Sickle Cell Anemia (A Serious Heritable Disease)appears to Be Maintained

question 24

Multiple Choice

Sickle cell anemia (a serious heritable disease) appears to be maintained via balancing selection in some African populations because heterozygous carriers for the fully recessive disease allele are less affected by malaria parasites.Is this a case of antagonistic pleiotropy?

• A)Yes, the same allele has positive effects on one trait and negative effects on another trait.
• B)Yes, wild-type and sickle cell alleles have antagonistic effects.
• C)No, there is no time lag between the two traits (i.e., as in early vs. late acting).
• D)No, it involves a dominance interaction between the wild-type and the sickle cell allele.

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Definitions:

Positive Symptoms

Refers to an excess or distortion in normal functions or behaviors, often associated with psychiatric conditions like schizophrenia.

Fluid-filled Areas

Spaces within the body or a biological structure that contain liquid; often refers to cavities or sacs filled with fluid.

Thalamus

A structure in the brain situated above the brainstem that acts as the main relay station for information flowing to and from the cortex, playing a crucial role in processing sensory information and sleep regulation.

Delusions of Persecution

False beliefs that one is being persecuted, watched, or conspired against, often seen in paranoid disorders.