Although the most frequent forms of Down syndrome are caused by a random error, nondisjunction of chromosome 21, Down syndrome occasionally runs in families. The cause of this form of familial Down syndrome is ________
A) a maternal age effect
B) a translocation between chromosome 21 and a member of the D chromosome group
C) an inversion involving chromosome 21
D) a chromosomal aberration involving chromosome 1
E) too many X chromosomes
Answer: B
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Which lobe contains the Broca's area?
a. frontal b. parietal c. occipital d. temporal e. a combination of more than one of these
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Indicate whether the statement is true or false