Coordination and response [Plants] Flashcards
1
Q
State the conditions in which pots P and Q were kept
A
Pot P: (uniform) light
pot Q: no light/dark
2
Q
State the name of the growth response shown by the seedlings in pot R.
A
phototropism
3
Q
Explain the advantage to the seedlings of this growth response
A
- more (light) energy absorbed
- more photosynthesis
- more growth
4
Q
Explain how auxins control the growth response of the seedlings in pot R
A
- (auxins) produced in tip
- diffuses down the stem
- auxins collect in the side
- greater (cell) elongation on side in the dark
5
Q
State the name of the response of plants to light
A
phototropism
6
Q
Describe an experiment he could carry out to show that auxin causes bending of a shoot
A
- paint auxin on one side of shoot
- place shoot in a dark place
- leave for period of time (e.g. 1 to 3 days)
- until the shoot grows vertically
7
Q
Explain the mechanism that results in a shoot bending towards light
A
- auxin is broken down by light
- difference in concentrations on shaded side and light side
- cells with higher concentration of auxin absorb more water causing to unequal growth
8
Q
Synthetic plant hormones behave in a similar way to auxins. Describe how synthetic plant hormones are effective as weedkillers
A
- stems are stimulated to grow rapidly
- Growth gets out of control
