CONTROL AND COORDINATION IN LIVING ORGANISMS - I : MCQs AND SHORT ANSWERS

*INDEX-TOPIC SEARCH

MULTIPLE-CHOICE QUESTIONS

SELECT THE CORRECT ALTERNATIVE:

1. ______ is the complimentary system of nervous system.
   
   
   
   1. Circulatory system
   2. Endocrine system
   3. Lymphatic system
   4. Skeletal system
      
   
   
2. Plant hormones are called ______.
   
   
   
   1. hypohormones
   2. metahormones
   3. phytohormones
   4. cytohormones
      
   
   
3. The leaves of mimosa are sensitive to ______.
   
   
   
   1. light
   2. touch
   3. heat
   4. smell
      
   
   
4. A sunflower plant bends towards the sun. It is ______ response.
   
   
   
   1. Thigmonastic
   2. seismonastic
   3. thermonastic
   4. photonastic
      
   
   
5. All multicellular organisms, except ______, have well-developed nervous system.
   
   
   
   1. porifera
   2. mammals
   3. arthropoda
   4. insecta
      
   
   
6. Nerve mass in invertebrates is called ______.
   
   
   
   1. brain
   2. neuron
   3. ganglion
   4. pelvis
      
   
   
7. Hormones are secreted by ______.
   
   
   
   1. endocrine glands
   2. blood
   3. midbrain
   4. liver
      
   
   
8. The space between meninges is filled with ______.
   
   
   
   1. lymph
   2. blood plasma
   3. cerebrospinal fluid
   4. ACTH
      
   
   
9. ______ is not the part of hindbrain.
   
   
   
   1. cerebellum
   2. pons
   3. medulla oblongata
   4. cerebrum
      
   
   
10. ______ protects spinal cord.
    
    
    
    1. Cranium
    2. Vertebral column
    3. Skull
    4. Ribs
       
    
    
11. ______ pairs of spinal nerves arise from spinal cord.
    
    
    
    1. 21
    2. 31
    3. 32
    4. 42
       
    
    
12. Which of the following organs is not controlled by autonomous nervous system ?
    
    
    
    1. Heart
    2. Uterus
    3. Glands
    4. Eyes
       
    
    
13. The effects of sympathetic and parasympathetic nervous systems are ______.
    
    
    
    1. complimentary
    2. contradictory
    3. complimentary and contradictory
    4. none of above.
       
    
    
14. Endocrine glands ______.
    
    
    
    1. secrete plasma
    2. secrete nutrients
    3. secrete hormones
    4. secrete antibodies
       
    
    
15. Acetylcholine ______.
    
    
    
    1. increases the speed of conduction of impulses
    2. decreases the speed of conduction of impulses
    3. quickens the effect of growth hormones
    4. controls pituitary gland
       
    
    
16. ______ is called the master gland.
    
    
    
    1. Pineal
    2. Pituitary
    3. Thyroid
    4. Thymus
       
    
    
17. ______ hormone regulates ionic balance.
    
    
    
    1. Vasopressin
    2. Thyroxin
    3. Glucagon
    4. Testosterone
       
    
    
18. ______ is the hormone responsible for development of female characteristics.
    
    
    
    1. Adrenalin
    2. Testosterone
    3. Thyroxin
    4. Progesterone
       
    
    
19. ______ is responsible for lowering glucose level in blood.
    
    
    
    1. Glucagon
    2. Oxytocin
    3. Insulin
    4. Adrenalin
       
    
    
20. ______ is responsible for increasing glucose level in blood.
    
    
    
    1. Glucagon
    2. Oxytocin
    3. Insulin
    4. Adrenalin
       
    
    
21. Prolactin regulates ______.
    
    
    
    1. blood pressure
    2. heartbeat
    3. mammary glands
    4. glucose metabolism
       
    
    
22. Nerve net is found in ______.
    
    
    
    1. sponges
    2. hydra
    3. earthworm
    4. cockroach
       
    
    
23. Which multicellular organism lacks the nervous system ?
    
    
    
    1. Hydra
    2. Locust
    3. Sponges
    4. Tapeworm
       
    
    
24. Which hormone functions as a growth promotor ?
    
    
    
    1. Auxin
    2. Ethylene
    3. Abscisic acid
    4. Both B and C
       
    
    
25. Which of the following shows thigmonastic response ?
    
    
    
    1. Sun flower
    2. Insectivorous plants
    3. Lotus
    4. Bryophyllum
       
    
    
26. Which two organs are connected by pons with the help of transverse band of nerves ?
    
    
    
    1. Nerves of brain and spinal cord
    2. Both the cerebral hemispheres
    3. Cerebellum and central nervous system
    4. Sympathetic and parasympathetic
       
    
    
27. 
    
