AP BIOLOGY

Detailed explanation-1: -A structure found inside the nucleus of a cell. A chromosome is made up of proteins and DNA organized into genes. Each cell normally contains 23 pairs of chromosomes.

Detailed explanation-2: -Nucleotides are arranged in two long strands that form a spiral called a double helix.

Detailed explanation-3: -The nucleus, formed by a nuclear membrane around a fluid nucleoplasm, is the control center of the cell. Threads of chromatin in the nucleus contain deoxyribonucleic acid (DNA), the genetic material of the cell.

Detailed explanation-4: -The nucleus (Figure 6) serves as the cell’s command center, sending directions to the cell to grow, mature, divide, or die. It also houses DNA (deoxyribonucleic acid), the cell’ s hereditary material.

Detailed explanation-5: -DNA has two strands that twist into the shape of a spiral ladder called a helix. DNA is made up of four building blocks called nucleotides: adenine (A), thymine (T), guanine (G), and cytosine (C).