EVOLUTION
SOURCES OF VARIATION IN A POPULATION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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tightly coiled DNA
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a short section of the DNA code which codes for a characteristic
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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: -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-3: -DNA is not always tightly coiled and packed to form the visible chromosomes seen during cell division. All other times, the long DNA molecule and special proteins combine to form chromatin which exists as a loosely coiled structure..
Detailed explanation-4: -This is accomplished by wrapping the DNA around structural histone proteins, which act as scaffolding for the DNA to be coiled around. The entire structure is called a nucleosome, each of which includes an octamer of histone proteins and 146 to 147 base pairs of DNA.
Detailed explanation-5: -It is this coiled structure that ensures the proper segregation of the chromosomes during cell division. During other phases of the cell cycle, DNA is not coiled into chromosomes.