plant reproduction

Question 1

what is the male part of a flowering plant

Answer 1

Stamen

Question 2

what makes up the stamen

Answer 2

Anther

filament

Question 3

what is the female part of a flowering plant

Answer 3

Carpel

Question 4

what makes up the carpel

Answer 4

stigma
style
ovary

Question 5

what protects the growing bud

Answer 5

sepal

Question 6

what are all the sepals collectively grouped as

Answer 6

Calyx

Question 7

what is the function of the petals

Answer 7

insect pollinated

• brigthly coloured to attract insects
• pushes downwards under the insects’ weight making the stigma/style jerk upwards to hit the insect/dust it with pollen

Question 8

what are all the petals collectively grouped as

Answer 8

Corolla

Question 9

Explain gametogenesis of the ovum

Answer 9

megaspore mother cell nucleus divides by meiosis. 3 cells degenerate. 1 cell that remains expands

cell left divides by mitosis 3 times to form 8 haploid nuclei (within one cell).

3 nuclei at each pole, 2 in the middle

cell walls form around nuclei it poles

two nuclei in the middle = polar nucleus
middle cell near micropyle= egg cell

Question 10

explain how the pollen grain forms

Answer 10

pollen mother cell divides by meiosis to form 4 pollen cells

haploid nucleus in pollen grain divides by mitosis- forms tube nucleus and generative (male) nucleus

Question 11

what is dehisence

Answer 11

process by which anther splits down the middle lengthways to release mature pollen grains

Question 12

what is the role of the tapetum

Answer 12

layer of cells in anther

provide nutrition for the growing pollen grain

Question 13

how self pollination avoided

Answer 13

protandry
protogeny
dioecious species

Question 14

what is protandry

Answer 14

maturation of male parts before female

Question 15

what is protogeny

Answer 15

maturation of female parts before male

Question 16

what is a dioecious species

Answer 16

a species with wither male or female flowers

Question 17

what is the difference between wind pollinated and insect pollinated plants

Answer 17

wind pollinated

• lots of small flowers, densely populated
• small petals
• no nectar
• large quantities of light, smooth aerodynamic pollen
• feathery, sticky, branched stigma-net effect
• reproductive organs (stamen and stigma) outside the flower

insect pollinated

• fewer larger flowers, in small groups
• large colourful, scented flowers
• produce nectar
• smaller number of large, sticky, irregular pollen grains
• sticky stamen
• shorter anthers, reproductive organs inside flower

Question 18

explain fertilisation from pollination

Answer 18

pollen grain lands on stigma of compatible flower
pollen tube nucleus releases hydrolytic enzymes that digest down style
(pollination)

male nucleus follows behind.
male nucleus divides by mitosis- forms 2 male haploid nuclei
pollen tube enters embryo sac via micropyle
tube nucleus disintegrates

1 male nucleus fuses with egg cell
1 male nucleus fuses with diploid polar nucleus

Question 19

what does the fertilised egg cell become

Answer 19

embryo

radical, plumule

Question 20

what does the ovule develop into

Answer 20

seed

Question 21

what does the triploid nucleus develop into

Answer 21

endosperm

food source for growing seed

Question 22

what do the ovary walls develop into

Answer 22

fruit

Question 23

what conditions does a seed need to become a plant

Answer 23

water
oxgen
suitable temp

Question 24

how does germination happen

Answer 24

water taken into the seed (imbition)
this causes the testa to rupture- allows oxygen in for respiration
in endospermic seeds gibberellins are released which induce hydrolytic enzymes in aleurone layer to break down proteins so new enzymes can be made to break down carbohydrates etc

radical grows down
plumule grows up
plumule bent to protect growing bud