Nucleus

The nucleus is the heart of every cell, its control center. Inside the nucleus are forty-six threadlike structures known as chromosomes, and each one of these structures contains thousands of genes. Chromosomes and genes are made of deoxyribonucleic acid, or DNA, which transfers the heredity material from generation to generation. The genetic material of which each gene is composed contains a genetic message, or blueprint, for manufacturing one of the many proteins that make up the human...