PPEs revision Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

What is the function of the auxin?

A

Control growth at the tips of the shoots and the roots.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What do the auxins do?

A

They dissolve in the solutions of the cell. They then diffuse backwards along the shoots and the roots.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What does auxins do at the roots?

A

Inhibit growth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What does auxins do at the shoots?

A

Stimulate growth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is it called when a plant responds to light?

A

Phototropism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is it called when a plant responds to gravity?

A

Geotropism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What side will the auxins accumulate?

A

They will either go on the shaded side or the lower side.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the shoots positively and negatively?

A

They positively phototropic and negatively gravitropic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What does it mean to be positively phototropic?

A

Grow towards the light

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What does it mean to be positively gravitropic?

A

Grow towards the gravity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the roots positively and negatively?

A

They are negatively phototropic and negatively gravitropic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What causes plants to grow towards the light?

A

Auxins accumulate on the shaded side. Therefore the cells on the shaded sides grow faster which causes the plant to bend to the light.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What causes the roots to curve downwards?

A

If exposed to light the auxins will accumulate on the lower shaded side and in the roots auxins inhibit growth which t hem causes the upper side to grow faster

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the 3 uses of auxins?

A
  • To grow plant clones
  • To grow plant cuttings
  • To kill weeds
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How does auxins kill plants?

A

By adding a lot of auxins it can disrupt the plants growth patterns

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are 3 uses of gibberellin?

A
  • Controlling dormancy
  • Inducing Flowering
  • Grow larger fruits
17
Q

How does gibberellin control dormancy?

A

Induces germination at certain times of the year when plants dont have the right conditions to grow

18
Q

How does gibberellin induce flowering?

A

Flowers need certain conditions to grow but gibberellin allows flowers to grow on demand which can allow farmers to grow bigger and more flowers

19
Q

How does gibberellin help growing larger fruits?

A

It is useful for seedless fruits that naturally dont grow as seeded fruits. Gibberellin allows the fruits to grow well.

20
Q

What is the used of the hormone ethene for plants?

A

Stimulate the ripening of fruits by stimulating a hormone.

21
Q

What 3 factors affect diffusion?

A

Distance, concentration difference and surface area

22
Q

rate of diffusion is proportional to…

A

surface area x concentration difference / thickness of membrane

23
Q

What happens if the surface area or the difference in concentration doubles?

A

The rate of diffusion will double

24
Q

What happens if the thickness of membrane halves?

A

The rate of diffusion will half

25
Q

What is thermoregulation used for?

A

To control our internal body temperature

26
Q

Which part of the brain controls thermoregulation?

A

Hypothalamus

27
Q

What mechanisms does the body use to warm us up?

A
  • The blood vessels that lie on the surface of the skin constrict to decrease the amount of blood that flows near the surface. This then decreases the amount of heat energy lost
  • Contraction of erector muscles to trap a small layer of insulating air
  • We shiver which is caused by the muscles contracting automatically
28
Q

What mechanisms does the body use to cool us down?

A
  • Erector muscles relax causing the hairs to fall flat
  • The blood vessels expand to allow more heat energy to transfer to the surroundings as it is closer to the skin surface
  • We produce sweat which is a mixture of water and salt so when it evaporates it takes heat energy away from the skin