Class 10 Science NCERT MCQs-Chapter 6-Control and Coordination
NCERT MCQs of Class 10 Science, Chapter 5, Control and Coordination
1) Which of the following is the functional unit of the nervous system?
(a) Brain
(b) Neuron
(c) Spinal cord
(d) Synapse
Answer: (b) Neuron
Explanation: Neurons are the basic units of the nervous system that transmit information through electrical and chemical signals.
2) Which part of the brain controls voluntary actions?
(a) Cerebrum
(b) Cerebellum
(c) Medulla
(d) Hypothalamus
Answer: (a) Cerebrum
Explanation: The cerebrum is the largest part of the brain and is responsible for voluntary actions, thinking, memory, and decision-making.
3) What is the main function of the cerebellum?
(a) Control heart rate
(b) Maintain posture and balance
(c) Regulate emotions
(d) Produce hormones
Answer: (b) Maintain posture and balance
Explanation: The cerebellum coordinates muscle movements and helps maintain posture and balance.
4) Which hormone regulates sugar levels in the blood?
(a) Insulin
(b) Thyroxine
(c) Adrenaline
(d) Estrogen
Answer: (a) Insulin
Explanation: Insulin, produced by the pancreas, helps regulate blood glucose levels by facilitating the uptake of glucose into cells.
5) What is the role of sensory neurons?
(a) Carry impulses to muscles
(b) Carry impulses to the central nervous system
(c) Carry impulses between neurons
(d) Interpret sensory information
Answer: (b) Carry impulses to the central nervous system
Explanation: Sensory neurons transmit sensory information from receptors to the central nervous system.
6) What is a synapse?
(a) A type of neuron
(b) A junction between two neurons
(c) A part of the brain
(d) A hormone
Answer: (b) A junction between two neurons
Explanation: A synapse is the gap between two neurons where nerve impulses are transmitted chemically or electrically.
7) Which gland is referred to as the ‘master gland’?
(a) Thyroid gland
(b) Pituitary gland
(c) Adrenal gland
(d) Pancreas
Answer: (b) Pituitary gland
Explanation: The pituitary gland regulates the functions of other endocrine glands and is hence called the 'master gland.'
8) Which of the following is an involuntary action?
(a) Writing
(b) Walking
(c) Breathing
(d) Playing
Answer: (c) Breathing
Explanation: Breathing is controlled involuntarily by the medulla oblongata, although it can also be consciously regulated.
9) What is the function of the medulla oblongata?
(a) Control reflex actions
(b) Maintain posture
(c) Regulate involuntary actions like heartbeat and breathing
(d) Interpret sensory information
Answer: (c) Regulate involuntary actions like heartbeat and breathing
Explanation: The medulla oblongata controls involuntary functions such as heart rate, respiration, and digestion.
10) Which plant hormone promotes cell elongation?
(a) Auxin
(b) Cytokinin
(c) Gibberellin
(d) Ethylene
Answer: (a) Auxin
Explanation: Auxin stimulates cell elongation and is responsible for directional growth in plants.
11) What is the function of motor neurons?
(a) Transmit signals from receptors to the brain
(b) Transmit signals from the brain to effectors (muscles or glands)
(c) Interpret sensory signals
(d) Carry impulses between sensory and interneurons
Answer: (b) Transmit signals from the brain to effectors (muscles or glands)
Explanation: Motor neurons carry signals from the central nervous system to muscles or glands to initiate a response.
12) Which part of the brain is involved in maintaining balance and coordination?
(a) Cerebrum
(b) Cerebellum
(c) Hypothalamus
(d) Medulla
Answer: (b) Cerebellum
Explanation: The cerebellum coordinates voluntary movements and helps maintain balance and posture.
13) What is the role of thyroxine in the human body?
(a) Regulates blood sugar levels
(b) Controls metabolic rate
(c) Aids in muscle contraction
(d) Regulates calcium levels in the blood
Answer: (b) Controls metabolic rate
Explanation: Thyroxine, produced by the thyroid gland, regulates metabolism in the body.
14) Which hormone is known as the ‘stress hormone’?
(a) Insulin
(b) Adrenaline
(c) Thyroxine
(d) Melatonin
Answer: (b) Adrenaline
Explanation: Adrenaline, secreted by the adrenal glands, prepares the body for stress by increasing heart rate and energy supply.
15) What is phototropism in plants?
(a) Movement towards light
(b) Movement away from light
(c) Movement towards gravity
(d) Movement towards water
Answer: (a) Movement towards light
Explanation: Phototropism is the directional growth of plants in response to light, guided by auxins.
16) Which part of the nervous system controls reflex actions?
