The Cell Cycle

is the combination of DNA and proteins that make up the contents of the nucleus of a cell.

is an organized structure of DNA andprotein found in cells.

is a molecular unit of heredity of a living organism.

are two identical copies of a chromatid connected by acentromere. Compare sister chromatids to homologous chromosomes

is the process by which aeukaryotic cell separates thechromosomesin its cell nucleus into two identical sets, in two separate nuclei.

divides the nuclei,cytoplasm,organelles andcell membraneinto two cells containing roughly equal shares of these cellular components.

cells are doing nothing

the growing phase

all of the chromosomes have been replicated

production of microtubules

is a stage ofmitosis in which the chromatin condenses into double rod-shaped structures called chromosomes in which the chromatin becomes visible

align in the middle of the cell before being separated into each of the two daughter cells

Two daughter nuclei form in the cell.

refers to thesubcellular structure that segregates chromosomesbetween daughter cells duringcell division.

is the indentation of the cell's surface that begins the process of cleavage, by which animal and some algal cellsundergo cytokinesis

is a point in G1 of the animal cell cycle at which the cell becomes “committed” to the cell cycle

is a naturally occurring substance capable of stimulatingcellular growth

is one of the numerous growth factors, or proteins that regulatecell growth and division

describes a situation in which population growth is curtailed by crowding, predators and competition.

must be attached

is a special type of cell division necessary forsexual reproduction. The cells produced by meiosis are gametes orspores.

is any biological cell forming the body of an organism; that is, in a multicellular organism, any cell other than a gamete, germ cell,gametocyte or undifferentiated stem cell

is the number and appearance of chromosomes in the nucleus of a eukaryotic cell.

arechromosome pairs of approximately the same length, centromere position, and staining pattern, with genes for the same characteristics at corresponding loci

is a biological system that determines the development of sexual characteristics in an organism

is a chromosome that is not a sex chromosome, or allosome; that is to say, there is an equal number of copies of the chromosome in males and females

is a cell that fuses with another cell during fertilization (conception) inorganisms that reproduce sexually

A human somatic cell contains 46 chromosomes: 2 complete haploid sets, which make up 23 homologous chromosome pairs

cells have two homologous copies of eachchromosome, usually one from the mother and one from the father.

is the fusion of gametes to produce a new organism. In animals, the process involves the fusion of anovum with a sperm

is the initial cell formed when two gametecells are joined by means of sexual reproduction

paired and replicated chromosomes

is the pairing of two homologous chromosomes that occurs duringmeiosis.

is an exchange of genetic material between homologous chromosomes