Teamup Q Section 1

Question 1

W1: Which of the following is considered to be TRUE regarding the evolution of eukaryotes?

a. Eukaryotes evolved before prokaryotes.
b. The precursor cell to aerobic eukaryotes contained bacterial endosymbionts that had lost all their original DNA.
c. The evolution of the endoplasmic reticulum and nuclear envelope are thought to have been gradual processes and not a result of endosymbiosis.
d. The evolution of chloroplasts occurred before endosymbiosis of an aerobic prokaryote.

Answer 1

c. The evolution of the endoplasmic reticulum and nuclear envelope are thought to have been gradual processes and not a result of endosymbiosis.

Question 2

W1: Which of the following is a ribonucleoside, but not a nucleotide?

ATP
dATP
adenine + ribose
adenine + ribose + phosphate

Answer 2

adenine + ribose

Question 3

W4: The image below is from Wikipedia (https://en.wikipedia.org/wiki/Helicase).

Observe the following in the figure:
* The gap between the single nucleotide RNA primer and the rest of the Okazaki fragment.
* The position of the helicase.
* The position of the DNA polymerase on the lagging strand.

How many of these observations highlight inaccuracies in the figure?
0
1
2
3

Answer 3

3
- the okazaki should be near helicase and primer
- helicase isn’t in the middle, it’s either on leading or lagging; more often the lagging
- dna poly on lagging strand is weird bc dna poly should be by primer and filling in the next okazaki fragment

Question 4

W4: Solving the “end replication problem” (preventing the loss of information on lagging strands) does NOT require…
an RNA primer.
an RNA template.
a DNA polymerase.
a helicase.

Answer 4

a helicase

Question 5

W4: In cancers, cells continually replicate their DNA and divide, growing out of control. This leads to the formation of tumors and destruction of the body. Which of the following would be the LEAST effective cancer treatment?
A drug that stops topoisomerases in cancer cells.
A drug that stops pyrimidine dimers in cancer cells.
A drug that stops single strand binding proteins in cancer cells.
A drug that stops telomerases in cancer cells.

Answer 5

A drug that stops pyrimidine dimers in cancer cells.

Question 6

W4: You have identified a patient with cancer, performed a biopsy of the cancerous tumour, and have sequenced the genome in some of the cells from the biopsy. When you analyze the genome sequences from the cancer cells, you find many more A/T bases where you would have expected G/C bases (compared with healthy cells). What is the most likely issue?
A problem with nucleotide excision repair.
A problem with strand-directed mismatch repair.
A problem with base excision repair.
A problem with 3’ to 5’ exonuclease repair activity.

Answer 6

A problem with base excision repair.

Question 7

W6: (there is a photo attached) for the first q so not included

Question 8

W6. Which of the following statements is TRUE?
Initiation of translation requires an initiator tRNA and initiation factors that bind to the large ribosomal subunit before the small ribosomal subunit binds to mRNA.
The Shine-Dalgarno sequence allows for multiple translation initiation sites on a eukaryotic mRNA.
Because the start codon codes for methionine, eukaryotic mRNAs cannot code for methionine at any other position in their sequences.
Translation initiation is important for determining the reading frame.

Answer 8

Translation initiation is important for determining the reading frame.

Question 9

W6. Which of the following is TRUE of both prokaryotic and eukaryotic translation?
The requirements for complementary base-pairing between the codon and anti-codon is strictest for the first two nucleotides, and often more flexible for the third nucleotide.
The 5’ cap binding proteins are removed before initiation factors for translation can bind the mRNA.
fMethionine is attached to the tRNA that will bind in the A-site when translation is initiated.
There are the same number of amino-acyl tRNA synthetases as there are tRNAs.

Answer 9

The requirements for complementary base-pairing between the codon and anti-codon is strictest for the first two nucleotides, and often more flexible for the third nucleotide.

Question 10

W6. Imagine that you are working for a company that is developing antibiotics to combat bacterial infections in humans. Which of the following would be your BEST approach to this task?
Finding a chemical or protein that induces mutations in genes that code for snRNPs.

Finding a chemical or protein that prevents the interaction of translation initiation factors with the PolyA binding protein.

Finding a chemical or protein that binds to EF-G and prevents it from hydrolyzing GTP.

Finding a chemical or protein that blocks the sigma factor from binding to RNAP II.

Answer 10

Finding a chemical or protein that binds to EF-G and prevents it from hydrolyzing GTP.