NEET BIOLOGY

Detailed explanation-1: -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.

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: -As shown in the animation, a DNA molecule wraps around histone proteins to form tight loops called nucleosomes. These nucleosomes coil and stack together to form fibers called chromatin. Chromatin, in turn, loops and folds with the help of additional proteins to form chromosomes.

Detailed explanation-4: -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-5: -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.