Biol 150 Summer 2022 Exam 4 KEY
NAME: ____KEY__________________________ STUDENT ID # ___KEY_____________________
By writing your name above you are agreeing to abide by the academic integrity policies of the University of Kansas and
understand that violating these policies will result in academic misconduct charges filed against you.
Multiple Choice (3 points each). Fill in the circle of the correct answer only. READ EACH QUESTION CAREFULLY!
1. A protein involved in DNA replication is causing an increased rate of double-strand breaks due to supercoiling. The
function of which protein is most likely disrupted in this situation?
o the unwinding function of helicase
o the winding stress relief function of topoisomerase II
o the fragment joining function of DNA ligase
o the proofreading function of DNA polymerase
o the strand separation function of single-stranded binding protein
2. Why does a growing DNA strand only grow in the 5’ to 3’ direction?
o DNA polymerase can only add a new nucleotide to the 5’ phosphate group of the existing nucleotide.
o DNA polymerase can only add a new nucleotide to the 3’ phosphate group of the existing nucleotide.
o DNA polymerase can only add a new nucleotide to the 5’ OH group of the existing nucleotide.
o DNA polymerase can only add a new nucleotide to the 3’ OH group of the existing nucleotide.
3. _____________ chemical bonds maintain the sugar phosphate backbone of DNA while _____________ chemical
bonds maintain base pairing.
o Ionic; van der Waals
o Phosphodiester; van der Waals
o Ionic; hydrogen
o Phosphodiester; hydrogen
o Hydrogen; ionic
4. Which of the following correctly describes the activity of ligase during DNA replication?
o Ligase would be most active on the leading strand due to the connecting of Okazaki fragments.
o Ligase would be most active on the lagging strand due to the connecting of Okazaki fragments.
o Ligase would be most active on the leading strand due to the increased activity of RNA primase.
o Ligase would be most active on the lagging strand due to the increased activity of RNA primase.
5. A population of mosquitoes is exposed to the pesticide DDT for several generations. At the end of that time, most
individuals in the population are resistant to DDT. The most likely reason is that:
o DDT caused the mutations that led to resistance.
o Some individuals in the original population had the mutations that led to resistance.
o By chance, new mutations that led to DDT resistance arose after DDT was used.
o Somatic mutations in the original population were passed on to subsequent generations.
o Random mutations in each generation made mosquitoes resistant to DDT.
6. Which of the following mutations in the coding sequence of a gene would influence the phenotype of an organism?
o Insertion
o Deletion
o Nonsynonymous
o All the above
o None of the above
1
, Biol 150 Summer 2022 Exam 4 KEY
7. Alleles
o are variant copies of a gene.
o have the same genotype.
o have the same phenotype.
o are present in two copies in gametes.
o are different genes for different traits.
8. Telomerase is
o an enzyme that adds highly repetitive DNA sequence to the end of eukaryotic chromosomes.
o active in germ and stem cells.
o inactive in somatic cells
o all the above.
o none of the above.
9. Large chromosomal inversions can cause the most problems for which of the following processes?
o mitosis
o meiosis
o mismatch repair
o base excision repair
o nucleotide excision repair
10. What stage of mitosis would be most negatively affected if kinetochore proteins were nonfunctional?
o Cytokinesis
o Telophase
o Anaphase
o Metaphase
o Prophase
11. At the start of meiosis I, how many centromeres are present in the cell?
o 12
o 23
o 46
o 92
12. A homologous chromosome pair is best described as two chromosomes that have
o the same genes in the same order but possibly with different alleles of some of the genes.
o the same alleles of the same genes in the same order.
o the same genes possibly arranged in a different order with potentially different alleles of some of the genes.
o different alleles of the same genes arranged in a different order.
o identical sequences of nucleotides.
13. Which of the following is not true regarding CDKs?
o The levels of CDK change with the cell cycle.
o They bind to cyclin.
o They function as a kinase.
o They function to control the cell cycle.
