UNIT 2: TOPIC 3Plant Reproduction and Breeding

What is selective breeding? Choosing specific plants with particular

characteristics and encouraging those plants to reproduce

Plants are also bred to withstand environmental conditions such as:

Hardiness Yield Resistance to disease How well it stores

Heather, Calluna vulgaris, one of Britain's hardiest plants

Genes

Genetic material in a plant

Genetically Modified Plants Scientists combine genetic material from

two different plants, so it has genes from both.

Plant Reproduction

Asexual reproduction happens when a “parent” plant grows new plants from its foots, stems, or leaves.

Vegetative Reproduction

When young plants are identical to the parents- usually happens when a new plant grows from the root of another. Can also occur through stems

Grafting

To take a branch from one tree and attach it to another

http://www.youtube.com/watch?v=XpgbpbewU3E

Seed Plant ReproductionFemale Cone Male Cone

-Contains ovules-Catches pollen grains, and once the pollen tube grows down to the ovule, pollination occurs

-Smaller-Pollen grains develop on it

http://studyjams.scholastic.com/studyjams/jams/science/plants/flowers.htm

1. Parts of a Flower

2. Pollination Occurs when

pollen has been transferred from the anther to the stigma. When the pollen grain germinates on the stigma it creates a burrow called the pollen tube as it travels toward the ovary

http://www.youtube.com/watch?v=wDM8OtS5MPM

3.

When the pollen grain reaches the ovule, fertilization occurs

4.

Pollination must take place before fertilization can take place

5.

The fertilized embryo will become a tiny new plant inside the seed

Pollination

Two types of pollination are self-pollination and cross- pollination

2 ways of cross-pollination

1. Wind 2. Animals

Artificial Pollination

When plant breeders breed plants for specific purposes

Once a plant has been pollinated, a seed is formed! Inside the seed is a tiny plant that is called an embryo. It is protected by a seed coat that helps it stay alive or dormant.

What conditions does a seed need to be able to grow?

Sunlight Water Air

When you bite into a pear you are eating a fruit! What is the function of fruit for a plant?

A fruit is the growing ovary of the plant that swells and protects the developing seeds of a plant until they are ripe.

Name 5 ways that seeds are spread

1. Wind

2. Water (ex. Coconut)

3. Eaten by animals

4. “Hitch a ride” on animals

5. Fire

Farmers use machines to spread seeds like wheat, canola, barley.

Germination

The development of a seed into a new plant.

http://studyjams.scholastic.com/studyjams/jams/science/plants/flowers.htm