Though Sickle-Cell Anaemia Is Frequently Lethal for Individuals Who Are

question 11

Multiple Choice

Though sickle-cell anaemia is frequently lethal for individuals who are homozygous for the sickle-cell allele,natural selection seems to have maintained that allele in certain geographic locations.A likely explanation for this observation is that

• A) the forward mutation rate to sickle-cell is much higher in those regions.
• B) individuals with sickle-cell anaemia live longer and have more children.
• C) reversion from sickle-cell to wild-type is prevented in some populations.
• D) individuals who are heterozygous for the sickle-cell allele are protected from malaria.
• E) only certain populations have been tested for the presence of the sickle-cell allele.

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Definitions:

Psychiatric Patients

Individuals undergoing treatment for mental disorders, who may receive psychiatric care in various settings.

Lifetime Prevalence

The proportion of individuals in a population who have ever experienced a particular disorder or condition at any time in their lives.

Schizophrenia

A significant psychological condition marked by alterations in cognition, sensory perceptions, feelings, speech, self-identity, and actions.

Neurotransmitter Receptors

Proteins located on neuronal cell membranes that bind neurotransmitters and initiate cellular responses.