Plant Reproduction

Question 1

Speals

Answer 1

Protect flowering bud

Question 2

Petals

Answer 2

Attract insects for pollination

Question 3

Stames

Answer 3

Produce more pollen

Question 4

Carpels

Answer 4

Produce female embryo sac

Question 5

Pollen development

Answer 5

Diploid(2n) micros pore mother cells divide by meiosis to form 4 haploid cells
Each haploid forms a pollen grain
Nucleus of the pollen grain divides by mitosis to form a tube nucleus and a generative nucleus

Question 6

Embryo sac development

Answer 6

Single diploid megaspore mother cell divides by meiosis to form 4 haploid cells
3 degenerate and 1 divides by mitosis 3 times
Cell with its nuclei is known as the embryo sac

Question 7

Pollination

Answer 7

Transfer of pollen grain from an anther to a stigma of a flower of the same species

Question 8

Types of pollination

Answer 8

Self pollination: uses its own pollen

Cross pollination:uses pollen from another plant (insect/animal and wind)

Question 9

Fertilisation

Answer 9

The fusion of two haploid gametes to form a diploid zygote

Question 10

Stages of fertilisation

Answer 10

Pollen grain germinates and the generative nucleus divides by mitosis to produce 2 male gamete nuclei
Tube nucleus grows down through the style (chemotropism)
2 male gamete nuclei enter the embryo sac and double fertilisation occurs:
-1st male gamete+female egg=zygote
-2nd male gamete+2 polar nuclei=triploid endospermic nucleus

Question 11

Seed formation

Answer 11

Fertilised ovule becomes the seed

Question 12

Food stores

Answer 12

Cotyledon

Endosperm

Question 13

Fate of zygote after fertilisation

Answer 13

Develops to form embryo

Question 14

Fate of endosperm nucleus after fertilisation

Answer 14

Develops to form endosperm food store

Question 15

Fruits are formed from

Answer 15

Ovary

Question 16

Methods of seed dispersal

Answer 16

Wind
Animal
Water
Self

Question 17

Germination

Answer 17

Regrow the of the embryo after a period of dormancy, if conditions are suitable

Question 18

Conditions necessary for germination

Answer 18

Water
Air
Suitable temperature

Question 19

Process of germination

Answer 19

Seed absorbs water
Enzymes digest the food stores ie. Starch is turned to glucose
Radicle grows and bursts through the testa
Plumule emerges above ground
Stem and leaves develop

Question 20

Dormancy

Answer 20

Resting period where seeds undergo no growth and have reduced metabolic activity

Question 21

Advantages of dormancy

Answer 21

Allows plants to avoid the harsh conditions of winter
Gives embryo time to fully develop
Allows maximum growing time

Question 22

Vegetative propagation

Answer 22

Asexual reproduction in flowering plants

Question 23

Natural vegetative propagation

Answer 23

Stem-potato
Root-raspberry
Bud:onion

Question 24

Artificial vegetative propagation

Answer 24

Cutting

Layering

Question 25

Differences between sexual and asexual reproduction

Answer 25

Sexual-genetic variation

Asexual-increased competition

Question 26

Advantages of seed dispersal

Answer 26

Colonisation

Reduces competition

Question 27

Radicle

Answer 27

Develops root

Question 28

Plumule

Answer 28

Develops shoot

Question 29

Why dry mass is preferred in germination

Answer 29

Water content could vary between seeds