What is the stimulus involved in the process of thigmotropism?

What does the central nervous system in humans consist of?

When a person is suffering from severe cold,he or she cannot :

Which hormone of the pituitary gland causes contraction of uterine muscles during childbirth and stimulates milk ejection from the mammary glands in females?

Which of the following is $NOT$ a control center located in the medulla oblongata?

Name the plant hormones responsible for the following:
$(a)$ Elongation of cells
$(b)$ Growth of stem
$(c)$ Promotion of cell division
$(d)$ Falling of senescent leaves.