.4 genetic inheritance

• key terms:


  gamete - a reproductive cell of an animal or plant

  chromosome - a threadlike structure of nucleic acids and protein found in the nucleus of most living cells

  gene - The basic unit of heredity passed from parent to child

  allele - One of two or more versions of a genetic sequence at a particular region on a chromosome

  homozygous - having inherited (alleles) of a genomic marker from each biological parent. 

  heterozygous - having two different versions of the same gene

  genotype -  it describes an organism's complete set of genes

  phenotype - an individual's observable traits
• Some characteristics are controlled by a single gene
• A dominant allele is always expressed, even if only one copy is present. A recessive allele is only expressed if two copies are present (therefore no dominant allele present).