CBSE Class 10 Science Control and Coordination VBQs

Question. Cytokinins are known to:
(a) inhibit cytoplasmic movement
(b) help in retention of chlorophyll
(c) influence water movement
(d) promote abscission layer formation
Answer : B

Question. Which part of the human brain is most well-developed?
(a) Forebrain
(b) Hindbrain
(c) Diencephalon
(d) None of these
Answer : A

Question. The box enclosing the brain is called the _____________.
(a) Skull
(b) Head
(c) Cranium
(d) vertebral column
Answer : C

Question. In reflex action, the reflex arc is formed by
(a) Muscles - receptor – brain
(b) Muscles - effector – brain
(c) Receptor - spinal cord – muscles
(d) Spinal cord - receptor – muscles
Answer : C

Question. The plant hormone which is essential for cell division is
(a) Ethylene
(b) Auxin
(c) Gibberellin
(d) Cytokinin
Answer : D

Question. _______ are also known as ductless gland
(a) Salivary gland
(b) Endocrine gland
(c) Exocrine gland
(d) Both B & C
Answer : B

Question. Electrical impulse travels in neuron from:
(a) Dendrite→axon→axon end→cell body
(b) Cell body→Dendrite→axon→axon end
(c) Dendrite→cell body→axon→axon end
(d) Axon end→axon→cell body→Dendrite
Answer : C

Question. Cerebellum is situated in ___________.
(a) fore brain
(b) mid brain
(c) hind brain
(d) partly in A and B each
Answer : C

Question. The substance that accelerates the growth in the stem is ____.
(a) auxin
(b) cytokinin
(c) enzyme
(d) vitamin
Answer : A

Question. The endocrine gland also known master glands ______.
(a) hypothalamus
(b) pituitary
(c) pancreas
(d) adrenal
Answer : B

Question. The gap between two neurons is known as ___.
(a) synapse
(b) synopsis
(c) impulse
(d) synaptic node
Answer : A

Question. Growth hormone is produced in ___________.
(a) hypothalamus
(b) pituitary
(c) pancreas
(d) thyroid
Answer : B

Question. An action potential traveling along an axon:
(a) moves rapidly in both directions.
(b) moves faster than a neurotransmitter.
(c) is slowed by myelin.
(d) travels through the blood.
Answer : B

Question. Which part of the human brain controls body temperature?
(a) Pituitary
(b) Diencephalon
(c) Hypothalamus
(d) None of these
Answer : C

Question. Which of the following comments applies to the brains of most animals?
(a) Within the brain, neurons exchange information with one another.
(b) Brains usually lie as near as possible to the important sensory structures in an animal.
(c) Brains send action potentials to the hindmost portion of the animal by means of major nerves.
(d) All of the above
Answer : D

Question. In comparison with other cells, nerve cells show a higher degree of:
(a) Metabolism
(b) Growth
(c) Contractility
(d) Irritability
Answer : D

Question. Coordination via the nervous system tends to differ from that produced by the endocrine system because the nervous system:
(a) is quick, precise and localized
(b) is slower and more pervasive
(c) does not require conscious activity
(d) has long-lasting effects
Answer : A

Question. The photoreceptor cells of the eye are located in the:
(a) Sclera
(b) Iris
(c) Retina
(d) Optic nerve
Answer : C

Question. Which of the following acts both as Endocrine
(ductless) and Exocrine (with duct) gland?
(a) pancreas
(b) liver
(c) adrenal
(d) kidney
Answer : A

Question. Female sex hormone is termed as
(a) androgen
(b) insulin
(c) oestrogen
(d) None of these
Answer : C

Question. Autonomic nervous system control:
(a) reflex action
(b) sense organs
(c) internal organs
(d) skeletal muscle
Answer : C

Question. Which of the following receptors is incorrectly paired with what is senses?
(a) Chemoreceptors-chemicals
(b) Photoreceptors-pain
(c) Thermoreceptors-heat
(d) Nociceptors-pain
Answer : B

Question. In reflex action, the reflex arc is formed by:
(a) brain → spinal cord → muscles
(b) receptor → spinal cord → muscles
(c) muscles → receptor → brain
(d) muscles → spinal cord → receptor
Answer : B

Fill in The Blank

Question. The hormone which controls the development of male secondary sexual character is called .......... .
Answer : estosterone

Question. Coordination in plants take place by means of chemical substance called .......... .
Answer : phytohormone

