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) an inversion involving chromosome 21
B) too many X chromosomes
C) a chromosomal aberration involving chromosome 1
D) a translocation between chromosome 21 and a member of the D chromosome group
E) a maternal age effect


D

Biology & Microbiology

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Unlike Giardia, most members of the Fornicata are harmless symbionts.

Answer the following statement true (T) or false (F)

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The most important events in human development occur during the ____

a. week before birth b. month before birth c. first trimester d. second trimester e. third trimester

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The cause of schistosomiasis is a ____

a. fluke b. tapeworm c. planarian d. leech e. roundworm

Biology & Microbiology

Which is not a typical feature of anthropoids?

a. Diurnal. b. Good eyesight. c. Color vision. d. Carnivorous. e. All of these

Biology & Microbiology