In Some Parts of Africa, the Frequency of Heterozygosity for the Sickle-Cell

question 45

Multiple Choice

In some parts of Africa, the frequency of heterozygosity for the sickle-cell anaemia allele is unusually high, presumably because this reduces the frequency of malaria. Such a relationship is related to which of the following?

• A) Mendel's law of independent assortment.
• B) Mendel's law of segregation.
• C) Darwin's explanation of natural selection.
• D) The malarial parasite changing the allele.

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Definitions:

Digestive Tract

Mouth, oropharynx, esophagus, stomach, small intestine, and large intestine.

Apical Ectodermal Ridges

Thickened regions of ectoderm important for the induction and growth of the limbs in developing embryos.

Frontonasal Process

The embryonic precursor to the forehead and the bridge of the nose, playing a significant role in facial development.

Maxillary Processes

Embryological structures that contribute to the formation of the upper jaw (maxilla) and other facial features.