Question. Touch me not shows .......... movement.
Answer : nastic

Question. Receptors are structures which are able to detect .......... .
Answer : stimuli

Question. The functional junction between two neurons is called .......... .
Answer : synapse

Question. Short day plants come to flower .......... a critical photoperiod.
Answer : Below

Question. Endocrine glands secrete their secretion in .......... .
Answer : blood

Question. Human growth hormone regulates the many body processes involved in ......... and ...........
Answer : growth, development

Question. A .......... mechanism regulates the action of hormones.
Answer : feed back

Question. Neurons that carry information to an effector are called .......... neurons.
Answer : motor

Question. Hormones are carried by .......... to target organs where they perform a specific function.
Answer : blood stream

Question. Temporal lobe of cerebrum is region for .......... reception.
Answer : auditory

True/False

Question. Motor neurons carry signals from receptors to spinal cord.
Answer : False

Question. All animals have complex nervous systems.
Answer : False

Question. Feeling hunger is a reflex action.
Answer : False

Question. Involuntary actions like salivation, vomiting, blood pressure are controlled by the medulla in the hind brain.
Answer : True

Question. Photoperiodism was first studied by Garner and Allard.
Answer : True

Question. The human brain is the largest of all animals.
Answer : False

Question. Brains can work 24 hours a day with no rest.
Answer : False

Question. Thyroxine regulatres the blood-sugar.
Answer : False

Question. Immediate response to stimulus is shown as Mimosa pudica.
Answer : True

Question. Sensory neurons carry signals from spinal cord to muscles.
Answer : False

Question. The path through which signals are transmitted from a receptor to a muscle or a gland is called reflex arc.
Answer : True

Question. Sugarcane is short day plant.
Answer : True

Question. Portions of your brain are responsible for specific functions.
Answer : True

Question. Fore-brain is centre of intelligence, control of movements, hearing, smell and sight.
Answer : True

Question. Apical dominance is the function of Auxin.
Answer : True

Question. Spinal cord originates from Cerebellum.
Answer : False

Assertion and Reason

DIRECTION : In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
(a) Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
(b) Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
(c) Assertion (A) is true but reason (R) is false.
(d) Assertion (A) is false but reason (R) is true.
(e) Both Assertion and Reason are false.

Question. Assertion : Olfactory receptors detect taste.
Reason : Olfactory receptors are present in cerebellum.
Answer : E

Question. Assertion : Animals can react to stimuli in different ways.
Reason : All animals have a nervous system and an endocrine system involving hormones.
Answer : A

Question. Assertion : Medulla oblongata causes reflex actions like vomiting, coughing and sneezing.
Reason : It has many nerve cells which control autonomic reflexes.
Answer : A

Question. Assertion : In short day plant, day length should be less than critical day length.
Reason : Long night should be continuous.
Answer : B

Question. Assertion : Cytokinins are present in highest concentration in fruits and seeds.
Reason : Cytokinins are responsible for promoting cell division.
Answer : B

Question. Assertion : Seismonastic movement shown by Mimosa pudica plant.
Reason : It is due to change in turgidity of cells of pulvinus.
Answer : A

Question. Assertion : Units which make up the nervous system are called neurons.
Reason : Nerve impulses are carried by dendrites towards the cell body.
Answer : B

Question. Assertion : Gibberellins induce internodal growth in dwarf plant varieties.
Reason : Gibberellins when applied to normal plants, it increases the length of the plant.
Answer : C

Question. Assertion : Our body maintains blood sugar level.
Reason : Pancreas secretes insulin which helps to regualte blood sugar levels in the body.
Answer : A

Question. Assertion : Plant hormones arc growth regulator.
Reason : Growth regulators promote or inhibit the growth.
Answer : A

Very Short Questions Answer

Question. A person suffered a head injury, due to which he faces breathing problem. No problem was detected with his respiratory system. What could be the cause of this problem? 
Answer : As the problem is caused due to head injury, it could be related to “Pons” a part of Hind brain responsible for regulation of respiration.

Question. A man becomes unconscious due to head injury. A pin is pricked on his foot, he withdraws his foot. Why? Explain. 
Answer : It is reflex action. Stimulus is perceived by receptor (skin). Sensory nerve sends the sensation from receptor to the spinal cord. Then spinal cord sends the message through motor nerves to the effectors. Effectors i.e. muscles help in withdrawing his foot.

