Lesson 3.2Seeds develop from the fertilized ovule.

Fruits develop from the ripening ovary.

Lesson 3.2

Fruit provides protection and dispersal for seeds.

Fruits include acorns, grains of wheat, tomatoes, and what we think of as fruits (oranges, apples, etc.)

ANY RIPENED OVARY IS A FRUIT!!!

POLLINATION

-IS THE TRANSFER OF POLLEN FROM THE ANTHER TO THE STIGMA OF THE PISTIL.

POLLINATION

Two types of pollination:

1.Self pollination •pollination that occurs within the same flower or anotherflower on the same plant.

POLLINATION

Two types of pollination:

2. Cross pollination •when pollen comes from the anther of one plant to the stigma of a different plant.

•Aided by birds, insects, wind, rain and horticulturalist.

Factors affecting pollination:

1.nectar – sweet substance to attract insects and birds (bees and humming birds)

Factors affecting pollination:1. Nectar

2. colorful flowers and fragrances

ex. Carrion plant produces a flower that smells like raw meat and is red like raw meat. It attracts flies to help with pollination.

Carrion plant

Factors affecting pollination:1. Nectar

2. Colorful flowers and fragrances

3.Creator DesignOr How a flower and insect are designed by the Creator.

Ex. Yucca flower is only pollinatedby the Yucca moth that can reach the pollen.

Horticulturalist •specialize in growing plants •artificially cross pollinate different species to produce HYBRIDS.•Hybrids – a combination

ex. Seedless watermelons

Fertilization – the joining of the sperm cell (male gamete) with the egg cell (female gamete).

Gamete = reproductive cell

Pollen has traveled and landed on stigma. (pollination)

Steps of fertilization:

1. Pollen tube is formed and grows down to the ovule.

2. Sperm cell divides forming two sperm cells.

1.

2.

Steps of fertilization:

3. Sperm cells travel down the pollen tube to the ovule.

4. One sperm cell unites with egg cell in the ovule.

5. The other sperm cell triggers the production of endosperm.

4.

Sexual Reproduction: requires the union of the male and female gametes resulting in the exchange of genetic information.

Asexual reproduction:•Formation of new individuals from a single parent cell•No genetic information is exchanged •No fertilization

Formation of Ripening FruitWhen ovule is fertilized a seed is produced.

Seed triggers the release of hormone in the plant that tells the fruit to ripen.

Formation of Ripening Fruit

Some plants have fruits without seeds such as the banana.Banana treereproduces asexually from

rhizome (under ground stem)

Fruits are prepared for picking by the formation of the abscission layer where the fruit attaches to the branch.

Formation of Ripening Fruit

Fruits are prepared for picking by the formation of the abscission layer where the fruit attaches to the branch.

Pollen and People

Pollen breathed into respiratory system by people can cause an allergic reaction

called HAYFEVER.

Pollen and People

Pollen triggers the body to release a chemical messenger called histamine which causes an allergic reaction in the body.

People taken an antihistamine to block the production of the histamine.

Pollen and People

The pollen index is based on amount of ragweed pollen in the air.