10 questions in 10 minutes

Q1-2: These questions are about Meselon and Stahl’s DNA replication experiments.

Meselson-stahl_experiment_diagram

1.  These experiments showed that DNA replication was ...

  • A. conservative
  • B. semi conservative
  • C. dispersive
  • D. Random
2. Meselon and Stahl grew E. Coli in a medium containing 15N  for several generations.  Which part of the DNA molecule contains 15N?
  • A. deoxyribose
  • B. phosphate
  • C. nucleotide
  • D. adenosine

3. What is the role of the enzyme helicase in DNA replication?

I. ‘Unzips’ the DNA
II. Uses energy from ATP
III. Breaks the covalent bonds between phosphate and adjacent deoxyribose
IV. Breaks the hydrogen bonds between complementary base pairs
  • A. I only
  • B. I, II and III only
  • C. I and III only
  • D. I, II and IV only
4. For a new strand of DNA to be made which of the following is not required?
  • A. DNA polymerase
  • B. nucleotides
  • C. template strand of DNA
  • D. ribosomes
5. What is PCR used for?
  • A.   To separate pieces of DNA
  • B.   To genetically modify DNA
  • C.   To amplify DNA
  • D.   To identify the sequence of DNA
6. Why is Taq DNA polymerase used in PCR (Polymerase Chain Reaction)?
  • A. It is cheap
  • B. It is not denatured at 80oC
  • C. It is only found in bacteria
  • D. It does not affect the product of DNA replication
7. Gel electrophoresis is used to separate fragments of DNA. What two factors dictate how far the DNA molecules travel?
  • A. Their size and net positive charge
  • B. Their size and net negative charge
  • C. Their net negative charge and proximity to the cathode
  • D. Their size and proximity to the cathode
8. DNA evidence was collected from a mother (M), and three possible fathers of a child (Ch).
What is the pattern of inheritance in this pedigree shown below?

DNA_paternity_testing_pedigree_chart

 Helixitta
c.c. BY-SA 3.0
  • A.   The child is related to father 1
  • B.   The child is related to father 2
  • C.   The child is related to father 3
  • D.   The child is not related to any possible father
9. What strategy can be employed to directly increase the reliability of DNA profiling in forensics by reducing the occurrence of false matches?
  • A. Increasing the number of markers used
  • B. Decreasing the voltage applied during gel electrophoresis for better resolution
  • C. Using a larger gel size to accommodate more repeats in a single run
  • D. Extending the running time of electrophoresis to ensure complete separation
10. What do PCR (Polymerase Chain Reaction) and DNA replication have in common?

I. Use of primers
II. Complementary base pairing
III. Template strand of DNA needed
IV. Breakage of covalent bonds between bases
  • A. I and II only
  • B. II and III only
  • C. I, II, and III only
  • D. II, III, and IV only


Background Image by Tim Tim
CC-BY-SA 4.0