Animal Bio Chapter 21: Genetic Inheritance

Chromosomes

Where most genetic material is stored

Diploid

2 sets of chromosomes; most animals (and humans) have this

Homologous Chromosomes

Two chromosomes of the same type

Gene

Segment of DNA that determines an inherited trait; encode proteins, which determine our inherited traits

Alleles

Different versions of the same gene; can be dominant or recessive with dominant as uppercase and recessive as lowercase

Genotype

Homozygous Dominant (2 dominant), Homozygous Recessive (2 recessive), and Heterozygous (2 different alleles)

Phenotype

Describes appearence of a genotype

Gametes

Get one copy of each gene

Mutations

A change in DNA sequence; most genetically inherited disorders are caused by mutations; can produce damaged protein that does not function properly

Somatic Cells

Body cells (all cells that are not germ line cells)

Germ Line Cells

Give rise to gametes (egg and sperm); mutations in these cells are passed to offspring

Pedigree

Insight into the inheritance pattern of a genetically inherited condition

Autosomal Recessive/Dominant

Location of mutated allele; most affected individuals have parents who are unaffected but are carriers of the mutated allele

X-linke

Females have two X chromomsomes nad have two gene copies for genes on the X chromosome; males have one X chromosome and have only one copy for genes on the X chromosome

Changes in Chromosome Number

Changes in chromosome number occurs when chromosomes don’t separate properly during gamete formation; there are only 5 changes in chromosome number that are compatible with life