Which of the Following Is Not a Typical Cause of Severe

question 5

Multiple Choice

Which of the following is not a typical cause of severe retardation?

• A) genetically inherited defects such as fragile-X syndrome
• B) poor prenatal nutritional habits by the mother
• C) genetically-based diseases such as PKU
• D) chromosomal abnormalities such as Down syndrome

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Definitions:

Foregut

Cephalic portion of the primitive digestive tube in the embryo.

Diencephalon

An area of the brain encompassing components like the thalamus and hypothalamus, which play a role in sensory and automatic body functions.

Hindgut

Caudal or terminal part of the embryonic gut.

Cloaca

In early embryos, the endodermally lined chamber into which the hindgut and allantois empty.