AP BIOLOGY

Detailed explanation-1: -In the nucleus of each cell, the DNA molecule is packaged into thread-like structures called chromosomes. Each chromosome is made up of DNA tightly coiled many times around proteins called histones that support its structure.

Detailed explanation-2: -Histone proteins are tightly coiled up inside the DNA as chromatin fibers, which further compact to create chromosomes. Condensed DNA is found in a tightly packed area of chromatin called heterochromatin.

Detailed explanation-3: -The entire structure is called a nucleosome, each of which includes an octamer of histone proteins and 146 to 147 base pairs of DNA. [2][3] The millions of nucleosomes tightly coil the continuous DNA strand into chromatin which is further condensed into the chromosome classically visualized during cell division.

Detailed explanation-4: -Single-stranded DNA is the single DNA strand that is created during the replication process of DNA. The replication of single-stranded DNA forms two separate single-stranded chromosomes that join together to form double-stranded DNA (dsDNA).

Detailed explanation-5: -Chromosomes also contain proteins that help DNA exist in the proper form. Humans typically have 23 pairs of chromosomes, or 46 chromosomes in total. Chromosomes are made up of long strands of DNA, which contain all the body’s genes.