Control and Coordination — Class 10 Science PYQs

Human brain has various parts or regions that help in different actions, responses and coordination. From the following, identify the part responsible for precision of voluntary actions :

Assertion (A) : Reflex actions do not involve thinking.
Reason (R) : Most reflex actions are controlled by the spinal cord.

(a) State two differences between the act of chewing food and salivation on sight of food.
OR
(b) State two differences between pollination and fertilization.

Give differences between the following :
(a) Nephron and neuron
(b) Sensory nerve and motor nerve
(c) Consumers and decomposers

The plant hormone whose concentration stimulates the cells to grow longer on the side of the shoot which is away from light is :

Plants have neither a nervous system nor muscles, even then they respond to stimuli. For example, the leaves of chhui-mui (touch-me-not) plant when touched begin to fold up and droop.
(a) How is the information communicated in "touch-me-not" plants ?
(b) What enables the plant cells to bring out the observable response ?
(c) Differentiate the movement mentioned above from the movement of tendrils in a pea plant.

(a) Name the glands that secrete :
(i) Adrenaline
(ii) Thyroxin
(b) Explain with example how the timing and amount of hormone released are regulated in the human body.

A hormone 'X' is secreted in blood when a person is under scary situation.
(a) Identify the hormone 'X' and the gland that secretes it.
(b) Explain its role in dealing with scary or emergency situations.

Observe the given figures A and B. When chhui-mui (sensitive) plant is touched, its leaves fold. This is due to :

Name the parts of hind-brain of the human brain. Which part of the hind-brain controls involuntary actions such as blood pressure and salivation ?