B1g Flashcards
1
Q
what processes do plant hormones control?
A
- the growth of shoots towards light
- growth of roots downwards so they can find water
- growth of flowers
- ripening of fruit
2
Q
what is phototropism?
A
when a plant responds to light
3
Q
what is geotropism?
A
when a plant responds to gravity
4
Q
what is synthetic auxin?
A
it is sprayed onto crops to kill weeds. the hormone makes the weeds grow too fast and they die. this is called a selective weedkiller.
5
Q
how does auxin make the plant grow?
A
- auxin is made in the tip of the plant
- auxin moves away from light and collects on the shaded side of the shoot
- auxin causes cells on shaded side to elongate more than cells on the other side.
- the shaded side becomes longer and causes the shoot to bend.
