BIOL 121 Study Guide - Midterm Guide: Lactose Intolerance, Punnett Square, Wild Type
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BIOL 121 Full Course Notes
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Biology 121 practice midterm 2 answer key. Instructor: greg bole (10 marks) lactose intolerance is a common genetic condition where adults cannot digest lactose, the sugar in milk. The following is a pedigree indicating individuals with lactose intolerance: Justify your answer by referring to specific individuals from the pedigree. (5 marks) autosomal (1/2) recessive (1/2) Or 3 and 4 are both normal yet have an li son, also indicative of a recessive trait (2) 4 passes the recessive to his son which would not be possible if li were sex-linked (2: write the possible genotypes of the following individuals: (3 marks) ll (1/2) L = normal (1/2), l = lactose intolerant (1/2) (sorry, the numbers of the individuals were erased in the practice question) If she is heterozygous the probability of an affected child is 2/3 x. = 2/6 = 1/3(1 for 2/3 x and 1 for answer)
