Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biology IB HL > 9.4 Plant Reproduction > Flashcards

9.4 Plant Reproduction Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

In what 3 ways can plants reproduce?

A

Vegetative propagation (asexual reproduction from a plant cutting)

Spore formations (e.g. moulds, ferns)

Pollen transfer (flowering plants – angiospermophytes)

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

What does sexual reproduction in flowering points involve?

A

Sexual reproduction in flowering plants involves the transfer of pollen (male gamete) to an ova (female gamete)

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

What 3 phases are involved in the sexual reproduction of flowering plants?

A

involves three distinct phases – pollination, fertilization and seed dispersal

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

What is pollination?

A

The transfer of pollen grains from an anther (male plant structure) to a stigma (female plant structure)

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

Can plants self-pollinate?

A

YES

Many plants possess both male and female structures (monoecious) and can potentially self-pollinate

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

Why do plants tend to not self-pollinate?

A

From an evolutionary perspective, cross-pollination is preferable as it improves genetic diversity

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

What is fertilisation?

A

Fusion of a male gamete nuclei with a female gamete nuclei to form a zygote

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

Where are the male and female gametes stored in a plant?

A

In plants, the male gamete is stored in the pollen grain and the female gamete is found in the ovule

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

What is seed dispersal?

A

Fertilisation of gametes results in the formation of a seed, which moves away from the parental plant

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

Why is seed dispersal useful?

A

This seed dispersal reduces competition for resources between the germinating seed and the parental plant

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

What varieties of seed dispersal are there?

A

There are a variety of seed dispersal mechanisms, including wind, water, fruits and animals

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

Will seed structures be the same for different methods of seed dispersal?

A

NO

Seed structure will vary depending on the mechanism of dispersal employed by the plant

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

What does cross-pollination involve?

A

Cross-pollination involves transferring pollen grains from one plant to the ovule of a different plant

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

In what ways can pollen be transfered?

A

Pollen can be transferred by wind or water, but is commonly transferred by animals (called pollinators)

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

What type of relationship do plants have with pollinators?

A

Pollinators are involved in a mutualistic relationship with the flowering plant – whereby both species benefit from the interaction

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

How do plants benefit from pollination?

A

The flowering plant gains a means of sexual reproduction (via the transference of pollen between plants)

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

How do pollinators benefit from pollination?

A

The animal gains a source of nutrition (plants secrete a sugar-rich substance called nectar to attract pollinators

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are common example of pollinators?

A

Common examples of pollinators include birds, bats and insects (including bees and butterflies)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How may a plant structurally adapt for birds (as pollinators)?

A

Flowers may be structured to optimise access for certain pollinators (e.g. tube-shaped flowers for birds with long beaks)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How may a plant structurally adapt for birds (as pollinators)?

A

Flowers may be structured to optimise access for certain pollinators (e.g. tube-shaped flowers for birds with long beaks)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are flowers?

A

Flowers are the reproductive organs of angiospermophytes (flowering plants) and develop from the shoot apex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What causes the enlargement of shoot apical meristems?

A

Changes in gene expression trigger the enlargement of the shoot apical meristem

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What does the tissue do in the shoot apical meristem?

A

This tissue then differentiates to form the different flower structures – sepals, petals, stamen and pistil

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is the activation of genes responsible for flowering influenced by? (basic)

A

abiotic factors - typically linked to seasons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

When will flowering plants most likely bloom?

A

Flowering plants will typically come into bloom when a suitable pollinator is most abundant - this is dependent on seasons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is the most common trigger for a change in gene expression?

A

The most common trigger for a change in gene expression is day/night length (photoperiodism)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Do flowers always contain both male and female structures?

A

NO

Most flowers possess both male and female structures (monoecious), but some may only possess one structure (dioecious)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is the male part of the flower called?

A

stamen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is the stamen composed of?

A

anther

filament

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What is the anther?

A

pollen producing organ of the flower

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is the male gamete of a flowering plant?

A

pollen is the male gamete of a flowering plant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What is the filament?

A

slender stalk supporting the anther (makes the anther accessible to pollinators)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What is the female part of the flower called?

A

pistil/carpel

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What is the carpel composed of?

A
  • stigma
  • style
  • ovule & ovary
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What is the stigma?

A

the sticky, receptive tip of the carpel that is responsible for catching the pollen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What is the style?

A

the tube-shaped connection between the stigma and ovule (it elevates the stigma to help catch pollen)

37
Q

What is the ovule?

A

the structure that contains the female reproductive cells

38
Q

What happens to the ovule after fertilisation?

A

after fertilisation, it will develop into a seed

39
Q

What 3 support structures do flowers possess?

A
  • petals
  • sepal
  • peduncle
40
Q

What are the petals?

A

brightly coloured modified leaves, which function to attract pollinators

41
Q

What is the sepal?

A

Outer covering which protects the flower when in bud

42
Q

What is the peduncle?

A

The stalk of the flower

43
Q

What is the purpose of flowering?

A

The purpose of flowering is to enable the plant to sexually reproduce via pollination, fertilisation and seed dispersal

44
Q

What 2 types of flowering plants are there? (depending on when they bloom)

A

Some plants bloom in long day conditions (summer), whereas other plants bloom in short day conditions (autumn / winter)

45
Q

What is the critical factor responsible for flowering?

A

The critical factor responsible for flowering is the length of light and dark periods, which is detected by phytochromes

46
Q

What are phytochromes?

A

Phytochromes are leaf pigments which are used by the plant to detect periods of light and darkness

47
Q

What is photoperiodism?

