Asexual Reproduction Advantages and Disadvantages

Binary Fission  Bacteria reproduce by a process called binary fission  Binary fission: a copy of their single chromosome is produced and then the cell divides in half so that one half gets one chromosome and the other half gets the other chromosome  Because the chromosome was duplicated, each new cell receives a complete set of hereditary information

Asexual Reproduction  Binary fission is an example of asexual reproduction in single celled organisms  Multi-cellular organisms that reproduction asexually is more complex and occurs in the nucleus through mitosis.  Only types of asexual reproduction are: Budding Fragmentation Gemmules (Internal Buds) Regeneration

Budding  Offspring grows out of the body of the parent  Hydras exhibit this type of reproduction  Jellyfish also  reproduce through  budding

Sponges  Sponges reproduce asexually through gemmules (internal buds)  A parent releases a specialized mass of cells that can develop into an offspring

Fragmentation  In this form of asexual reproduction, the body of the parent breaks into distinct pieces, each of which can produce an offspring.  Molds, yeast and some mushrooms reproduce in this way.

Regeneration  If a piece of a parent is detached, it can grow and develop into a completely new individual.  Flatworms use this type of asexual reproduction.

Mitosis  In a complex cell going through asexual reproduction, the nucleus divides during a process called mitosis.  Mitosis ensures that each new cell received the same number and kinds of chromosomes that were present in the parent cell.  In both binary fission/mitosis, these processes produce two offspring with hereditary information that is identical to the parent cell.

Mitosis

Advantages and Disadvantages of Asexual Reproduction  Advantage: an organism does not have to wait for a partner to be able to produce offspring.  Disadvantage: the offspring are exactly like the parents (no variation in DNA).  Asexual reproduction does not allow organisms to have variation from generation to generation. (could cause an organism to die out if changes occur in ecosystem)