Solved the very best collection of Control and Coordination Class 10 Science Important Questions and Answers Chapter 7 Pdf from the latest NCERT edition books, It will help you in scoring more marks in CBSE Exams.
Control and Coordination Class 10 Important Questions with Answers Science Chapter 7
Control and Coordination Class 10 Important Questions Very Short Answer Type
Question 1.
Name the largest cell in the human body. (CBSE 2008)
Answer:
Nerve cell.
Question 2.
Name the part of the brain which controls posture and balance of the body. (CBSE 2012)
Answer:
Cerebellum in hind-brain controls the posture and balance of the body.
Question 3.
Mention the part of the body where gustatory and olfactory receptors are located. (CBSE 2012)
Answer:
Gustatory receptors are located in Cerebrum of fore-brain. Olfactory receptors are located in Olfactory lobe of fore-brain.
Question 4.
Smita’s father has been advised by a doctor to reduce his sugar intake.
- Name the disease he is suffering from and name the hormone whose deficiency is?
- Identify the gland that secretes it and mention the function of this hormone.
- Explain how the time and amount of secretion of this hormone is regulated in human system. (CBSE 2012)
Answer:
- Disease is diabetes, Hormone is insulin.
- Pancreas secretes it and it helps in regulating the blood sugar level.
- When the sugar level in blood increases, it is detected by the a-cells of the pancreas which responds by producing more insulin. As the blood sugar level falls, insulin secretion is reduced.
Question 5.
(a) How is brain protected from injury and shock?
(b) Name two main parts of hind brain and state the functions of each. (CBSE 2012)
Answer:
(a) Brain is covered by a three layered membrane called meninges. In between the layers of meninges and brain, cavity fluid named Cerebro Spinal Fluid (CSF) is filled. The hard skull covers the meninges. Thus Meninges, CSF and Skull protects our brain for a certain extent.
(b) Two main parts of hind-brain are – Medulla and Cerebellum. Their functions are:
- Medulla: Involuntary actions such as blood pressure, salivation and vomiting.
- Cerebellum: It is responsible for precision of voluntary actions and maintaining the posture and balance of the body.
Question 6.
(a) Draw the structure of neuron and label cell body and axon.
(b) Name the part of neuron:
(i) Where information is acquired.
(ii) Through which information travels as an electrical impulse. (CBSE 2012)
Answer:
(a) A nerve cell (Neuron)
(b) (i) Dendrite
(ii) Axon.
Question 7.
(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. (CBSE 2012)
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 8.
State the function of:
(i) gustatory receptors, and
(ii) olfactory receptors. (CBSE 2013)
Answer:
(i) Gustatory receptors – these are sensitive to taste
(ii) Olfactory receptors – these are sensitive to smell.
Question 9.
Give an example of a plant hormone that promotes its growth. Where it is synthesized. (CBSE 2014)
Answer:
Plant hormone that promotes growth is auxin. It is synthesized at the tip of the plant stem.
Question 10.
Why is it advised to use iodised salt in our diet? (CBSE 2015)
Answer:
The iodine is required for the functioning of the thyroid gland and the major source of iodine intake for our body is through the iodized salt the deficiency of which may lead to goiter.
Question 11.
State how concentration of auxin stimulates the cells to grow longer on the side of the shoot which is away from lingt? (CBSE 2015)
Answer:
When growing plants detect light, a hormone called auxin which is synthesized at
the shoot tip, helps the cells to grow longer/elongated. When light is coming from one side of the plant, the auxin diffuses towards the shady side of the shoot. This helps the cells to grow longer on the side of the shoot which is away from light in shady area. The helps plant to bend towards the light.
Question 12.
What is synapse? In a neuron cell how is an electrical impulse created and what is the role of synapse in this context? (CBSE 2015)
Answer:
The functional junction between the nerve ending of one neuron and the dendrite of the other is called synapse. It allows the transfer of message. The electrical impulse is created in the nerve cell due to the chemicals present in it like Na and K ions. Synapse helps in the transfer of the nerve impulse.
Control and Coordination Class 10 Important Questions Short Answer Type
Question 1.
Define ‘hormones’. Name the hormone secreted by thyroid. Write its function. Why is the use of iodised salt advisable to us? (CBSE 2008)
Answer:
Hormones are the chemicals released by endocrine glands which acts as messengers in control and coordination of the body.
Thyroid gland secretes thyroxine.
Function- It regulates the metabolism of carbohydrates, fats and proteins.
Iodised salt gives iodine to the body which is necessary for the thyroid gland to produce thyroxin.
Question 2.
What is the function of the hormone secreted by the endocrine gland, pituitary? (Foreign 2008)
Answer:
Pituitary gland secretes a growth hormone. It regulates the growth of the body.
