GENETICS AND EVOLUTION
MOLECULAR BASIS OF INHERITANCE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Cell Regeneration
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Replication
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Making of Proteins
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Building Template Strands
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Detailed explanation-1: -The packaging of DNA into nucleosomes shortens the fiber length about sevenfold. In other words, a piece of DNA that is 1 meter long will become a “string-of-beads” chromatin fiber just 14 centimeters (about 6 inches) long.
Detailed explanation-2: -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-3: -Condensing DNA into chromosomes prevents DNA tangling and damage during cell division.
Detailed explanation-4: -DNA packing tends to prevent gene expression by preventing transcription proteins from contacting the DNA. Cells seem to use such higher levels of packing for long-term inactivation of genes.