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Quinn Science C 3
Cell Cycle and Heredity
| Term | Definition |
|---|---|
| cell cycle | the life cycle of a cell; in eukaryotes it consists of chromosome duplication, mitosis, and cytokinesis |
| chromosome | a coiled structure of DNA and protein that forms in the cell nucleus during cell division |
| binary fission | the simple cell division in which one cell splits into two; used by bacteria |
| homologous chromosomes | chromosomes with matching information |
| chromatids | identical chromosome copies |
| centromere | the region that holds chromotids together when a chromosome is duplicated |
| mitosis | nuclear division in eukaryotic cells in which each cell receives a copy of the original chromosomes |
| cytokinesis | the process in which cytoplasm divides after mitosis |
| heredity | the passing of traits from parent to offspring |
| dominant trait | the trait observed when at lease one dominant allele for a characteristic is inherited |
| recessive trait | a trait that is apparent only when two recessive alleles for the same characteristic are inherited |
| genes | segments of DNA that carry hereditary instructions and are passed from parent to offspring; located on chromosomes |
| genotype | the inherited combination of alleles |
| phenotype | an organism's inherited appearance |
| probability | the mathematical chance that an event will occur |
| sex cells | an egg or sperm; a sex cell carries half the number of chromosomes found in other body cells |
| meiosis | cell division that produces sex cells |
| sex chromosomes | the chromosomes that carry genes that determine the sex or gender of the offspring |
| punnett square | used to visualize all the possible combinations of alleles from the parents |
| alleles | different forms of a single gene |
| eukaryotic cell | a cell that contains a central nucleus and a complicated internal structure |
| prokaryotic cell | a cell that does not have a nucleus or any other membrane-covered organelles; also called a bacterium |
| Gregor Mendel | studied the way traits are passed from parents to offspring using pea plants |
| self-pollinating plant | contains both the male and female reproductive structures |
| true breeding plant | a plant that always produces offspring with the same traits as the parents; self pollinates |
| cross-pollination | the crossing of two different forms of a single trait |
| DNA | deoxyribonucleic acid; hereditary material that controls all the activities of a cell, contains the information to make new cells, and provides instructions for making proteins |
| number of chromosomes in a human sex cell | 23 |