chap. 30 : plant reproduction i.plant reproductive parts a. mosses and ferns : antheridium (male)...

Chap. 30 : Plant Reproduction

I. Plant Reproductive Parts

A. mosses and ferns : antheridium (male) and archegonium (female)

B. gymnosperms (conifers and ginkgo) : microspores (male) and megaspores (female)

C. angiosperms : flowering plants

1. Flower Parts

pollen

Male parts :1. Anther2. Pollen-sperm3. Stamen

Female parts :4. Stigma5. Pistil6. Ovary (eggs)

2. Pollen Formation

stigma

anther

stamen

Anther holds 4 pollen sacs each containing many microspores.

Makes 4 pollen grains, each with 2 sperm

3.Ovule (egg) formation

ovary

The ovum is the egg and is enlarged from absorbing all the divisions of the megaspores.

At the end of ovule formation there is an egg and 2 polar nuclei

4. Pollination – transfer of pollen from anther to stigma

Done by : wind, water, insects, birds, animals

5. Fertilization : Steps 1. Pollen gets on stigma forming a pollen

tube

2. Pollen tube connects stigma to embryo sac

3. 2 sperm travel to embryo sac

4. 1 sperm fertilizes egg to make zygote while other unites with polar nuclei to make endosperm (food for embryo) or (fruit for animals)

5. After fertilization the flower withers and drops off