5.4 Asexual Reproduction

Many organisms reproduce by cell division.

5.4 Asexual Reproduction

Sexual Reproduction- joining of an egg and sperm cell, one from each of two parents.

• Offspring are genetically unique• Have a mixture of genes from both parents

Asexual Reproduction- creation of offspring from a single parent and does not involve the joining of gametes.

• Offspring are genetically identical to each other and the single parent.

5.4 Asexual Reproduction

Most prokaryotes reproduce through binary fission.

Binary fission- asexual reproduction of a single celled organism by division into two daughter cells genetically identical to the parent cell.

parent cell

DNA duplicates

cell begins to divide

daughter cells

5.4 Asexual Reproduction

Mitotic Reproduction

Some eukaryotes reproduce through mitosis. - Usually simple plants and animals

There are three types:

• Budding

• Fragmentation

• Vegetative Reproduction

5.4 Asexual Reproduction

Budding forms a new organism from a small projection growing on the surface of the parent.

bud

Hydra

Yeast

5.4 Asexual Reproduction

Fragmentation is the splitting of the parent into pieces that each grow into a new organism.

5.4 Asexual Reproduction

Vegetative Reproduction forms a new plant from the modification of a stem or underground structure on the

parent plant.

5.4 Asexual Reproduction

Environment determines what form of reproduction is most advantageous.

– Asexual reproduction is an advantage in consistently favorable conditions.

– Sexual reproduction is an advantage in changing conditions.

5.4 Asexual Reproduction

What are other advantages for asexual reproduction?

All organisms can potentially reproduce.

- Male and female have offspring

Don’t have to look for a mate.

- takes time, energy - need specific structures, signals, and behaviors