Fill in the following blanks:

(a) A plant's response to light is called .................

(b) A plant's response to gravity is called .................

(c) Plant shoot grow upward in response to ..............

(d) Plant roots grow downward in response to .............

(e) Tendrils wind around a support in response to ..........

(f) Plant roots grow towards .......... and in the direction of force of ...............

(g) A root of a plant grows downward. This is known as ..............

(h) ........... is the hormone that causes phototropism in plants

(i) The response of leaves to the sunlight is called ..............