(a) Brain
(b) Spinal cord
(c) Sensory neurons
(d) Motor neurons
Answer: (b) Spinal cord
Explanation: Reflex actions are rapid responses to stimuli controlled by the spinal cord without involving the brain.
17) Which hormone is responsible for the ripening of fruits?
(a) Auxin
(b) Cytokinin
(c) Ethylene
(d) Gibberellin
Answer: (c) Ethylene
Explanation: Ethylene is a plant hormone that promotes fruit ripening and regulates other physiological processes.
18) What is the structural and functional unit of the kidney?
(a) Neuron
(b) Nephron
(c) Glomerulus
(d) Ureter
Answer: (b) Nephron
Explanation: Nephrons are the basic units of the kidney, responsible for filtering blood and forming urine.
19) Which plant hormone is responsible for breaking seed dormancy?
(a) Gibberellin
(b) Auxin
(c) Cytokinin
(d) Ethylene
Answer: (a) Gibberellin
Explanation: Gibberellins promote seed germination by breaking dormancy and stimulating growth processes.
20) Which gland secretes growth hormone?
(a) Thyroid gland
(b) Pituitary gland
(c) Adrenal gland
(d) Pancreas
Answer: (b) Pituitary gland
Explanation: The pituitary gland secretes growth hormone, which regulates growth and development in the body.
21) What is geotropism in plants?
(a) Movement towards water
(b) Growth in response to gravity
(c) Movement towards light
(d) Growth in response to touch
Answer: (b) Growth in response to gravity
Explanation: Geotropism refers to the growth of plant parts either towards (positive geotropism) or away from (negative geotropism) gravity.
22) Which of the following controls water balance in plants?
(a) Auxin
(b) Cytokinin
(c) Abscisic acid
(d) Ethylene
Answer: (c) Abscisic acid
Explanation: Abscisic acid helps regulate water balance in plants by closing stomata during water scarcity.
23) Which organ is primarily responsible for reflex actions?
(a) Brain
(b) Heart
(c) Spinal cord
(d) Pancreas
Answer: (c) Spinal cord
Explanation: Reflex actions are controlled by the spinal cord, allowing quick responses without involving the brain.
24) Which part of the brain is responsible for regulating body temperature?
(a) Cerebrum
(b) Cerebellum
(c) Hypothalamus
(d) Medulla oblongata
Answer: (c) Hypothalamus
Explanation: The hypothalamus plays a key role in maintaining homeostasis, including regulating body temperature.
25) What is the primary function of cytokinins in plants?
(a) Cell division
(b) Fruit ripening
(c) Water regulation
(d) Inhibition of growth
Answer: (a) Cell division
Explanation: Cytokinins promote cell division and are essential for plant growth and development.
26) What type of nerves carry signals from the brain to muscles?
(a) Sensory nerves
(b) Motor nerves
(c) Mixed nerves
(d) Cranial nerves
Answer: (b) Motor nerves
Explanation: Motor nerves transmit signals from the brain and spinal cord to muscles to initiate movement.
27) Which hormone is responsible for the growth of root tips in plants?
(a) Gibberellin
(b) Auxin
(c) Cytokinin
(d) Abscisic acid
Answer: (b) Auxin
Explanation: Auxins accumulate in the root tips and promote cell elongation, aiding in root growth.
28) Which plant movement is a response to touch?
(a) Phototropism
(b) Geotropism
(c) Thigmotropism
(d) Chemotropism
Answer: (c) Thigmotropism
Explanation: Thigmotropism is the directional movement of plants in response to touch, seen in climbing plants like tendrils.
29) Which system in humans is responsible for chemical coordination?
(a) Nervous system
(b) Endocrine system
(c) Excretory system
(d) Digestive system
Answer: (b) Endocrine system
Explanation: The endocrine system secretes hormones that regulate various physiological processes in the body.
30) Which plant hormone inhibits growth?
(a) Gibberellin
(b) Auxin
(c) Cytokinin
(d) Abscisic acid
Answer: (d) Abscisic acid
Explanation: Abscisic acid inhibits growth and plays a role in dormancy and stress responses in plants.
31) What is the function of adrenaline in the human body?
(a) Regulates sleep patterns
(b) Controls metabolism
(c) Prepares the body for a ‘fight or flight’ response
(d) Regulates calcium levels
Answer: (c) Prepares the body for a ‘fight or flight’ response
Explanation: Adrenaline increases heart rate and energy supply to prepare the body for emergency situations.
32) Which type of neurons connect sensory and motor neurons?
(a) Sensory neurons
(b) Interneurons
(c) Motor neurons
(d) Reflex neurons
Answer: (b) Interneurons
Explanation: Interneurons relay signals between sensory and motor neurons in the central nervous system.
