Asexual Reproduction

Definition: the production of offspring by a single parent.

Sexual Reproduction

Definition: the production of new living organisms by combining genetic information from two individuals of different types (sexes). In most higher organisms, one sex (male) produces a small motile gamete which travels to fuse with a larger stationary gamete produced by the other (female).

Chromatin

Definition: the material of which the chromosomes of organisms other than bacteria (i.e., eukaryotes) are composed. It consists of protein, RNA, and DNA.

Chromosome

Definition: a threadlike structure of nucleic acids and protein found in the nucleus of most living cells, carrying genetic information in the form of genes.

Sister Chromatid

Definition: Paired strands of a duplicated chromosome. 

Centromere

Definition: region where sister chromatids are joined.

Cell Cycle

Definition: a continuous process in which individual cells grow, make copies of their chromosomes and then divide to form daughter cells.

Interphase

Definition: Stage during which a cell carries out its metabolic processes & performs its functions. DNA makes DNA during this part of the cell cycle (period of growth & DNA replication).

Mitotic Phase

Definition: phase of the cell cycle when the cell is actually dividing.

Mitosis

Definition: Stage of cell division in which the cell’s nucleus divides to form 2 nuclei, each of which contains a complete set of chromosomes.

Cytokinesis

Definition: the division of the cytoplasm into two separate cells. Usually begins before mitosis is completed.

Prophase

Definition: First stage of mitosis in which the DNA condenses into chromosomes and the nuclear membrane breaks down. 

Metaphase

Definition: Second stage of mitosis in which chromosomes line up at the center of the cell.