Question.In a family of normal sized members, there are two exceptions, one member is dwarf and one is tall like “Khali”. What could be the cause of it? 
Answer : In case of dwarfs, there is a deficiency of growth hormone from Pituitary gland and in case of giants excess of growth hormone is produced during childhood.

Question. Why do you blink your eyes as bright light is focused on you? 
Answer : We blink in order to protect the eye from bright light which otherwise would damage the retina.

Question. There is a potted plant in your drawing room, after few days you note that plant has bent to one side. What could be the reason? How has this movement been co- coordinated?
Answer : The plant has bent to one side due to phototropic movement of the stem. This movement is due to unequal growth of the stem on both sides. This growth is initiated by the hormone auxin.

Question. A leaf shaped gland is present above the intestine. The secretion of this gland regulates the metabolism of sugar in blood. Name the secretion and gland. 
Answer : The name of the gland is pancreas. The secretion is Insulin from special cells in it.

Question. How is the spinal cord protected in the human body?
Answer : Spinal cord is enclosed in a bony cage called vertebral column.

Question. Mention the function of adrenaline hormone.
Answer : Adrenaline hormone is released into the blood from the adrenal gland during stimulation of the nervous system on seeing any adverse situation of fight or fright, it increases the blood pressure, it increases heart beat rate, it increases breathing rate and it diverts blood to essential organs including the heart, brain and skeletal muscles by dilating their blood vessels and constricting those of less essential organs, such as the skin and digestive system.

Question. A potted plant is made to lie horizontally on the ground. Which part of the plant will show
(i) positive geotropism?
(ii) negative geotropism?
Answer : (i) Root (ii) Shoot.

Question. A young green plant receives sunlight from one direction only. What will happen to its shoots ?
Answer : Shoots will bend towards the light and roots away from the light.

Question. Give one example of chemotropism.
Answer : The growth of pollen tube towards a chemical produced by ovule during fertilisation of flower is an example of chemotropism.

Question. What is the function of thyroxine hormone in our body ?
Answer : Thyroxine hormone regulates the carbohydrate, protein and fat metabolism in the body so as to provide the best growth balance.

Question. Which one of the following actions on touch is an example of chemical control?
(i) Movement on the touch-sensitive plant.
(ii) Movement in human leg.
Answer : (i) Movement on the touch-sensitive plant.

Question. Name the two components of central nervous systems in humans.
Answer : The two components of Central Nervous System in human are brain and spinal cord.

Question. Mention the part of the body where gustatory and olfactory receptors are located.
Answer : Gustatory receptors are located in Cerebrum of fore-brain. Olfactory receptors are located in Olfactory lobe of fore-brain.

Question. Name the plant hormones which help/promote (i) cell division (ii) growth of the stem and roots?
Answer : The plant hormones which help or promote:
(i) Cell division — Cytokinins
ii) Growth of the stem — Gibberellins

Question. State the function of:
(i) gustatory receptors, and
(ii) olfactory receptors.
Answer : (i) Gustatory receptors – these are sensitive to taste
(ii) Olfactory receptors – these are sensitive to smell.

Question. Name the fluid that is found between the meninges.
Answer : Cerebrospinal fluid

Question. State how concentration of auxin stimulates the cells to grow longer on the side of the shoot which is away from light ?
Answer : When light falls on the side of the shoot auxin diffuses towards the shady side of the shoot. This concentration of the auxin stimulates the cell to grow longer on the side of the shoot which is away from light. Thus plant appears to bend towards light.

Question. Name two tissues that provide control and coordination in multicellular animals.
Answer : The two tissues that provide control and coordination in multicellular animals are nervous and muscular tissues.

Question. Give an example of a plant hormone that promotes its growth. Where it is synthesized ?
Answer : Plant hormone that promotes growth is auxin. It is synthesized at the tip of the plant stem.

Question. Mention the function of the hind-brain in humans.
Answer : Hind brain controls respiration, cardio-vascular reflexes and gastric secretions.
It also modulates the motor commands initiated by the cerebrum.

Question. Name the part of the brain which controls posture and balance of the body.
Answer : Cerebellum in hind-brain controls the posture and balance of the body.

Question. What is the significance of reflex action?
Answer : Reflex action enables the animal to respond quickly and relieves the brain from excess work.

