Biology 101 – Midterm 1 –Spring 2024 Dr. Betley, Dr. Wagner
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Arielle Levine 108
Staver Bezhani 101 102 103 104 105
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Page Questions Possible Points Points Received
2 1-11 15
3 12-15 21
4-13 MC 1-32 64
Total 100
Score total for 100 point value of exam: ________ Score total for 90 class points:___________
1
, Name:
Question 1. (7.5 points) Genetics. Crossover happens between genes far away on the same
chromosome, and one crossover event yields recombinant chromosomes out
of the 4 final chromosomes generated by meiosis. Two genes close to each other on the same
chromosome that yield fewer than the expected number of recombinants are called
genes. Such genes do not follow Mendel’s second law, the law of
. A chromatid is a chromosome that has undergone DNA
, resulting in two double stranded DNA helices. The error rate of
copying the DNA in S phase is very low, hence the two chromatids have the
DNA sequence.
Question 2. (10 points) Mutations
A. Which of these mutations is likely to destroy function of a protein? Circle all that are correct.
B. Which of them might give rise to a dominant mutation? Write D next to all that apply.
a. frameshift
b. small deletion in the coding region
c. deletion of the entire gene
d. point mutation at a wobble base that does not change the primary amino-acid sequence
e. mutation in the enhancer that leads to more binding of a transcriptional activator
f. point mutation in the coding region that enhances activity of the protein
g. small insertion in the coding region
h. mutation in the active site that allows the protein to bind an additional substrate
i. mutation in a splice donor site that leads to failure to splice out an intron
Question 3 (6 points).
2