Form 5 BiologyChapter 12 Coordination and Response

Objective Questions

1 Which part of the brain is the first to be affected by alcohol isA the cerebrumB the cerebellumC the pituitary glandD the medulla oblongata

2 In the human spinal cord, the motor neurone cell body is located in A the dorsal rootB the ventral rootC the white matterD the grey matter

3 The narrow space between the branches of an axon and a neurone dendrite is known as A the neurolemmaB the dendronC the synapseD the Ranvier node

4 The part of the nervous system that maintains the body balance and coordinates muscle movement isA the medulla oblongataB the cerebellumC the cerebrumD the spinal cord

5 Which of the following is the correct sequence of a reflex action?A Effector sensory neurone intermediate neurone motor neurone receptorB Receptor motor neurone sensory neurone intermediate neurone effectorC Receptor effector sensory neurone intermediate neurone motor neuroneD Receptor sensory neurone intermediate neurone motor neurone effector

6 When a person suddenly wakes up from a nightmare, his heartbeat rate will increase. This is caused by the secretion produced by A the pituitary glandB the adrenal glandC the thyroid glandD the pancreas

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7 After an injection of iodine is administered, the iodine will gather at A the pituitary gland B the pancreasC the adrenal glandD the thyroid gland

8 When blood flows through the nephron of the human kidney, a few processes will occur to the urine. What are the processes that occur on the following substances in the kidney?

Blood in the Bowman capsule

Glucose in the proximal loop tubule

Salt in the loop of Henle

A Diffusion Active transport ReabsorptionB Ultrafiltration Active transport Active transportC Diffusion Reabsorption OsmosisD Ultrafiltration Reabsorption Active transport

9 When the body temperature rises, what is the action taken by our body? Blood capillary Sweat gland Urine production

A Vasoconstriction Active IncreaseB Vasodilation Active DecreaseC Vasoconstriction Not active DecreaseD Vasodilation Not active Increase

10 Growth hormone deficiency in a person’s body will causeA dwarfism B cretinism

C myxoedemaD gigantism

11 What will happen to a rat whose pancreas has been operated out?I Glucagon concentration in the blood becomes higher than normalII Urine contains glucoseIII Glucose concentration in the blood becomes lower than normalIV Glycogen in the liver decreasesA II and III onlyB II and IV onlyC II, III and IV onlyD I, II, III and IV

12 Which of the following statements about the effect of drugs on a person’s coordination is true?I Disrupts the function of the nervous systemII Causes mental damageIII Loss of the ability to think and considerIV Causes the tightening of the veins in the abdomen and feetA I and III only C I, III and IV onlyB I, II and III only D I, II, III and IV

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13 What is the effect of alcohol intake on the nerve impulse transmission of a person?I Disable the medulla oblongata II Stimulate the central nervous systemIII Causes inconsistency in muscle coordinationIV Slows down the brain functions A III and IV onlyB I, II and IV onlyC I, III and IV onlyD II, III and IV only

14 A high auxin concentration will causeI the root cell elongation to be disruptedII the shoot cell to elongate quicklyIII the cell to lose water and become flaccid IV the development of the fruit without fertilisationA III and IV onlyB I, II and IV onlyC I and II onlyD II, III and IV

15 Figure 1 shows the result of a test to determine the response of the shoot towards light at different conditions.

(A) (B) (C)Figure 1

The conclusion from this test is that I the shoot end displays positive phototropismII the hormones cause accelerated growth at the side without lightIII the mica plate prevents the flow of hormones from the shoot endIV light slows down growthA I, II and III onlyB I and III onlyC II and IV onlyD IV only

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(A) The mica plate separates the shoot end into two parts(B) The shoot end without the mica plate(C) The mica plate is in the same direction as the light

Structured Questions

1 Figure 1 shows the cross-section of the human spinal cord.

Figure 1

(a) (i) Write the general name for the structure labelled P and Q. (ii) Give a reason for your answer.

(b) What is meant by reflex action?