Question. Why is it advised to use iodised salt in our diet ?
Answer : Iodine stimulates the thyroid gland to produce thyroxin hormone. Deficiency of this hormone results in the enlargement of the thyroid gland. This can lead to goitre.

Question. Where are Nissl’s granules found and what is their nature?
Answer : Nissl’s granules are found in cyton and dendrites. These are formed of ribonucleic acid (RNA).

Short Answer Type Questions

Question. Name, the two main organs of our central nervous system. Which one of them plays a major role in sending command to muscles to act without involving thinking process? Name the phenomenon involved.
Answer : The two main organs of CNS are brain and spinal cord. Spinal cord plays a major role in sending command to muscles to act without involving thinking process. This phenomenon is called reflex action.

Question. Which organ secretes a hormone when bloo’d sugar rises in our body? Name the hormone and name one enzyme released by this organ.
Answer : Pancreas secretes a hormone when blood sugar rises in our body. Insulin is the hormone released by this organ and the name of the enzyme is pancreatic juice.

Question. Name and explain the function of the hormone secreted by the pituitary gland in humans.
Answer : Hormones secreted by pituitary gland alongwith their functions are:
• Growth hormone: It regulates growth and development ofbones and muscles.
• Trophic hormone: It regulates secretion of hormones from other endocrine glands.
• Prolactin hormone: It regulates the function of mammary glands in females.
• Vasopressin hormone: It regulates water and electrolyte balance in the body,
• Oxytocin hormone : It regulates ejection of milk during lactation.

Question. (i) Name the hormones that are released in human males and females when they reach puberty.
(ii) Name a gland associated with brain. Which problem is caused due to the deficiency of the hormone released by this gland ?
Answer : (i) Testes in males produces hormone testosterone.
Ovaries in females produces hormone oestrogen.
(ii) Pituitary gland present in the brain is responsible for body growth, development of bones and muscles (if excess-gigantism) (if less-dwarfism) 

Question. Write the name and functions of any two parts of the human hind-brain.
Answer : Any two parts of human hind-brain with their functions are as follows:
(i) Cerebellum, which controls the coordination ofbody movement and posture. (ii) Medulla oblongata, which regulates the centre of swallowing, coughing, sneezing and vomiting.

Question. What is synapse ? In a neuron cell how is an electrical impulse created and what is the role of synapse in this context ?
Answer :A synapse is the gap between the two neurons. Here the axon terminal of one neuron is in close proximity to the dendrite of the second neuron. When a nerve impulse reaches the knob like nerve ending of an axon, a tiny amount of a chemical substance is released in the synapse. This chemical substance is called as the neurotransmitter. At synapse the electrical signals converted into chemicals, that can easily cross over the gap and pass on to the next neurons where it again converted into electrical signals.

Question. Distinguish between cerebrum and spinal cord.
Answer :

Question. What are plant hormones? Write two important functions of auxin.
Answer : Plant hormones can be defined as a chemical substance which is produced naturally in plants and are capable of translocation and regulating one or more physiological processes when present in low concentration. .
Two important functions of auxin are that it promotes cell elongation, root formation, cell division, etc.

Question. Distinguish between sympathetic and parasympathetic nervous system.
Answer :

Question. What are ‘nastic’ and ‘curvature’ movements? Give one example of each.
Answer : Nastic movements: These are non-directional movements which are neither towards nor away from the stimulus. Example: Dropping of leaves. Curvature movements: In such movements plant organs move towards or away from the stimulus.
Example: Bending of shoot towards a source of light.

Question. (a) Which plant hormone is present in greater concentration in the areas of rapid cell division?
(b) Give one example of a plant growth promoter and a plant growth inhibitor.
Answer : (a) Cytokinin is present in greater concentration in the areas of rapid cell division.
(b) An example of a plant growth promoter is gibberellins and example of a plant growth inhibitor is abscisic acid.

Question. Write the difference between cerebellum and cerebrum.
Answer :

Question. Name the hormone secreted by human testes. State its functions.
Answer : Testes secrete male sex hormone called testosterone. The function of testosterone is to regulate male accessory sex organs and secondary sexual characters like moustache, beard and voice.

Question. Distinguish between spinal nerve and cranial nerve.
Answer :

Question. How does control and coordination take place in plants ?
Answer : In plants, control and coordination is brought about by means of chemical substances called phytohormones. In addition, environmental factors like water, temperature and light, controls growth and development.