A

Phytochromes are leaf pigments which are used by the plant to detect periods of light and darkness

48
Q

What are the 2 forms of phytochromes?

A

Pr -inactive form

Pfr - active form

49
Q

When is the inactive form of phytochrome converted?

A

The inactive form of phytochrome (Pr) is converted into the active form when it absorbs red light (~660 nm)

50
Q

When is the active form of phytochrome broken down?

A

The active form of phytochrome (Pfr) is broken down into the inactive form when it absorbs far red light (~725 nm)

51
Q

Can the active form of phytochrome be converted into the inactive form?

A

YES

the active form will gradually revert to the inactive form in the absence of light (darkness reversion)

52
Q

Which form of phytochrome is predominant during the day? Why?

A

Because sunlight contains more red light than moonlight, the active form is predominant during the day

53
Q

Which form of phytochrome is predominant during the night? Why?

A

as the active form is reverted in darkness, the inactive form is predominant during the night

54
Q

How can plants be classified into long/short day plants?

A

Plants can be classed as short-day or long-day plants, however the critical factor in determining their activity is NIGHT LENGTH

55
Q

When do short-day plants flower? (length…)

A

Short-day plants flower when the days are short – hence require the night period to exceed a critical length

56
Q

How does phytochrome play a role in short-day plants?

A

In short-day plants, Pfr INHIBITS flowering and hence flowering requires low levels of Pfr (i.e. resulting from long night

57
Q

When do long-day plants flower? (length…)

A

Long-day plants flower when the days are long – hence require the night period to be less than a critical length

58
Q

How does phytochrome play a role in long-day plants?

A

In long-day plants, Pfr activates flowering and hence flowering requires high levels of Pfr (i.e. resulting from short nights)

59
Q

How can horticulturalists manipulate flowering?

A

Horticulturalists can manipulate the flowering of short-day and long-day plants by controlling the exposure of light

60
Q

What must be uninterrupted/maintained to control plant flowering?

A

The critical night length required for a flowering response must be uninterrupted in order to be effective

61
Q

In what seasons will long-day plants typically not flower?

A

These plants will traditionally not flower during the winter and autumn months when night lengths are long

62
Q

How can horticulturalists manipulate long-day plants to bloom?

A

Horticulturalists can trigger flowering in these plants by exposing the plant to a light source during the night

63
Q

What is an example of a long-day plant?

A

Carnations are an example of a long-day plant

64
Q

When will short-day plants typically not flower?

A

These plants will traditionally not flower during the summer months when night lengths are short

65
Q

How can horticulturalists manipulate short-day plants to bloom?

A

Horticulturalists can trigger flowering in these plants by covering the plant with an opaque black cloth for ~12 hours a day

66
Q

What is an example of a short-day plant?

A

Crysanthemums are an example of a short-day plant

67
Q

In, for example, a greenhouse, what length of darkness do long-day plants require?

A

Long-day plants require periods of darkness to be less than an uninterrupted critical length

68
Q

In, for example, a greenhouse, what length of darkness do short-day plants require?

A

Short-day plants require periods of darkness to be greater than an uninterrupted critical length

69
Q

What does germination create?

A

The seed will be dispersed from the parental plant and will then germinate, giving rise to a new plant

70
Q

What 5 features does a typical seed possess?

A
  • testa
  • micropyle
  • cotyledon
  • plumule
  • radicle
71
Q

What is the testa?

A

an outer seed coat that protects the embryonic plant

72
Q

What is the micropyle?

A

a small pore in the outer covering of the seed, that allows for the passage of water

73
Q

What is the cotyledon?

A

contains the food stores for the seed and forms the embryonic leaves

74
Q

What is the plumule?

A

the embryonic shoot (also called the epicotyl)

75
Q

What is the radicle?

A

the embryonic root

76
Q

What is germination?

A

Germination is the process by which a seed emerges from a period of dormancy and begins to sprout

77
Q

What 4 basic factors does a seed require to germinate?

A
  • oxygen
  • water
  • temperature
  • pH
78
Q

Why does a seed require oxygen for germination?

A

or aerobic respiration (the seed requires large amounts of ATP in order to develop)

79
Q

Why does a seed require water for germination?

A

to metabolically activate the seed (triggers the synthesis of gibberellin)

80
Q

Why does a seed require temperature for germination?

A

seeds require certain temperature conditions in order to sprout (for optimal function of enzymes)

81
Q

Why does a seed require pH for germination?

A

seeds require a suitable soil pH in order to sprout (for optimal function of enzymes)

82
Q

Why might some plant species require fire as a condition for germination?

A

some seeds will only sprout after exposure to intense heat (e.g. after bushfires remove established flora)

83
Q

Why might some plant species require freezing as a condition for germination?

A

some seeds will only sprout after periods of intense cold (e.g. in spring, following the winter snows)

84
Q

Why might some plant species require digestion as a condition for germination?

A

some seeds require prior animal digestion to erode the seed coat before the seed will sprout

85
Q

Why might some plant species require washing as a condition for germination?

A

some seeds may be covered with inhibitors and will only sprout after being washed to remove the inhibitors

86
Q

Why might some plant species require scarification as a condition for germination?

A

seeds are more likely to germinate if the seed coat is weakened from physical damage

87
Q

How can experiments be developed to test germination?

A

Experiments can be developed using any of these factors as an independent variable

88
Q

How can germination be measured?

A

Germination can be measured by the rate of seed growth over a set period of time

Biology IB HL (56 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions