3 Heredity Inheritance and Variation of Traits

Have you ever wondered why offspring from same parents are alike but never same? This is influenced by the characters or traits passed from one generation to the next via genes. Genes are short DNA segments that contain information for making specific proteins, which are responsible for the specific traits of an individual. Genes reside in a cell’s chromosomes. Every cell of any individual organism contains the identical set of chromosomes. In species that reproduce sexually, each cell contains two variants of chromosome, one inherited from each parent. Thus, sexual reproduction gives rise to a new combination of chromosome pairs with variations between parent and offspring. Environmental as well as genetic variation and the relative dominance of each of the genes in a pair play an important role in how traits develop within an individual. Complex relationships between genes and interactions of genes with the environment determine how an organism will develop and function.