Question 3.
Name the three major regions of the human brain. Which part of the brain maintains posture and equilibrium of the body? (Foreign 2008)
Answer:
Three major regions of human brain are fore brain, mid brain and hind brain. Cerebellum maintains the posture of the body.
Question 4.
Distinguish between voluntary and involuntary actions of our body. (Foreign 2008)
Answer:
- Voluntary actions are under the control of our will, it needs thinking e.g. talking, walking, etc.
- Involuntary actions are not under the control of our will, they are automatic eg. salivation, heart beat.
Question 5.
Why is the use of iodised salt advisable? (CBSE 2008)
Answer:
Iodine from the iodised salt is absorbed in our body which helps in the formation of thyroxin hormone secreted by thyroid gland.
Question 6.
Explain the cause of shoots of the plant bending towards light. (CBSE 2008)
Answer:
Shoot of the plant bends towards light due to phototropism. The stimulus is light and the movement of shoot is towards light.
Question 7.
“There is a need for a system of control and coordination in an organism”. Justify the statement. (CBSE 2008)
Answer:
Larger and complex organisms have specific organs for specific functions. All organs should function in perfect coordination. To facilitate this, there is a need for a system of control and coordination.
Question 8.
What are nastic and curvature movement? Give one example of each. (CBSE 2009)
Answer:
Nastic movement: It is a non-directional movement, e.g. touch me not plant drops it leaves on touching.
Curvature movement: It is a change in orientation of different parts of plant like bending, frosting, curling, e.g. curling of stem tendril.
Question 9.
Define reflex action. (CBSE 2009)
Answer:
It is a spontaneous, involuntary and unconscious response to a stimulus.
Question 10.
Define chemotropism. (CBSE 2009)
Answer:
When the stimulus is some chemical then movement due to response is called chemotropism.
Question 11.
What are hormones? State one function of each of the following hormone
(i) Thyroxin
(ii) Insulin. (AI 2009)
Answer:
Hormones are chemicals released by endocrine gland.
(i) Thyroxine helps in the metabolism of carbohydrates, proteins and fats.
(ii) Insulin helps in regulating sugar level in the blood.
Question 12.
Which one of the following actions on touch is an example of chemical control?
Movement of the touch-sensitive plant.
Movement in human leg. (Foreign 2009)
Answer:
Movement of the touch-sensitive plant.
Question 13.
What is reflex action? Describe the steps involved in a reflex action. (Foreign 2009)
Answer:
It is an unconscious automatic and involuntary response.
Steps involved in reflex action
- Receptors receive the stimulus.
- Nerve cell takes the stimulus, converts it into electrical signal and passes it through sensory nerve.
- The impulse passes through spinal cord where it gets transmitted through relay neuron and it passes further through motor neuron to the effector organ i.e., muscles.
Question 14.
(a) Explain any three directional movements in plants.
(b) How brain and spinal cord are protected in human?
(c) Name the master gland present in the brain. (CBSE 2013)
Answer:
(a) Geotropism: Movement of roots towards the earth.
Hydrotropism: Movement of roots towards water.
Phototropism: Movement of plant parts towards light
(b) Brain is protected by skull made up of bone and the spinal cord is protected by the bony vertebrae. They are further protected by the cushion layers inside and a fluid which absorbs shocks.
(c) The master gland in the brain is called pituitary gland.
Question 15.
(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? (CBSE 2014)
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 the release is in excess it causes gigantism and if it is produced less then it causes dwarfism.
Question 16.
Draw neat diagram of human brain and label on it the following parts:
(i) Midbrain
(ii) Pituitary gland (CBSE 2014)
Answer:
Question 17.
Write one example for each of the following tropic movements:
(i) Positive phototropism
(ii) Negative phototropism
(iii) Positive geotropism
(iv) Negative geotropism
(v) Hydrotropism
(vi) Chemotropism (CBSE 2014)
Answer:
(i) Positive phototropism: Shoots growing towards light.
(ii) Negative phototropism: Roots growing away from light towards ground.
(iii) Positive geotropism: Growth of roots towards^earth due to the pull of the earth, i.e. gravity.
(iv) Negative geotropism: Shoots growing away from gravity.
(v) Hydrotropism: Roots growing towards the source of water.
(vi) Chemotropism: Growth of pollen tubes towards the ovary.
Control and Coordination Class 10 Important Questions Long Answer Type
Question 1.
(a) Draw the structure of a neuron and label the following on it: Nucleus, Dendrite cell body and Axon.
(b) Name the part of neuron
(i) where information is
(ii) through which information travels as an electrical impulse. (AI 2008)
Answer:
(a)
(b) (i) Dendrite acquires information.
