MAMMALIAN GENETICS BCH5413 EXAM 4 UPDATED ACTUAL QUESTIONS AND CORRECT ANSWERS

MAMMALIAN GENETICS BCH5413 EXAM 4 UPDATED
ACTUAL QUESTIONS AND CORRECT ANSWERS

Question:
1. DNA can be both replicated and transcribed into mRNA,
which can be translated into protein

Answer:
What is the central dogma of molecular biology?

Question:
2. True (this is due to intrastrand crosslinking, in which
adjacent nucleotides basepair, causing bubbling)

Answer:
T/F: the addition of bulky aromatic rings and/or exposure to UV light can cause
the DNA to "bubble."

Question:
3. True

Answer:
T/F: chemotherapy can cause both single and double-stranded breaks in DNA.

Question:
4. Damaged DNA can lead to incorrect base pairing, which
can lead to mutations (permanent changes in the DNA
sequence)

Answer:
Why is it very important that damaged DNA is repaired?

Question:
5. Guanine with a new -C=O bond in place of the original
=C-H2 bond

Answer:
What is 8-oxyguanine?

Question:
8-oxyguanine flips over, causing it to hydrogen bond with
adenine (instead of cytosine) and become a thymine in
the next round of DNA replication

Answer:
What happens to GC base pairing when guanine is converted to 8-oxyguanine?

,Question:
7. 2 (instead of guanine's normal 3)

Answer:
How many hydrogen bonds does 8-oxyguanine have with its partner nucleotide?

Question:
8. An agent used in chemotherapy that has lots of bulky
side chains

Answer:
What is cisplatin?

Question:
9. Bulky adducts (DNA "bubbles") caused by the addition of
large sidechains and/or intrastrand crosslinking caused
by cisplatin binding to 2 adjacent guanines

Answer:
What type of DNA damage can be caused by cisplatin?

Question:
10. The addition of cisplatin causes damage to DNA, so
introducing it to cancer cells can help damage/kill them

Answer:
Why is cisplatin an effective treatment for cancer?

Question:
11. What type of mutation occurs when a single basepair is changed, but the amino
acid stays the same?

Answer:
Silent mutation

Question:
12. Missense mutation

Answer:
What type of mutation occurs when a single basepair is changed, changing the
amino acid?

Question:
13. Nonsense mutation

Answer:
What type of mutation occurs when a single basepair is changed, causing the
formation of a stop codon?

, Question:
14. False (mutations in the active site are more detrimental
than mutations in outer regions of the protein)

Answer:
T/F: mutations in any part of a protein's sequence can be equally damaging.

Question:
15. Frameshift mutation

Answer:
What type of mutation occurs when a single basepair is inserted or deleted?

Question:
16. A single-stranded break in the DNA

Answer:
What kind of DNA damage is recognized by the BER repair proteins?

Question:
17. Each type of glycosylase recognizes a different type of
DNA damage

Answer:
Why is it necessary to have multiple types of glycosylases?

Question:
18. Mono-functional glycosylases will only cleave an
incorrect base; bi-functional glycosylases will cleave
both an incorrect base and the DNA's backbone

Answer:
How does BER differ if a mono-functional vs. a bi-functional glycosylase is used?

Question:
19. False ("short-patch" DNA repair is when only 1 base is
removed and replaced)

Answer:
T/F: "Short-patch" DNA repair refers to multiple bases being removed and
replaced along a short section of DNA.

Question:
20. FEN1 (cleaves the "flap" of incorrect bases)

Answer:
What is the additional enzyme that's required for "long-patch" DNA repair before
ligase can seal up the nick?