bio的f.4的問題(ch16&15)

1)How can the shoot tip control the growth response at the zone of elongation ?
--Shoot tips produce auxins that stimulate the growth of plant, when there is light from one side, the auxins will move to the shaded side. As high concentration of auxins promote the growth of plants, the shaded side will grow faster, this is also called the zone of elongation.

2)In some patients, they cannot speak clearly after a stroke (中風) . Do you know which part of the brain is damaged ?
--As speaking is a voluntary action, the association area of the cerebrum is damaged.