Brainscape's Knowledge GenomeTM

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


See full index

Biological Systems > Chapter 27 Reproduction of flowering plants > Flashcards

Chapter 27 Reproduction of flowering plants Flashcards

1
Q

How do most angiosperms reproduce?

A

Sexually - leads to genetic diversity

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

How does sexual reproduction in angiosperms differ to vertebrate animals?

A

Meiosis - spores then Mitosis - gametes
Plants = alternation of generations
In plants, cells that will form gametes develop in adult organism

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

What are the 4 concentric groups of organs in a flower

A

Sepals
Petals
Carpels
Stamens

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

What are carpels?

A

Female sex organs

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

What are stamens?

A

Male sex organs

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

What are the 7 cells most female gametophytes consist of?

A

1 egg cell
2 synergids (attract pollen tube and remove sperm)
3 antipodal cells (degenerate)
1 central cell with 2 polar nuclei

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

What is the role of the 2 cells in a male gametophyte/

A

Double fertilization

1 fertilizes egg
Other haploid nuclei of female gametophyte to form triploid cell (gives rise to endosperm that nourishes embryo during early development)

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

How are wind pollinated plants adapted?

A

they have sticky, featherlke stigmas and produce a large number of pollen grains

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

How is selfing prevented by monoecious species?

A

physical separation of male and female flower or maturaton at different times

Some are genetically self-incompatable

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

What controls self incompatability?

A

cluster of linked genes in the S locus

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

What are integuments

A

tissue layers that surround megasporangium and develop into seed coat

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

What part of the flower becomes the fruit?

A

ovary

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

How do seeds prepare for dormancy?

A

Lose 95% of water

- protective proteins keep seed in viscous state

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

What are the functions of fruit?

A
  • protect seed from damage by animals and infection by microbial pathogens
  • Aid in seed dispersal
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the different methods of fruit dispersal?

A

Wind
Attached to animals
Disperesed by water
Swallowed by animals then deposited far away

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

What does flowering represent?

A

reallocation of energy from vegetative growth to reproductive growth

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

What are the 3 types of plants according to their lifespan?

A

Annual - complete life in a year
Biennial - take 2 years, vegetative growth in first year then reproductive growth in the second
Perennials - live 3 or more years, and typically flower every year

18
Q

What happens to the shoot apical meristem during reproductive growth?

A

Becomes an inflorescence meristem when it produces floral parts

Floral meristem - only produces a single flower

19
Q

What have scientists been studying in arabidopsis?

A

Genes that determine transition to flowering

  • Meristem identity genes
  • Gloral organ identity genes
20
Q

What do Meirstem identity genes do?

A

LEAFY and APETALAI initiate cascade of gene expression

21
Q

What do floral identity genes do?

A

produce transcription fctors that determine whether cells in the floral meristem will be sepals, petals, stamen or carpels

22
Q

What external cues initiate genes for floewring?

A
  • Photoperiod

- Temperature

23
Q

What is the difference between short day plants and long day plants?

A

SDPs - flower when day is shorter than critical maximum

LDPs - flower when longer than critical minimum

24
Q

WHat is the significance of photoperiodic control of flowering?

A

Local population flowers at the same time which promotes coss-pollination

25
What has experiments shown regarding the length of night and plant flowering?
It is the length of darkness, not light that triggers flowering Pft converted to Pr at night, SDP flower when ratio of Pft to Pr is low, LDPs when ratio i shigh
26
Where are phytochrome located? What does this mean for flowering signal?
In leaf | Signal must travel. Is diffusable protein florigen
27
What are the features of florigen
Protein that triggers flowering - Small and can pass though plasmodesmata - Diffuses to shoot apical meristem and combines with another protein to stimulate transcription of genes that initiate flowering
28
What genes are involved in flowering?
FT (Flowering locus T) codes for florigen CO (Constans) codes for transcription factor that activates synthesis of FT FD (Flowering locus D) codes for transcription factor that binds to FT in shoot apical meristem
29
How does temperature affect flowering?
Some plants require period of cool temperature (Vernalization) - Inhibit synthesis of FLC protein which inhibits expression of FD and FT
30
How are gibberellins involved in flowering?
activate meristem identity gene LEAFY which promotes transition to flowering
31
What is another mechnism that triggeres flowering (not environmental)?
Position of bud - determined by concentration gradient of substance along apical-basal axis - Inhibitor of FT-FD pathway from root has lower concentration in stem
32
What are the disadvantages of asexual reproduction?
no genetic diversity except from mutations
33
What are the advantages of asexual reproduction?
- parent always pass on advantageous allele combinations - avoid cost of producing flowers - avoid potential risky process of cross-pollination and seed germination
34
How does vegetative reproduction occur
Modification of vegetative organs - bamboo have underground rhizomes that produce new plants - Garlic bulbs are modified stems that can produce new plants
35
What sort of environment to plants that reproduce vegetatively usually live in
Unstable (e.g.e eroding hillsides) where germination is unreliable - Common in desserts
36
What is Apomixis?
asexual reproduction of seeds - results in clones
37
What are the mechanisms of apomixis?
Megasporocyte does not undergo meiosis - results in diploid cell that becomes embryo and seed - Diploid cells from integument form a diploid embryo sac which becomes an embryo and seed
38
What is grafting?
attaching a bud or piece of stem from one plant to a root bearing stem of another plant
39
What is the stock and scion of grafted plants?
Stock - root bearing part | Scion - grafted part
40
What is meristem culture
piece of shoot apical meristem cultured on growth media | - then planted in a field
41
What is meristem culture used for?
strawberries and potatoes and forestry

Biological Systems (20 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions