Control and Coordination MCQ
1. Which of the following statements is correct about receptors?
(a) Gustatory receptors detect taste while olfactory receptors detect smell
(b) Both gustatory and olfactory receptors detect smell
(c) Auditory receptors detect smell and olfactory receptors detect taste
(d) Olfactory receptors detect taste and gustatory receptors smell
Ans. (a) Gustatory receptors detect taste while olfactory receptors detect smell
2. Electrical impulse travels in a neuron from
(a) Dendrite→ axon →axonal end →cell body
(b) Cell body →dendrite →axon →axonal end
(c) Dendrite →cell body →axon →axonal end
(d) Axonal end →axon →cell body →dendrite
Ans. (c) Dendrite→ cell body→ axon →axonal end
Explanation: Dendrites of a neuron receive electrical impulse from axonal end of another neuron. After that, electrical impulse travels through cell body, axon; to the axonal end.
3. In a synapse, chemical signal is transmitted from
(a) dendritic end of one neuron to axonal end of another neuron
(b) axon to cell body of the same neuron
(c) cell body to axonal end of the same neuron
(d) axonal end of one neuron to dendritic end of another neuron
Ans. (d) axonal end of one neuron to dendritic end of another neuron
Explanation: Refer to previous question’s explanation.
4. In a neuron, conversion of electrical signal to a chemical signal occurs at/in
(a) cell body
(b) axonal end
(c) dendritic end
(d) axon
Ans. (b) Axonal end
Explanation: At the axonal end, electrical impulse sets off the release of some chemicals; called neurotransmitters. These chemicals enter the dendrite of another neuron to transmit the signal.
5. Which is the correct sequence of the components of a reflex arc?
(a) Receptors→ Muscles→ Sensory neuron→ Motor neuron→ Spinal cord
(b) Receptors→ Motor neuron →Spinal cord →Sensory neuron →Muscle
(c) Receptors →Spinal cord →Sensory neuron →Motor neuron →Muscle
(d) Receptors →Sensory neuron →Spinal cord →Motor neuron →Muscle
Ans. (d) Receptors →Sensory neuron →Spinal cord →Motor neuron →Muscle
Explanation: In a reflex arc, sensory neurons pick signals from receptors. These signals are then sent to the spinal cord; from where they go to muscle via motor neuron.
6. Which of the following statements are true?
(i) Sudden action in response to something in the environment is called reflex action
(ii) Sensory neurons carry signals from spinal cord to muscles
(iii) Motor neurons carry signals from receptors to spinal cord
(iv) The path through which signals are transmitted from a receptor to a muscle or a
gland is called reflex arc
(a) (i) and (ii)
(b) (i) and (iii)
(c) (i) and (iv)
(d) (i), (ii) and (iii)
Ans. (c) (i) and (iv)
Explanation: Sensory neurons carry signals from muscles to spinal cord, hence statements (ii) and (iii) are incorrect.
7. Which of the following statements are true about the brain?
(i) The main thinking part of brain is hind brain
(ii) Centres of hearing, smell, memory, sight etc are located in fore brain.
(iii) Involuntary actions like salivation, vomiting, blood pressure are controlled by the medulla in the hind brain
(iv) Cerebellum does not control posture and balance of the body
(a) (i) and (ii)
(b) (i), (ii) and (iii)
(c) (ii) and (iii)
(d) (iii) and (iv)
Ans. (c) (ii) and (iii)
Explanation: The main thinking part of the brain is forebrain and hence statement (i) is incorrect. Cerebellum controls posture and balance of the body and hence statement (iv) is incorrect.
8. Posture and balance of the body is controlled by
(a) cerebrum
(b) cerebellum
(c) medulla
(d) pons
Ans. (b) Cerebrum
Explanation: Refer to previous question’s explanation.
9. Spinal cord originates from
(a) cerebrum
(b) medulla
(c) pons
(d) cerebellum
Ans. (b) medulla
10. The movement of shoot towards light is
(a) geotropism
(b) hydrotropism
(c) chemotropism
(d) phototropism
Ans. (d) phototropism
Explanation: The term ‘phototropism’ is composed of two terms. ‘Photo’ means light and ‘tropism’ means growth.
11. The main function of abscisic acid in plants is to
(a) increase the length of cells
(b) promote cell division
(c) inhibit growth
(d) promote growth of stem
Ans. (c) Inhibit growth
12. Which of the following is not associated with growth of plant?
(a) Auxin
(b) Gibberellins
(c) Cytokinins
(d) Abscisic acid
Ans. (d) Abscisic acid
Explanation: It is an inhibitory hormone and hence is not associated with growth of plant.
13. Iodine is necessary for the synthesis of which hormone?
(a) Adrenaline
(b) Thyroxin
(c) Auxin
(d) Insulin
Ans. (b) Thyroxin
Explanation: This is the reason, deficiency of iodine results in hypothyroidism.
14. Choose the incorrect statement about insulin
(a) It is produced from pancreas
(b) It regulates growth and development of the body
(c) It regulates blood sugar level
(d) Insufficient secretion of insulin will cause diabetes
Ans. (b) It regulates growth and development of the body
Explanation: Insulin has no role to play in growth and development of the body.
15. Select the mis-matched pair
(a) Adrenaline: Pituitary gland
(b) Testosterone: Testes
(c) Estrogen: Ovary
(d) Thyroxin: Thyroid gland
Ans. (a) Adrenaline: Pituitary gland
Explanation: Adrenaline is secreted by adrenal gland.
