Biotechnology Bell Ringersfor October 19th, 2010

1. How many organisms are required for asexual reproduction in plants?

2. What is the difference between rhizomes and runners?

3. What is cell and tissue culture?

Biotechnology Objectivesfor October 19th, 2010

We will talk about sexual reproduction in plants

We will examine the life cycle of “Fast plants”

Time permitting, we will talk about some current events in Biotechnology

Sexual Reproduction inFlowering Plants

What is Sexual Reproduction?

Sexual reproduction in plants is when a new individual is produced by combining materials from two parents

Sexual Reproduction in Plants

In plants, a sperm moves towards an egg

Fertilization occurs when the egg and sperm nuclei unite to start development of the offspring

By repeated cell division, the fertilized egg grows from a single cell into a many-celled embryo that develops into a seed

Sexual Reproduction in Plants

All living things that reproduce sexually take some features from each parent

Next year’s flowers will resemble this year’s flowers because they inherit features from both of their parents

Sexual Reproduction in Plants

The flower is the structure that makes sexual reproduction in flowering plants possible

A wide variety exists in flower appearance, but the function of the flower parts is the same

The Parts of a Flower

Most flowers have four parts1. Sepals2. Petals3. Stamens4. Carpels

The Parts of a Flower

The sepal protects the bud until it opens

Parts of a Flower

The petals attract insects

Some plants have no petals

Parts of a Flower

The stamen contains the male part of the flower

It produces pollen

Parts of a Flower

The carpels (ovaries) grow into fruits which contain the seeds

Stamen (Male)

The stamen produces pollen, a yellow powdery substance

Pollen is produced in the top of the stamen, in a structure called the anther

When the pollen grains are fully grown, the anther splits open

Pistil (Female)

The top of the pistil is called the stigma

When a pollen grain reaches the pistil, it sticks to the surface of the stigma

The stigma produces sugar that is used by pollen to grow a pollen tube inside the style

Pistil (Female)

The pollen tube inside the style allows delivery of the sperm down to the ovary

The ovary (carpel) is the enlarged part of the pistil where the female sex cells (eggs) are produced

The eggs (ovules) are fertilized by sperm from the style

Pollination

The transfer of the pollen from anther to the stigma is called pollination

Flowering plants use the wind, insects, bats, birds, and mammals to transfer pollen

Fertilization

Pollen grains germinate on the stigma, growing down the style to reach an ovule

Fertilized ovules develop into seeds

The carpel enlarges to form the flesh of the fruit and to protect the ovary

Seed Dispersal

Seeds are dispersed in many different ways:› Wind› Explosion› Water› Animals› Birds› Scatter

Wind Dispersal

Explosion Dispersal

Water Dispersal

Animal Dispersal

Bird Dispersal