Author Question: What usually causes Down syndrome? A. Maternal infection during early pregnancy B. Fertilization ... (Read 73 times)

Arii_bell

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What usually causes Down syndrome?
 
  A. Maternal infection during early pregnancy
  B. Fertilization of an ovum containing an abnormal number of chromosomes
  C. An interaction of hereditary and environmental factors
  D. An abnormal gene transmitted by Mendelian inheritance

Question 2

A __________ is a set of HLA genes on one chromosome.
 
  A. karyotype
  B. haplotype
  C. plasmid
  D. polar body



nmyers

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Answer to Question 1

B

Answer to Question 2

B



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