Download 5.4 Asexual Reproduction

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.
Hydra
bud
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