1) What type of neurone is it? What is its function? (2 marks)

_______________________________________________________________________________

(2) Name the other two types of neurones which can be found in the body. (1 mark)

_______________________________________________________________________________

(ii) (1) Name the nerve fibres A and C. (1 mark)

_______________________________________________________________________________

(2) State the differences between A and C. (2 marks)

_______________________________________________________________________________

_______________________________________________________________________________

_______________________________________________________________________________

(iii) (1) What is B? (1 mark)

_______________________________________________________________________________

(2) Describe the nature and function of B. (2 marks)

_______________________________________________________________________________

_______________________________________________________________________________

(iv) Where is the cell body of this neurone located in the human body? (1 mark)

_______________________________________________________________________________

(v) There is a gap between one neurone and another. Name this gap and state its function. (2 marks)

_______________________________________________________________________________

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##

(i) (1) It is a sensory neurone. It is responsible for the transmission of nerve impulse from the receptor to

the central nervous system. (2 marks)

(2) motor neurone and interneurone (1/2 mark each) (1 mark)

(ii) (1) A: axon

C: dendron (1/2 mark each) (1 mark)

(2)



________________________________________________________________________________________

A (axon) C (dendron)

- relatively short process

- transmits nerve impulses away

from the cell body to the central

nervous system

- relatively long process

- transmits nerve impulses from the

sense organ to its cell body

(each point 1 mark) (2 marks)

(iii) (1) B is the myelin sheath. (1 mark)

(2) It is a layer of white fatty substance. It acts as an insulator to prevent the nerve impulses from

crossing between the nerve processes. (2 marks)

(iv) The cell body of this neurone is located just outside the central nervous system and is aggregated with

others to form a ganglion. (1 mark)

(v) It is the synapse. It ensures that nerve impulses can only be transmitted from one neurone to another in

one direction. (2 marks)

_________

(12 marks)##

|!|EQA01600010|!|

The following diagram shows the spinal cord (in transverse section) and the right hand of a man. (The parts

are not drawn to the same scale.)

(i) Name the neurones A, B and C. (11/2 marks)

_______________________________________________________________________________

(ii) Give THREE differences between neurones A and C. (3 marks)

_______________________________________________________________________________

_______________________________________________________________________________

_______________________________________________________________________________



________________________________________________________________________________________

_______________________________________________________________________________

(iii) Draw a labelled diagram to show the structure of neurone C. (5 marks)

(iv) A person will normally withdraw his hand when he accidentally touches a hot object. How does this

action differ from a voluntary action? (5 marks)

_______________________________________________________________________________

_______________________________________________________________________________

_______________________________________________________________________________

_______________________________________________________________________________

_______________________________________________________________________________

_______________________________________________________________________________

(v) How would the action mentioned in (iv) change if the nerve fibre has been cut:

(1) at position X? (1 mark)

_______________________________________________________________________________

_______________________________________________________________________________

(2) at position Y? (1 mark)

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##

(i) A - sensory neurone

B - interneurone

C - motor neurone (1/2 mark each) (11/2 marks)

(ii)

A (sensory neurone) C (motor neurone)

- with a longer dendron and a shorter axon


receptor to the central nervous system

- the cell body is in the ganglion which is

- with shorter dendrons and a longer axon


central nervous system to the effector

- the cell body is located in the central



________________________________________________________________________________________

located outside the central nervous

system

nervous system


(iii)

Diagram (2 marks)

Label (1/2 mark each) (3 marks)

(iv) This is a reflex action. (1 mark)

The differences between a reflex action and a voluntary action:

Reflex action Voluntary action

1. Pathway taken by

nerve impulsesnot involving cerebrum involving cerebrum

2. Control automatic, not under control of the will usually slower

3. Speed of response quicker usually slower

4. Response to the

same stimulusalways the same

different, depending on learning

from previous experiences


(v) (1) The person will withdraw his hand but the nerve impulses cannot be transmitted to the brain.

