Which of the following hormones requires iodine for its synthesis?

$(a)$ How are the movement of leaves of touch-me-not and the growth of a stem towards light different?
$(b)$ What is chemotropism? Give one example.
$(c)$ What is tropism?

$(a)$ Draw a diagram of the human brain.
$(b)$ Label the Cerebrum and Cerebellum on it.
$(c)$ What is the role of the Cerebellum?

$(a)$ An old man is advised by his doctor to take less sugar in his diet. Name the disease from which the man is suffering. Mention the hormone due to imbalance of which he is suffering from this disease. Which endocrine gland secretes this hormone?
$(b)$ Name the endocrine gland which secretes growth hormone. What will be its effect on a person of:
$(i)$ Deficiency of growth hormones?
$(ii)$ Excess secretion of growth hormones?

The cerebellum,medulla,and pons are parts of which of the following?

What is the correct direction of flow of electrical impulses?