plant tropisms

Question 1

what is the process of a stem growing towards the light called

Answer 1

positive phototropism

Question 2

what is the process of a stem growing away from the gravity called

Answer 2

negative gravitropism

Question 3

what controls phototropism and gravitropism

Answer 3

auxin

Question 4

how do auxin work in phototropism

Answer 4

auxin is produced at the tip and it speeds up cell growth

if the light is provided from all sides, auxin diffuses into all sides of the plant equally so the shoot grows straight upwards

if the light is only provided on one side, there will be more auxin in the dark side of the plant. cell with more auxin will absorb more water and grow more quickly. so the plant is bent toward the light source.

Question 5

how do auxin work in gravitropism

Answer 5

auxin slows down cell growth in roots

more auxin will be on the lower side to slow down the growth

less auxin will be on the upper side to speed up the growth

so the root grow downwards( towards gravity)