CELL STRUCTURES AND FUNCTION
CELL CYCLE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Chromatids
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Nucleus
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DNA
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None of the above
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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: -Each chromosome within a cell has its own strand of DNA. So with 23 pairs of human chromosomes, every human cell should host 46 strands of DNA-each wrapped around hundreds of thousands of histones. This tight coiling helps the body to pack its long DNA molecules into very tiny spaces.
Detailed explanation-4: -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. Instead, it exists as a grainy material called chromatin.
Detailed explanation-5: -A chromosome is made up of proteins and DNA organized into genes. Each cell normally contains 23 pairs of chromosomes.