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Question 26

How many alleles of one gene does an organism have, and where do they come from?

  1. One allele, from one parent only
  2. Two alleles, one from each parentCorrect answer
  3. Two alleles, both from the mother
  4. Four alleles, one from each grandparent

Explanation

Chromosomes come in pairs, so a gene sits at the same place on each member of the pair, and the two copies arrive separately, one with the egg and one with the sperm. Taking both copies from the mother would leave the father contributing nothing at that gene, which fertilisation does not allow.

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Question 26: How many alleles of one gene does an organism have, and… · Genetics Basics · Questena