|Allele – one of the alternative forms of a gene that governs a characteristic, such as hair color
Gene – one set of instructions for an inherited trait
Chromosome – A threadlike linear strand of DNA and associated proteins in the nucleus of eukaryotic cells that carries the genes and functions in the transmission of hereditary information.
DNA – A nucleic acid that carries the genetic information in the cell and is capable of self-replication and synthesis of RNA.
Genotype – The genetic makeup of an organism; also the combination of genes for one or more specific traits
Heredity – The genetic transmission of characteristics from parent to offspring.
Heterozygous – Having different alleles
Homozygous – Having two of the same
Inheritance – The passing of traits from parents to offspring.
Mitosis – process of cell division that form two new nuclei, each of which has the same number of chromosomes
Meiosis – process of cell division during which the number of chromosomes decreases to half the original number by two divisions of the nucleus, which results in the production of sex cells
Phenotype – The observable physical (or biochemical) characteristics of an organism, as determined by both genetic makeup and environmental influences
Probability – Measures the likelihood that something specific will occur
Punnett Square – A diagram that is used to predict an outcome of a particular cross or breeding experiment
Trait – A genetically determined characteristic or condition
Selective Breeding– the human practice of breeding animals or plants to have certain desired traits
Asexual Reproduction – reproduction that does not involve the union of sex cells and in which one parent produces offspring that are genetically identical to the parent
Interphase – The first stage of the cell cycle in which the cell grows and makes copies of chromosomes and organelles
Prophase – The first stage of mitosis and meiosis, during which the chromosomes condense and become visible, the nuclear membrane breaks down, and the spindle apparatus forms at opposite poles of the cell.
Metaphase – The stage of mitosis and meiosis during which the chromosomes are aligned along the metaphase plate.
Anaphase – The stage of mitosis and meiosis in which the chromosomes move to opposite ends of the nuclear spindle.
Telophase – The final stage of mitosis or meiosis during which the chromosomes of daughter cells are grouped in new nuclei.
Cytokinesis – The division of the cytoplasm of a cell following the division of the nucleus; marks the end of the cell cycle
Sex Chromosomes – Either of a pair of chromosomes, usually designated X or Y, that combine to determine the sex and sex-linked characteristics of an individual, with XX resulting in a female and XY in a male in mammals.
Sexual Reproduction – reproduction in which the sex cells from two parents unite to produce offspring that share traits from both parents
Homologous Chromosome – chromosomes that have the same sequence of genes and the same structure
(AC) trisomy – The condition of having three copies of a given chromosome in each somatic cell rather than the normal number of two.
(AC) karyotype – The characterization of the chromosomal complement of an individual or a species, including number, form, and size of the chromosomes.
(AC) genetic isolation – The absence of genetic exchange between populations or species as a result of geographic separation or of mechanisms that prevent reproduction.
(AC) selective pressure – Any cause that reduces reproductive success in a proportion of a population.