33) Which hormone controls the functions of other endocrine glands?
(a) Insulin
(b) Growth hormone
(c) Pituitary hormones
(d) Thyroxine
Answer: (c) Pituitary hormones
Explanation: The pituitary gland secretes hormones that regulate the activities of other endocrine glands.
34) What is hydrotropism in plants?
(a) Movement towards light
(b) Movement towards water
(c) Movement towards gravity
(d) Movement towards chemicals
Answer: (b) Movement towards water
Explanation: Hydrotropism is the growth of plant roots towards a water source.
35) Which part of the human brain regulates hunger and thirst?
(a) Cerebrum
(b) Cerebellum
(c) Hypothalamus
(d) Medulla oblongata
Answer: (c) Hypothalamus
Explanation: The hypothalamus regulates homeostatic functions such as hunger, thirst, and body temperature.
36) What is the role of insulin in the human body?
(a) Increase blood sugar levels
(b) Regulate blood pressure
(c) Decrease blood sugar levels
(d) Aid in digestion
Answer: (c) Decrease blood sugar levels
Explanation: Insulin helps lower blood sugar levels by promoting the uptake of glucose into cells.
37) Which gland produces thyroxine?
(a) Pituitary gland
(b) Adrenal gland
(c) Thyroid gland
(d) Pancreas
Answer: (c) Thyroid gland
Explanation: The thyroid gland secretes thyroxine, which regulates the body’s metabolism.
38) What is chemotropism in plants?
(a) Growth towards water
(b) Growth towards light
(c) Growth towards chemicals
(d) Growth towards touch
Answer: (c) Growth towards chemicals
Explanation: Chemotropism refers to the movement of plants in response to a chemical stimulus, such as pollen tube growth towards ovules.
39) What does the autonomic nervous system control?
(a) Voluntary actions
(b) Involuntary actions
(c) Sensory perception
(d) Memory and learning
Answer: (b) Involuntary actions
Explanation: The autonomic nervous system regulates involuntary functions such as heartbeat, digestion, and breathing.
40) Which hormone regulates the sleep-wake cycle?
(a) Melatonin
(b) Adrenaline
(c) Thyroxine
(d) Insulin
Answer: (a) Melatonin
Explanation: Melatonin, secreted by the pineal gland, controls the body’s biological clock, including the sleep-wake cycle.
41) Which hormone is responsible for the elongation of stems in plants?
(a) Auxin
(b) Cytokinin
(c) Gibberellin
(d) Ethylene
Answer: (c) Gibberellin
Explanation: Gibberellin promotes stem elongation, seed germination, and flowering in plants.
42) Which part of the nervous system includes the brain and spinal cord?
(a) Peripheral nervous system
(b) Central nervous system
(c) Autonomic nervous system
(d) Somatic nervous system
Answer: (b) Central nervous system
Explanation: The central nervous system (CNS) consists of the brain and spinal cord, coordinating the body's activities.
43) What is the effect of abscisic acid on plant growth?
(a) Promotes cell division
(b) Inhibits growth
(c) Enhances flowering
(d) Stimulates root growth
Answer: (b) Inhibits growth
Explanation: Abscisic acid inhibits plant growth and promotes dormancy, helping plants survive in stressful conditions.
44) What is the role of myelin sheath in neurons?
(a) Produces neurotransmitters
(b) Speeds up nerve impulse transmission
(c) Stores energy for the neuron
(d) Connects neurons to muscles
Answer: (b) Speeds up nerve impulse transmission
Explanation: The myelin sheath insulates axons and increases the speed of electrical signal transmission in neurons.
45) Which of the following is a plant response to gravity?
(a) Phototropism
(b) Geotropism
(c) Chemotropism
(d) Thigmotropism
Answer: (b) Geotropism
Explanation: Geotropism is the directional growth of plant parts in response to gravity, such as roots growing downward.
46) Which part of the brain controls emotions and drives like hunger?
(a) Cerebrum
(b) Cerebellum
(c) Hypothalamus
(d) Medulla oblongata
Answer: (c) Hypothalamus
Explanation: The hypothalamus regulates emotions, hunger, thirst, and other homeostatic functions.
47) Which of the following is a characteristic of reflex actions?
(a) Voluntary and conscious
(b) Quick and automatic
(c) Always involve the brain
(d) Slow and deliberate
Answer: (b) Quick and automatic
Explanation: Reflex actions are involuntary and rapid responses to stimuli, bypassing conscious brain activity.
48) What is the role of the stomata in plants?