    
    
    4. 
       
    
    

ANSWERS TO MCQs:

(1) B (2) C (3) B (4) D (5) A (6) C (7) A (8) C (9) D (10) B (11) B (12) D (13) C (14) C (15) A (16) B (17) A (18) D (19) C (20) A (21) C (22) B (23) C (24) A (25) B (26) C

SHORT QUESTIONS

ANSWER IN SHORT:

1. What is a stimulus ?
   
        ANS : Any environmental factor that affects a living organism by showing changes is called a stimulus.
   
   
2. What is the structural and functional unit of the nervous system in multicellular organisms ?
   
        ANS : Neuron is the structural and functional unit of the nervous system in multicellular organisms.
   
   
3. What does the nervous system do ?
   
        ANS : The nervous system controls and coordinates various activities in the body of an organism.
   
   
4. Mention some factors (stimuli) to which plants respond.
   
        ANS : Light, touch, water, gravitational force, insects, chemicals, etc are some stimuli to which plants respond.
   
   
5. Mention some plant hormones.
   
        ANS : Auxin, gibberellin, cytokinin, abscisic acid, ethylene, etc are some plant hormones.
   
   
6. Mention growth hormones of plants.
   
        ANS : Auxin, gibberellin and cytokinin are growth hormones of plants.
   
   
7. Which hormones in plants are responsible for ripening of fruits and shedding of leaves ?
   
        ANS : Abscisic acid and ethylene are responsible for ripening of fruits and shedding of leaves.
   
   
8. Which plant hormones retard growth ?
   
        ANS : Abscisic acid and ethylene retard growth.
   
   
9. What is tropism ?
   
        ANS : The movement of curvature of plants in the direction of stimulus is known as tropism.
   
   
10. What is phototropism ?
    
         ANS : The bending of a growing plant towards unidirectional light as a response to the illumination is called phototropism.
    
    
11. What is geotropism ?
    
         ANS : Geotropism is a growth response of a plant to the force of gravitation (gravity) in which the roots show the downward movement.
    
    
12. What is hydrotropism ?
    
         ANS : Hydrotropism is a growth response of a plant towards water shown by the growth of roots towards water.
    
    
13. What is chemotropism ?
    
         ANS : Chemotropism is a growth response (movement) of a plant towards certain chemicals.
    
    
14. Give an example of chemotropism.
    
         ANS : The germination of pollen grains and the development of pollen tube as a response to the chemicals secreted by the stigmatic surface is an example of chemotropism.
    
    
15. Define : Nastic movement.
    
         ANS : A response of a plant to an external stimulus independent of its direction is called nastic movement.
    
    
16. What is thigmonastic response ?
    
         ANS : The bending down or curling up of insectivorous plants, when touched by insects, is called thigmonastic movement.
    
    
17. What is photoperiodism ?
    
         ANS : Photoperiodism is the response of some plants to the duration of light which mainly affects the flowering and germination in plants.
    
    
18. Which specialised pigment is responsible for the photoperiodic response by plants ?
    
         ANS : Phytochrome is responsible for the photoperiodic response by plants.
    
    
19. Which organisms possess nerve net ?
    
         ANS : Hydra and other cnidarians possess nerve net.
    
    
20. What does the nervous system of insects consist of ?
    
         ANS : The nervous system of insects consists of a bilobed nerve mass (brain), nerve cord and nerve ganglia.
    
    
21. What is the function of receptors in nervous system ?
    
         ANS : Receptors receive the stimuli and pass the message to the brain with the help of sensory neuron.
    
    
22. What is sensory neuron ?
    
         ANS : Sensory neuron is a nerve cell which receives the stimuli from receptor and passes the message to the brain.
    
    
23. What is motor neuron ?
    
         ANS : Motor neuron is a nerve cell which receives information from brain, transmits it to effector organ and stimulates it to respond.
    
    
24. Through what do hormones reach the target organ ?
    
         ANS : Hormones reach the target organ through blood.
    
    
25. What protects brain in human beings ?
    
         ANS : A bony box in the skull called cranium and three membranes called meninges protect the brain in human beings.
    
    
26. What is the function of cerebrospinal fluid ?
    
         ANS : Cerebrospinal fluid acts as a cushion and protects the brain from mechanical shocks.
    