(1 mark)

(2) The person will feel pain but he cannot withdraw his hand immediately. (1 mark)

___________

(161/2 marks)##

|!|EQA01600011|!|

The following diagram shows a vertical section of a human brain:



________________________________________________________________________________________

(i) Describe briefly how the human brain is protected. (3 marks)

_______________________________________________________________________________

_______________________________________________________________________________

_______________________________________________________________________________

_______________________________________________________________________________

(ii) (1) Name structure A. (1 mark)

_______________________________________________________________________________

(2) How is the component of A different from that of the spinal cord? (1 mark)

_______________________________________________________________________________

(3) Why is the surface of A highly convoluted? (2 marks)

_______________________________________________________________________________

_______________________________________________________________________________

(iii) Name structure B. What would happen to a person if structure B were damaged? (3 marks)

_______________________________________________________________________________

_______________________________________________________________________________

_______________________________________________________________________________

(iv) (1) Name the fluid contained in space X. (1 mark)

_______________________________________________________________________________

(2) What are the functions of this fluid? (2 marks)

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##

(i) It is protected by the hard skull/cranium. (1 mark)



________________________________________________________________________________________

It is enclosed by the meninges. (1 mark)

It is bathed in the cerebrospinal fluid which absorbs shock. (1 mark)

(ii) (1) cerebral cortex/cerebrum (1 mark)

(2)

A Spinal cord

Outside Grey matter White matter

OR Inside White matter Grey matter

(1 mark)

(3) to increase the surface area for accommodating a greater number of nerve cells (2 marks)

(iii) B - cerebellum (1 mark)

If B is damaged, he cannot maintain balance and cannot make accurate movements/ lose muscle

coordination. (2 marks)

(iv) (1) cerebrospinal fluid (1 mark)

(2) It nourishes the brain cells. (1 mark)

It serves as a shock absorber. (any acceptable answers) (1 mark)

_________

(13 marks)##



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Extension Section

|!|EQB01600012|!|

* The following flowchart outlines the pathway of nervous signals when Kenneth was watching a horror film:

(i) Where are the light-sensitive cells located? (1 mark)

_______________________________________________________________________________

(ii) In which part of the brain does the interpretation of visual signals take place? (1 mark)

_______________________________________________________________________________

(iii) Nerve fibres in the optic nerve are wrapped up by a fatty substance.

(1) Name the fatty substance. (1 mark)

_______________________________________________________________________________

(2) Suggest ONE function of the fatty substance. (1 mark)

_______________________________________________________________________________

(iv) When watching the film, Kenneth felt frightened and his heart rate increased drastically.

(1) The increase in heart rate was caused by two coordinating systems in the body. Name the TWO

systems and state ONE difference between them. (3 marks)

_______________________________________________________________________________

_______________________________________________________________________________

_______________________________________________________________________________

(2) When a person feels frightened, the increase in heart rate prepares the body to escape from danger.

What is the biological significance of this phenomenon? (5 marks)

_______________________________________________________________________________

_______________________________________________________________________________

_______________________________________________________________________________

_______________________________________________________________________________

_______________________________________________________________________________

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##

(i) retina (1 mark)

(ii) cerebral cortex / cerebrum / visual cortex (1 mark)



________________________________________________________________________________________

(iii) (1) myelin sheath (1 mark)

(2) to protect the nerve fibres

to prevent the leakage of nervous signals

to speed up the rate of transmission of nerve impulses (any one) (1 mark)

(iv) (1) nervous system (1 mark)

hormonal / endocrine system (1 mark)

Any one of the following: (1 mark)

Nervous System Endocrine System

Nature of message nerve impulse hormone

Means of transmission along nerve fibres in the blood

Rate of response produced fast slow

Duration of effects short-term long-term

(2) The increase in heart rate allows more blood supply to the skeletal muscles. (1 mark)

Thus, more nutrients and oxygen are provided to these cells (1 mark)

for the release of a larger amount of energy by respiration. (1 mark)

The large amount of energy is to prepare the body for the vigorous contraction

of skeletal muscles during the subsequent escape. (1 mark)

More blood supply also allows more carbon dioxide and heat to be removed

from the skeletal muscles. (1 mark)

___________

(12 marks)##

|!|EQB01600013|!|

* The diagram below shows some of the organs in a human body:

(i) How does the secretion from organ A help in digestion of beef? Explain your answer. (4 marks)

_______________________________________________________________________________


A

B


________________________________________________________________________________________

_______________________________________________________________________________

_______________________________________________________________________________

_______________________________________________________________________________

(ii) Organ B is said to be a mixed gland because it produces both exocrine and endocrine secretions.

