Sexual Reproduction in Flowering Plants

• Carpel

‣

Draw a diagram of a carpel

• Stamen

‣

Draw a diagram of the stamen

• Anther

• Diploid microspore mother cells

1. Diploid microspore mother cell divides by meiosis
2. This forms a group of 4 haploid cells known as a tetrad
3. This tetrad then breaks up forming 4 separate pollen grains
4. Each of these pollen grains divides by mitosis to produce two haploid nuclei

• 2 polar nuclei
• 1 egg cell

• Embryo sac

• Ovule

1. Diploid megaspore mother cell in the ovule divides by meiosis to form 4 haploid cells
2. Of these 4 haploid cells, 3 of them will degenerate (die off) and 1 will remain
3. This 1 remaining haploid cell is known as the embryo sac
4. This embryo sac will undergo mitosis 3 times
5. This forms a large embryo sac containing 8 haploid nucei
6. 5 of the 8 haploid nuclei die off
7. 2 of them become the polar nuclei
8. 1 of them becomes the egg cell

• By the tube nucleus

• The seed coat

• Protects the seed
• Helps seed with dispersal

• Protects the embyro

• Shoots

• Roots

• Food storage

1. Endospermic seeds contain endosperm when fully formed

1. Non-endospermic seeds do not contain endosperm when fully formed

2. Endospermic seeds store food in the endosperm

2. Non-endospermic seeds store food in the cotyledon

• Maize

• Broad bean

• 1

• 2

• Endosperm

• Cotyledon