(c) Give an example of (i) a reflex that involves two neurones:(ii) a reflex that involves three neurones:

(d) (i) Name S, where the nerve cells meet.(ii) Why is S important to the reflex arc curve?

(e) What is the function of the nerve cell that is labelled R?

2 Figure 2 shows the endocrine system in the body of a woman.

Figure 2

(a) Name the endocrine glands that labelled T, V, X, U and W.

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(b) (i) What is the secretion produced by the endocrine gland?(ii) How does this secretion reach the other parts of the body?

(c) (i) State the endocrine gland whose function will be disrupted when a child consumes a diet that lacks iodine.

(ii) Name the disease that the child may suffer from.

(d) How does the secretion of gland U control the stimulating hormone production by gland T?

(e) (i) Which gland secretes insulin?(ii) Name the disease that results from a lack of insulin in a person’s body.(iii) How is a person suffering from the disease stated in e(ii) treated?

Essay Question

(a) Explain the tropism response in plants.(b) List the usage of the following hormones in the field of agriculture:

(i) Auxin(ii) Gibberellins and ethylene

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AnswersObjective Questions1 A2 C3 C4 B5 D6 B7 D8 B

9 B10 A11 B12 D13 C14 C15 D

Structured Questions1 (a) (i) P: Receptor organ

Q: Effector organ(ii) P receives stimulation from the outside and produces nerve impulses through the

sensory neurone to the interneurone. Q produces a response towards the stimuli after receiving the nerve impulse from the spinal cord.

(b) The response occurs spontaneously and automatically without involving the brain.

(c) (i) Knocking of the knee (ii) Pulling the hand from a hot object

(d) (i) Synapse (ii) Allows the transmission of impulses from on neurone to other neurone.

(e) Carries impulses along the spinal cord to the brain.

2 (a) T: Pituitary glandV: PancreasX: OvaryU: Thyroid glandW: Adrenal gland

(b) (i) Hormones(ii) Carried by the blood

(c) (i) Thyroid gland(ii) Cretinism

(d) Through the negative feed back system

(e) (i) Pancreas(ii) Diabetes mellitus(iii) Through the injection of insulin hormone

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Essay Question(a) Tropism response is the response of a certain part of the plant in a direction

determined by the stimuli. The response of a certain part of a plant towards the direction of the stimuli is

known as positive tropism. The response of a certain part of a plant away from the stimuli is known as negative

tropism. Four types of tropism response are phototropism, geotropism, hydrotropism, and

thigmotropism.

Phototropism response The stimulus for this type of response is light. The plant shoot that bends towards the direction of the light shows positive

phototropism. The plant root that grows away from the light and shows negative phototropism.

Geotropism response Gravitational force is the stimuli for this type of response. The plant shoot grows upwards, therefore showing negative geotropism. The plant root grows downwards, therefore showing positive geotropism.

Hydrotropism response A type of plant growth response towards water stimuli. The root grows towards the water, therefore showing positive hydrotropism. This type of response helps the plant to obtain sufficient water for growth.

Thigmotropism This response can be observed on plants with soft stems, which respond towards

touch stimuli. The clinging tendril or soft stem of plants entwine around objects that are touched,

therefore showing positive thigmostropism.

(b) (i) The use of auxins in the field of agriculture: Stimulates the development of the ovary into a fruit, after fertilisation As a weed poison that is used in grain fields, animal grazing fields, and gardens. Stimulate root formation on the stem cuttings that have difficulty in producing

roots. Slow down the budding of potatoes during their storage. Prevent leaves and young fruits from falling.

(ii) The use of gibberellins in the field of agriculture:

Overcome the problem of dwarfism in plants. Induce the production of normal fruits but without seeds. Produce male flowers that are infertile in order to prevent self pollination. The mixture of gibberellins and auxins is used to induce the production of very

big fruits.

The use of ethylene in the field of agriculture: Stimulates the ripening of fruits. Stimulate the simultaneous flowering of plants in the farm.

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