(1) What exocrine secretion does organ B produce? (1 mark)

_______________________________________________________________________________

(2) Organ B produces two endocrine secretions. Give ONE structural similarity and ONE functional

difference between these two secretions. (2 marks)

_______________________________________________________________________________

_______________________________________________________________________________

(3) State another mixed gland in humans. Explain your answer. (3 marks)

_______________________________________________________________________________

_______________________________________________________________________________

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##

(i) The secretion contains protease (1 mark)

that digests the proteins in beef into polypeptides. (1 mark)

It contains gastric acid / hydrochloric acid / it is acidic, (1 mark)

providing an optimum pH for the protease to act on the proteins. (1 mark)

(ii) (1) pancreatic juice (1 mark)

(2) Both insulin and glucagon are proteins / polypeptides. (1 mark)

Insulin stimulates the liver cells to convert excess glucose into glycogen

while glucagon stimulates the breakdown of glycogen in the liver cells to glucose. (1 mark)

(3) Testis. (1 mark)

It produces sperms which are released into the sperm ducts (exocrine) (1 mark)

and male sex hormones which are released into the blood (endocrine). (1 mark)

OR

Ovary. (1 mark)

It produces eggs which are released into the oviducts (exocrine) (1 mark)

and female sex hormones which are released into the blood (endocrine) (1 mark)

__________

(10 marks)##

|!|EQA01600014|!|

The following graphs show the glucose, insulin and glucagon concentrations in blood of a normal person

before and after a meal rich in carbohydrates. The units of the three graphs are different and arbitrary.



________________________________________________________________________________________

(i) State TWO processes that resulted in the increase in the blood glucose level after hour 1. (2 marks)

_______________________________________________________________________________

(ii) State and explain TWO causes for the decrease in blood glucose level 1 hour after the meal.

(4 marks)

_______________________________________________________________________________

_______________________________________________________________________________

_______________________________________________________________________________

_______________________________________________________________________________

(iii) Explain why the level of glucagon rose between hour 3 and hour 5. (2 marks)

_______________________________________________________________________________

_______________________________________________________________________________

(iv) A student wrote the following passage:

Insulin and glucagon are protein in nature. They are produced in the pancreas and released

through the pancreatic ducts into the blood. Both are enzymes that regulate the blood glucose

level. They act on the liver cells and their actions are antagonistic.



________________________________________________________________________________________

Give TWO reasons why the above passage is wrong. (2 marks)

_______________________________________________________________________________

_______________________________________________________________________________

##

(i) Digestion and absorption of the carbohydrates. (2 marks)

(ii) Conversion of excess blood glucose into glycogen in the liver (1 mark)

due to increased level of insulin and decreased level of glucagons. (1 mark)

Uptake of glucose by body cells (1 mark)

for liberation of energy by respiration. (1 mark)

(iii) The decrease in blood glucose level (1 mark)

stimulated the pancreas to release more glucagon. (1 mark)

(iv) Insulin and glucagon are released into the blood directly from the pancreatic cells that

produce them, and not through the pancreatic duct. (1 mark)

Insulin and glucagon are hormones, not enzymes. (1 mark)

__________

(10 marks)##

|!|EQA01600015|!|

Sandra suffers from diabetes. She needs injections of a hormone X to keep her blood glucose level stable.

(i) (1) Name hormone X. (1 mark)

_______________________________________________________________________________

(2) State the chemical nature of hormone X. (1 mark)

_______________________________________________________________________________

(3) State the target organ of hormone X. (1 mark)

_______________________________________________________________________________

(4) State the response which takes place in the target organ. (1 mark)

_______________________________________________________________________________

(ii) Name the mechanism which regulates the secretion of hormone X in a healthy person. (1 mark)

_______________________________________________________________________________



________________________________________________________________________________________

(iii) Complete the following table which compares and/or contrasts hormone X and withdrawal reflex.

(4 marks)

Hormone X W ithdrawal reflex

Method of

transmission1 mark each

Duration of

effect1 mark each

##

(i) (1) insulin (1 mark)

(2) protein in nature (1 mark)

(3) liver (1 mark)

(4) Blood glucose is converted to glycogen for storage. (1 mark)

(ii) negative feedback mechanism (1 mark)

(iii)

Hormone X W ithdrawal reflex

Method of

transmission

It is carried by blood

vessels.

Nerve impulse is transmitted

along nerve fibres.1 mark each

Duration of

effect

long-term effect short-term effect1 mark each

(4 marks)

_________

(9 marks)##


chapter 16 question

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