(ii) Electrical impulse travels through
Neuron- dendrite → cell body → axon → nerve ending
Question 2.
(a) What is (i) phototropism and (ii) geotropism? With labelled diagrams describe an activity to show that light and gravity change the direction that plants grow in.
(b) Mention the role of each of the following plant hormones:
(i) Auxin
(ii) Abscisic acid (AI 2008)
Answer:
(a) (i) Phototropism: Movement of plant in response to light.
(ii) Geotropism: The movement of plant (roots) towards the gravity.
Activity to show that light and gravity changes the direction of plant growth.
Phototropism: When a plant is kept in a box with one side of it open then the shoot of the plant tend to move out of the box towards the light while root moves and grows away from the light. See figure (a) on previous page.
Geotropism: When a plant pot is tilted and watered the root grows towards the gravity and shoot grows away from the gravity as shown in the figure (b) on previous page.
(b) (i) Auxin: It promotes the cell elongation, cell division, growth of tips of root and shoot.
(ii) Abscisic acid: It inhibits the growth, responsible for wilting of leaves.
Question 3.
In the given diagram of human brain label A and B and write their function. (CBSE 2008)
Answer:
A – Cerebellum-Maintain Posture and body balance.
B – Medulla-Involuntary action like blood pressure, salivation, vomiting are controlled by medulla.
Question 4.
Which animal or plant hormone is associated with the following:
(i) increased sugar level in blood
(ii) change at puberty in boys
(iii) inhibits growth of plants
(iv) rapid development of fruits
(v) dwarfism
(vi) goitre (CBSE 2008C)
Answer:
(i) Insulin
(ii) Testosterone
(iii) Abscisic acid
(v) Growth hormone
(vi) Thyroxin
Question 5.
(a)
(i) Name the parts labelled A and B in the neuron drawn above.
(ii) Which part acquires the information in the neuron?
(iii) Through which part does the information travel?
(iv) In what form does this information travel?
(v) Where is the impulse converted into a chemical signal for onward transmission?
(b) Name the hormone secreted by thyroid. What is its function? Why is the use of iodised salt advisable? (AI 2008)
Answer:
(a) (i) A – Dendrite, B – axon
(ii) Dendrite acquires the information
(iii) Cell body and axon
(iv) Electrical impulse
(v) Synapse.
(b) Thyroid secretes thyroxin.
Function – Controls the metabolism of carbohydrates, proteins and fats.
Iodised salt gives iodine to the body due to which thyroid can make thyroxin.
Question 6.
(a) What are plant hormones? Give one example each of a plant hormone that
(i) promotes growth
(ii) inhibits growth
(b) Names the parts labelled A, B and C in the diagram given below. Write one function of each part. (AI 2008)
Answer:
(a) The chemical substances produced by plants for the coordination of plant body is called plant hormone.
(i) Promotes growth-Auxin
(ii) Inhibits growth-Abscisic acid
(b) A-Pons-It regulates respiration
B-Medulla-It controls involuntary action.
C-Cerebellum-It controls posture and balance of the body.
Question 7.
What is phototropism? How does it occur in plants? Describe an activity to demonstrate phototropism. (AI 2009)
Answer:
Phototropism: The movement of plant towards the light is called phototropism.
Occurrence: The plants at its root tip consists of auxin which helps in the growth of a plant and the plant moves towards the light.
Question 8.
(a) Name the hormone which is released into the blood when its sugar level rises.
Explain the need of chemical communication in multicellular organisms the organ which produces this hormone and its effect on blood sugar level. Also mention the digestive enzymes secreted by this organ with one function of each.
(b) Explain the need of chemical communication in multicellular organisms. (CBSE 2014)
Answer:
(a) Our body needs glucose for cellular respiration and its concentration is always maintained. Insulin hormone produced by pancreas cells regulate the glucose level in the blood.
In multicellular organisms the cells must communicate for the proper functioning of the body. When needed pancreas produces insulin which can also increase the glucose level in the blood. It also prouduces digestive amylase enzyme.
(b) The communication of cells in multicellular organisms happen by cell to cell signaling. Through the communication between cell to cell the messages are carried from signaling cells to receiving cells, known as target cells.
This signaling occurs with the proteins and other types of signaling molecules. The growth and development, cellular reproduction, tissue repair, sensing pain etc., are possible due to this cell communication.
Question 9.
State the structural and the functional unit of the nervous system. Draw its neat labelled diagram and write two functions. (CBSE 2014)
Answer:
The structural and functional unit of the nervous system is called neuron.
Two functions of neuron:
- Neurons receive signals from a sense organ.
- Neurons send signals to a muscle or a gland.