(a) Absorb nutrients from the soil
(b) Facilitate gas exchange and transpiration
(c) Transport food throughout the plant
(d) Store energy
Answer: (b) Facilitate gas exchange and transpiration
Explanation: Stomata are tiny pores on the leaf surface that allow for gas exchange and water vapor release during transpiration.
49) What are neurotransmitters?
(a) Hormones secreted by the endocrine system
(b) Chemicals that transmit signals across synapses
(c) Proteins that protect neurons
(d) Nerve fibers that connect neurons
Answer: (b) Chemicals that transmit signals across synapses
Explanation: Neurotransmitters are chemical messengers that carry signals across synapses from one neuron to another.
50) Which part of the human body is responsible for regulating involuntary actions like digestion and respiration?
(a) Spinal cord
(b) Cerebrum
(c) Medulla oblongata
(d) Cerebellum
Answer: (c) Medulla oblongata
Explanation: The medulla oblongata controls involuntary actions such as digestion, heartbeat, and breathing.
51) Which plant hormone is known to delay aging in leaves?
(a) Cytokinin
(b) Auxin
(c) Gibberellin
(d) Abscisic acid
Answer: (a) Cytokinin
Explanation: Cytokinins delay aging by promoting cell division and chlorophyll retention in leaves.
52) What is the function of sensory receptors in animals?
(a) Detect environmental stimuli
(b) Store sensory information
(c) Produce hormones
(d) Control reflex actions
Answer: (a) Detect environmental stimuli
Explanation: Sensory receptors detect changes in the environment, such as light, sound, or temperature.
53) What is the primary function of the adrenal glands?
(a) Regulate metabolism
(b) Produce stress hormones like adrenaline
(c) Maintain blood sugar levels
(d) Aid in digestion
Answer: (b) Produce stress hormones like adrenaline
Explanation: The adrenal glands secrete adrenaline and cortisol, which prepare the body to respond to stress.
54) What happens during a reflex action?
(a) The brain processes the stimulus
(b) The response occurs without brain involvement
(c) Hormones control the response
(d) Conscious thought is required
Answer: (b) The response occurs without brain involvement
Explanation: Reflex actions bypass the brain and are processed by the spinal cord for quick responses.
55) Which part of the neuron receives signals from other neurons?
(a) Axon
(b) Dendrites
(c) Synapse
(d) Myelin sheath
Answer: (b) Dendrites
Explanation: Dendrites are the branching structures of a neuron that receive signals from other neurons.
56) Which hormone is responsible for root development in plants?
(a) Auxin
(b) Cytokinin
(c) Gibberellin
(d) Ethylene
Answer: (a) Auxin
Explanation: Auxins promote root development by enhancing cell elongation and division in root tips.
57) What triggers a reflex action?
(a) Hormonal changes
(b) External or internal stimuli
(c) Brain signals
(d) Muscle contractions
Answer: (b) External or internal stimuli
Explanation: Reflex actions are initiated by stimuli such as heat, pain, or touch.
58) Which gland secretes melatonin?
(a) Thyroid gland
(b) Pituitary gland
(c) Pineal gland
(d) Adrenal gland
Answer: (c) Pineal gland
Explanation: The pineal gland produces melatonin, which regulates sleep-wake cycles.
59) Which structure in neurons speeds up the transmission of nerve impulses?
(a) Axon terminals
(b) Myelin sheath
(c) Dendrites
(d) Synapses
Answer: (b) Myelin sheath
Explanation: The myelin sheath acts as an insulating layer, allowing nerve impulses to travel faster along the axon.
60) What is the function of ethylene in plants?
(a) Delays ripening
(b) Promotes ripening and leaf fall
(c) Inhibits seed germination
(d) Enhances cell elongation
Answer: (b) Promotes ripening and leaf fall
Explanation: Ethylene is a plant hormone that stimulates fruit ripening and leaf abscission.
MCQs from the Exercise part of the Chapter
1) Which of the following is a plant hormone?
(a) Insulin
(b) Thyroxine
(c) Oestrogen
(d) Cytokinin
Answer: (d) Cytokinin
Explanation: Cytokinin is a plant hormone that promotes cell division and is essential for plant growth and development. The other options, such as insulin and thyroxine, are hormones found in animals.
2) The gap between two neurons is called a:
(a) Dendrite
(b) Synapse
(c) Axon
(d) Impulse
Answer: (b) Synapse
Explanation: A synapse is the small gap between two neurons where nerve impulses are transmitted through chemical or electrical signals.
3) The brain is responsible for:
(a) Thinking
(b) Regulating the heartbeat
(c) Balancing the body
(d) All of the above
Answer: (d) All of the above
Explanation: The brain performs various functions, including cognitive processes (thinking), controlling involuntary actions like heartbeat regulation, and maintaining balance through the cerebellum.
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