asexual reproduction

Reproduction without sex. In this form of reproduction, a single organism or cell makes a copy of itself.

sexual reproduction

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

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

chromosome

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

A sister chromatid refers to the identical copies (chromatids) formed by the DNA replication of a chromosome, with both copies joined together by a common centromere.

centromere

the region of a chromosome to which the microtubules of the spindle attach, via the kinetochore, during cell division.

cell cycle

 is the series of events that take place in a cell leading to duplication of its DNA (DNA replication) and division of cytoplasm and organelles to produce two daughter cells. 

interphase

the resting phase between successive mitotic divisions of a cell, or between the first and second divisions of meiosis.

mitotic phase

a multistep process during which the duplicated chromosomes are aligned, separated, and move into two new, identical daughter cells.

mitosis

a type of cell division that results in two daughter cells each having the same number and kind of chromosomes as the parent nucleus, typical of ordinary tissue growth.

cytokinesis

the cytoplasmic division of a cell at the end of mitosis or meiosis, bringing about the separation into two daughter cells.

prophase

the first stage of cell division, before metaphase, during which the chromosomes become visible as paired chromatids and the nuclear envelope disappears. The first prophase of meiosis includes the reduction division.

metaphase

the second stage of cell division, between prophase and anaphase, during which the chromosomes become attached to the spindle fibers.