Plant Hormones Flashcards

1
Q

What do hormones do?

A

Stimulate or inhibit activity.

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

What are growth regulators?

A

Man-made versions of hormones.

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

How do plant hormones bring about change?

A

By binding to receptors on plant cells which initiates biochemical signal transmissions.

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

What are biochemical signal transmissions?

A

Chemical reactions that bring about physiological changes.

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

Name some examples of plant hormones.

A

Auxins, gibberellins, cytokinins, abscisic acid, ethylene, brassinosteroids.

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

Who discovered auxins?

A

Frits Went.

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

What are auxins structurally similar to?

A

Tryptophan

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

What do we associate auxins with?

A

Phototropisms, fruit development, apical dominance

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

Where are auxins made?

A

Apical meristems, buds and in young leaves.

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

What are auxins?

A

Plant hormones that encourage the bending of plant tips towards the light.

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

What do auxins promote?

A

Flowering & fruiting

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

What do auxins inhibit?

A

Leaf abscission

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

What might auxins help regulate?

A

Cell elongation

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

What are gibberellins?

A

Plant hormones that stimulate growth.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Where are gibberellins made?

A

apical meristems, young leaves and in embryos

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

What are gibberellins involved in?

A

Cell elongation, mitosis stimulation in internodes, breaking dormancy, stem elongation and initiating flowering

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Where were cytokinins first discovered?

A

The phloem.

18
Q

What do cytokinins do?

A

They stimulate cell division, differentiation, cotyledon growth, lateral bud development and the production of cork cambium

19
Q

Where are cytokinins found?

A

Germinating seeds and roots

20
Q

What can cytokinins delay?

A

Senescence

21
Q

What can cytokinins encourage?

A

Stomatal opening

22
Q

What happens if the ratio between cytokinin and auxin is equal?

A

The plant will grow haphazardly.

23
Q

What happens if the ratio of cytokinin is higher than auxin?

A

Tissue develops in the shoots

24
Q

What happens if the ratio of cytokinin is lesser than auxin?

A

Tissue develops in the roots

25
Q

What does abscisic acid do?

A

Inhibits plant growth

26
Q

What does abscisic acid trigger?

A

Bud dormancy

27
Q

When was abscisic acid discovered?

A

1960s

28
Q

How is abscisic acid used?

A

It’s used in transport to prevent buds opening too early

29
Q

Where is abscisic acid made and found?

A

It’s made by plastids, and is found in drupe flesh.

30
Q

How does abscisic acid affect stomatal closing?

A

Leaves produce more abscisic acid when water is lacking, this influences the transport of potassium ions, which makes gurad cells more flaccid.

31
Q

What are brassinosteroids?

A

Plant steroid hormones

32
Q

Where are brassinosteroids found?

A

Reproductive organs and within growing tissues.

33
Q

What can brassinosteroids do?

A

Increase photosynthesis and resistance to disease and stress.

34
Q

What can brassinosteroids influence?

A

Cell elongation & division, pollen tube growth, seed germination and xylem differentiation.

35
Q

What can brassinosteroids inhibit?

A

lateral bud growth and leaf senescence

36
Q

What other hormone can brassinosteroids counteract?

A

Abscisic acid

37
Q

What does this imply about brassinosteroids?

A

That they can trigger flowering, seed germination and stomatal opening.

38
Q

What is ethylene?

A

A gas that can ripen fruit.

39
Q

Where is ethylene produced?

A

In fruits, flowers, roots, seeds and leaves,

40
Q

What else can ethylene trigger?

A

Leaf abscission, senescence, bud development and cell elongation.