2
NAME: ____KEY__________________________ STUDENT ID # ___KEY_____________________
By writing your name above you are agreeing to abide by the academic integrity policies of the University of Kansas and
understand that violating these policies will result in academic misconduct charges filed against you.
Multiple Choice (3 points each). Fill in the circle of the correct answer only. READ EACH QUESTION CAREFULLY!
1. A protein involved in DNA replication is causing an increased rate of double-strand breaks due to supercoiling. The
function of which protein is most likely disrupted in this situation?
o the unwinding function of helicase
o the winding stress relief function of topoisomerase II
o the fragment joining function of DNA ligase
o the proofreading function of DNA polymerase
o the strand separation function of single-stranded binding protein
2. Why does a growing DNA strand only grow in the 5’ to 3’ direction?
o DNA polymerase can only add a new nucleotide to the 5’ phosphate group of the existing nucleotide.
o DNA polymerase can only add a new nucleotide to the 3’ phosphate group of the existing nucleotide.
o DNA polymerase can only add a new nucleotide to the 5’ OH group of the existing nucleotide.
o DNA polymerase can only add a new nucleotide to the 3’ OH group of the existing nucleotide.
3. _____________ chemical bonds maintain the sugar phosphate backbone of DNA while _____________ chemical
bonds maintain base pairing.
o Ionic; van der Waals
o Phosphodiester; van der Waals
o Ionic; hydrogen
o Phosphodiester; hydrogen
o Hydrogen; ionic
4. Which of the following correctly describes the activity of ligase during DNA replication?
o Ligase would be most active on the leading strand due to the connecting of Okazaki fragments.
o Ligase would be most active on the lagging strand due to the connecting of Okazaki fragments.
o Ligase would be most active on the leading strand due to the increased activity of RNA primase.
o Ligase would be most active on the lagging strand due to the increased activity of RNA primase.
5. A population of mosquitoes is exposed to the pesticide DDT for several generations. At the end of that time, most
individuals in the population are resistant to DDT. The most likely reason is that:
o DDT caused the mutations that led to resistance.
o Some individuals in the original population had the mutations that led to resistance.
o By chance, new mutations that led to DDT resistance arose after DDT was used.
o Somatic mutations in the original population were passed on to subsequent generations.
o Random mutations in each generation made mosquitoes resistant to DDT.
6. Which of the following mutations in the coding sequence of a gene would influence the phenotype of an organism?
o Insertion
o Deletion
o Nonsynonymous
o All the above
o None of the above
1
, Biol 150 Summer 2022 Exam 4 KEY
7. Alleles
o are variant copies of a gene.
o have the same genotype.
o have the same phenotype.
o are present in two copies in gametes.
o are different genes for different traits.
8. Telomerase is
o an enzyme that adds highly repetitive DNA sequence to the end of eukaryotic chromosomes.
o active in germ and stem cells.
o inactive in somatic cells
o all the above.
o none of the above.
9. Large chromosomal inversions can cause the most problems for which of the following processes?
o mitosis
o meiosis
o mismatch repair
o base excision repair
o nucleotide excision repair
10. What stage of mitosis would be most negatively affected if kinetochore proteins were nonfunctional?
o Cytokinesis
o Telophase
o Anaphase
o Metaphase
o Prophase
11. At the start of meiosis I, how many centromeres are present in the cell?
o 12
o 23
o 46
o 92
12. A homologous chromosome pair is best described as two chromosomes that have
o the same genes in the same order but possibly with different alleles of some of the genes.
o the same alleles of the same genes in the same order.
o the same genes possibly arranged in a different order with potentially different alleles of some of the genes.
o different alleles of the same genes arranged in a different order.
o identical sequences of nucleotides.
13. Which of the following is not true regarding CDKs?
o The levels of CDK change with the cell cycle.
o They bind to cyclin.
o They function as a kinase.
o They function to control the cell cycle.
2
