AP BIOLOGY

Detailed explanation-1: -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 . Its transcription is dormant.

Detailed explanation-2: -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-3: -Chromosomes are bundles of tightly coiled DNA located within the nucleus of almost every cell in our body. Humans have 23 pairs of chromosomes.

Detailed explanation-4: -The centromere is also where spindle fiber microtubules attach during mitosis. The spindles separate sister chromatids from each other. The DNA double helix wraps around proteins (2) and tightly coils a number of times to form a chromosome (5). This figure shows the complexity of the coiling process.

Detailed explanation-5: -Chromosomes are coiled structures made of DNA and proteins. Chromosomes are the form of the genetic material of a cell during cell division. It is this coiled structure that ensures proper segregation of the chromosomes during cell division. During other phases of the cell cycle, DNA is not coiled into chromosomes.