Topic 6b - Plant repro. & dev. Flashcards Preview

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Flashcards in Topic 6b - Plant repro. & dev. Deck (23):
1

Re. alternation of generations...diploid mother cells develop from which structures? (male/female)?

Anthers (male)
Ovaries (female)

2

Re. alternation of generations...meiosis of mother cells in sporophyte produces...?

haploid spores

3

Re. alternation of generations...male (pollen) & female gametophytes produce...?

sperm & eggs

4

Go thru slide 5...

kill me now!

5

What structures make up the stamen?

anther & filament

6

What structures make up the carpel?

stigma, style, ovary

7

1st step in fertilisation of flower...When does pollination occur?

when pollen grain lands on the stigma of a carpel...see slide 13

8

2nd step in fertilisation of flower...What happens after pollination occurs?

pollen tube grows down thru style of carpel, tube cell nucleus & sperm follow...see slide 13

9

3rd step in fertilisation of flower...Double fertilisation...

pollen tube & sperm reach female gametophyte - one sperm fuses with central cell, the other sperm fuses with egg cell...see slide 13

10

Fruit develops from the ...?

ovary

11

Seeds develop from the ...?

ovule

12

What are the 6 major groups of plant hormones?

auxins
gibberellins
cytokinins
ethylene
absidic acid
florigens

13

Charateristics of auxins...

promotes cell elongation in shoots
inhibits cell elongation in roots
stim. fruit dev.

14

Charateristics of gibberellins...

promotes stem elongation
stimulates - bud sprouting, flowering, fruit prod., seed germination...

15

Charateristics of cytokinins...

promote cell division
inhibits lateral root branch formation
stimulates lateral shoot branch formation
nutrient transport -> leaves

16

Charateristics of ethylene...

in most plant tissue
stress hormone
ripening of fruit

17

Charateristics of absidic acid...

throughout plant
helps with adaptive responses

18

Charateristics of florigens...

timing of flowering
identified in 2005

19

Which 2 plant hormones work together?

auxins & cytokinins

20

What is photoperiodism? What agent is responsible? 3 types...

changes in flowering of a plant in response to changes in day length
agent - phytochrome (2 forms)
- no change
- long-day
- short-day

21

What is the important variable in photoperiodism?

duration of uninterrupted darkness (not day length per se)

22

2 forms of phytochrome?

Pr - absorbs light in red wavelengths
Pfr - absorbs light in far red wavelengths

23

Phytochrome control of flowering in short day (long night) plants?

Pfr (inhibits flowering) gets converted -> Pr thus low Pfr -> removal of inhibition of flowering -> initiation of flowering