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DNA and chorosomes
5.1, 5.2, 6.1, 6.2, 8.1, 8.2, 8.3 vocab
| Term | Definition |
|---|---|
| cell cycle | pattern of growth, DNA replication, and cell division that occurs in a eukaryotic cell. |
| mitosis | process by which a cell divides its nucleus and contents. |
| cytokinesis | process by which the cell cytoplasm divides. |
| chromosome | long, continuous thread of DNA that consists of numerous genes and regulatory information. |
| histone | protein that organizes chromosomes and around which DNA wraps. |
| chromatin | loose combination of DNA and that is present during interphase. |
| chromatid | one half of a duplicated chromosome. |
| centromere | region of condensed chromosome that looks pinched; where spindle fibers attach during meiosis and mitosis. |
| somatic cell | cell that makes up all of the body tissues and organs except gametes. |
| gamete | sex cell; an egg or a sperm cell. |
| homologous chromosome | chromosomes that have the same length, appearance. |
| autosome | chromosome that contains genes for characteristics not directly related to the sex of the organism. |
| sex chromosome | chromosome that directly controls the development of sexual characteristics. |
| sexual reproduction | process by which two gametes fuse and offspring that are a genetic mixture of both parents are produced. |
| fertilization | fusion of an egg and sperm cell. |
| diploid | cell that has two copies of each chromosome, one from an egg and one from a sperm. |
| haploid | cell that has only one copy of each chromosome. |
| meiosis | form of nuclear division that divides a diploid cell into haploid cells; important in forming gametes for sexual reproduction. |
| gametogenesis | process by which gametes are produced through the combination of meiosis and other maturational changes. |
| sperm | male gamete. |
| egg | female gamete. |
| polar body | haploid cell produced during meiosis in the female of many species; these cells have little more than DNA and eventually disintegrate. |
| bacteriophage | virus that infects bacteria. |
| nucleotide | monomer that forms DNA and has a phosphate group, sugar, and a nitrogen-containing base. |
| double helix | model that compares the structure of a DNA molecule, in which two strands wind around one another, to that of a twisted ladder. |
| base pairing rules | rule that describes how nucleotides form bonds in DNA; adenine (A) always bonds with thymine (T), and guanine (G) always bonds with cytosine (C). |
| replication | process by which DNA is copied. |
| DNA polymerase | enzyme that makes bonds between nucleotides, forming an identical strand of DNA during replication. |