HEREDITY
MUTATIONS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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It is harmful
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It is helpful
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It is considered neutral
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It does noting either way to help or harm the organism
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Detailed explanation-1: -Sickle cell disease (SCD) is a genetic disorder caused by a mutation in both copies of a person’s HBB gene. This gene encodes a component of hemoglobin, the oxygen-carrying protein in red blood cells. The mutation causes hemoglobin molecules to stick together, creating sickle-shaped red blood cells.
Detailed explanation-2: -As mentioned, sickle-cell anemia is the result of a change in a single nucleotide, and it represents just one class of mutations called point mutations.
Detailed explanation-3: -The parasite triggers the SCT hemoglobin to sickle. The immune system then clears the infected red blood cells before the parasite can complete its life cycle and infect other red blood cells. This means fewer parasites and milder illness.
Detailed explanation-4: -There are many genes that influence just this. For example, a genetic variance causing sickle cell anemia actually protects against another disease, malaria. This explains why the gene for sickle cell anemia is found in about 7% of the population in malaria-stricken regions, but is virtually nonexistent elsewhere.