Term | Definition |
DNA | deoxyribonucleic acid, a molecule that is present in all living cells and that contains the information that determines the traits that a living thing inherits and needs to live |
chromosomes | in a eukaryotic cell, one of the structures in the nucleus that are made up of DNA and protein; in a prokaryotic cell, the main ring of DNA |
cell cycle | the life cycle of a cell |
interphase | the period of the cell cycle during which activities such as cell growth and protein synthesis occur without visible signs of cell division |
mitosis | in eukaryotic cells, a process of cell division that forms 2 new nuclei, each of which has the same number of chromosomes |
cytokinesis | the division of the cytokinesis of a cell |
homologous | chromosomes that have the same sequence of genes and the same structure |
meiosis | a process in a cell division during which the number of chromosomes decreases to half the original number by 2 divisions of the nucleus, which results in the production of sex cells |
asexual reproduction | reproduction that does not involve the union of sex cells and and which one parent produces offspring that are genetically identical to the one parent |
sexual repuduction | reproduction in which the sex cells from two parents unite to produce offspring that share traits from both parents |
fertilization | the union of a male and female gamete to form a zygote |
heredity | the passing of genetic matierial from parent to offspring |
gene | one set of instructions for an inherited trait |
allele | one of the alternative forms of a gene that governs a characteristic, such as hair color |
genotype | the entire genetic makeup of organism; also the combination of genes for one or more specific traits |
phenotype | an organism's appearance or other detectable characteristic |
dominant | in genetics,describes an allele that is fully expressed whenever the allele is present in an individual |
recessive | describes an allele that will be masked unless the organism is homozygous for the trait |
incomplete dominance | a condition in which 2 alleles are expected such that the phenotype of a heterozygous individual is an intermediate of the 2 homozygous parents |
codominance | a condition in which 2 alleles are expressed such that the phenotype of a heterozygous individual is a combination of the phenotype of the 2 homozygous parents |
punnett square | a graph used to predict the results of a genetic cross |
probility | the likelihood that a possible future event will occur in any given instance of the event |
ratio | a comparison of two numbers using division |
pedigree | a diagram that shows the occurrence of a genetic trait in several generations of a family |