    
27. Mention three regions of brain.
    
         ANS : The three regions of brain are : forebrain, midbrain and hindbrain.
    
    
28. What does forebrain consist of ?
    
         ANS : Forebrain consists of cerebrum and olfactory lobes.
    
    
29. Mention the regions of cerebrum.
    
         ANS : The regions of cerebrum are : frontal lobe, parietal lobe, temporal lobe and occipital lobe.
    
    
30. Mention the centres located in frontal lobe region.
    
         ANS : Frontal lobe possesses the centres for voluntary muscular activities.
    
    
31. Mention the centres located in parietal lobe region.
    
         ANS : Parietal lobe possesses the centres for temperature control, smell and touch.
    
    
32. Mention the centres located in temporal lobe region.
    
         ANS : Temporal lobe possesses the centres for auditory and olfactory reception.
    
    
33. Mention the centres located in occipital lobe region.
    
         ANS : Occipital lobe possesses the centre for visual reception.
    
    
34. Mention the regions of the midbrain.
    
         ANS : The midbrain has the regions for visual reception, auditory reception and touch.
    
    
35. Mention the parts of brainstem.
    
         ANS : Brainstem consists of midbrain, pons and medulla oblongata.
    
    
36. What does hindbrain consist of ?
    
         ANS : Hindbrain consists of cerebellum, pons and medulla oblongata.
    
    
37. What is the function of cerebellum ?
    
         ANS : Cerebellum controls the rythmic movement of muscles, body balance and posture.
    
    
38. Mention the centres possessed by medulla oblongata.
    
         ANS : Medulla oblongata possesses the centres to regulate heartbeat, breathing, blood pressure, sneezing, vomiting, coughing, swallowing, hiccups, etc.
    
    
39. What is reflex action ?
    
         ANS : Reflex action is an unconscious and involuntary response of effectors to a stimulus.
    
    
40. What is reflex arc ?
    
         ANS : Reflex arc is the pathway through which a message from receptors is relayed by sensory nerves to the spinal cord which sends to effectors for response via motor nerve.
    
    
41. Which organ performs reflex action ? When ?
    
         ANS : The spinal cord performs reflex action when the brain is busy or at rest.
    
    
42. What is meant by autonomous nervous system ?
    
         ANS : The system responsible for the control of organs located in the body cavity without the awareness of the brain is called autonomous nervous system.
    
    
43. Mention the organs controlled by the autonomous nervous system.
    
         ANS : Heart, blood vessels, glands, uterus, coelomic organs, etc are controlled by the autonomous nervous system.
    
    
44. Mention two types of autonomous nervous system.
    
         ANS : Sympathetic nervous system and parasympathetic nervous system are the two types of autonomous nervous system.
    
    
45. Write the names of important glands.
    
         ANS : Hypothalamus, pituitary, pineal, thyroid, parathyroid, thymus, pancreas, adrenal, testis, ovary, etc are important glands.
    
    
46. Which gland is called the master gland ?
    
         ANS : Pituitary gland is called the master gland.
    
    
47. Why is pituitary gland called the master gland ?
    
         ANS : Pituitary gland is called the master gland because it regulates the secretion of hormones by other glands.
    
    
48. What controls the functioning of pituitary gland ?
    
         ANS : The secretion of hypothalamus controls the functioning of pituitary gland.
    
    
49. What is the function of trophic hormones ?
    
         ANS : Trophic hormones regulate the secretion from other endocrine glands.
    
    
50. Which hormone controls male characteristics ?
    
         ANS : Testosterone controls the male characteristics.
    
    
51. What is the function of parathyroid hormone ?
    
         ANS : Parathyroid hormone regulates the level of calcium and phosphate in blood.
    
    
52. Name growth inhibitors in plants.
    
         ANS : Abscisic acid and ethylene are growth inhibitors in plants.
    
    
53. Which structure protects brain ?
    
         ANS : The structure consisting of cranium and three membranes called meninges having CSF (cerebrospinal fluid) in between them protects brain.
    
    
54. How are ganglia formed ?
    
         ANS : Ganglia are formed by the condensation of nerve nets at some junction in the body of insects.
    
    
55. Explain the importance of cerebrospinal fluid.
    
         ANS :Cerebrospinal fluid between the meninges of brain act as a cushion and protect the brain against mechanical shock.
    
    
56. What is the role of phytochrome in plants ?
    
         ANS :Phytochrome is a specialized pigment present in plants which plays an important role in control and coordination of plants with environmental stimuli.
    
    
57.