BIOCHEM C785 2ND OA READINESS CHECK 2020
The 2nd OA Readiness Check is designed to give you additional practice with new
assessment-style questions to help prepare for success on the OA. Thus, please try to
mimic exam-like conditions by taking the test in one <2 hr sitting without any study aids
apart from your whiteboard/scrap paper.
Note: You can take the 2nd OA Readiness Check again if you're so inclined, but you
can not edit your response as you may have done with the topic questions. You will
be able to see the results afterwards.
1. What is the complementary sequence to 3’ ATG CGA ATA 5’?
*
1/1
3’ TAT TCG CAT 5’
3’ TAC GCT TAT 5’
3’ GAT AGC ATA 5’
5’ ATA AGC GTA 3’
Feedback
The correct answer is 3' TAT TCG CAT 5'. Remember complementary means “Matching or Pairing”
You have to remember to pay attention to your numbers as well as your letters (A-T, G-C, 5'-3'). The
correct answer is
3’ ATG CGA ATA 5’ (original sequence)
5’ TAC GCT TAT 3’ (complementary sequence)
But we asked for it in the 3’ direction, so mirror answer to give correct answer:
3’ TAT TCG CAT 5’
2. Which amino acid sequence would result from this
Coding DNA strand? 3’ ATG CAG ATA 5’? *
1/1
,Tyr Val
Tyr Ile
Gln Ile Ile
Asp Val
Leu His Lys
Feedback
The correct answer is Ile Asp Val. We are starting at the coding strand, and have to remember the
relationship between coding DNA and mRNA. These two strands are non-complementary and
parallel. So we copy the coding strand , change T ---> U, and then write the mRNA sequence:
3’ ATG CAG ATA 5’ coding
3’ AUG CAG AUA 5’ mRNA
Mirror by changing orientation: 5’ AUA GAC GUA 3’
Read chart Ile Asp Val (chart is in direction of 5' ---> 3')
3. Which amino acid sequence would be made from this
template DNA strand? 5’ TAT TAC CGA 3’? *
0/1
,Tyr Tyr Arg
Ile Met
Ala Ser
Val Ile Ser
His Gln
Correct answer
Ser Val Ile
Feedback
The correct answer is C because
5’ TAT TAC CGA 3’ template is complementary and antiparallel so
3’ AUA AUG GCU 5’ but it is in the wrong orientation, so mirror
5’ UCG GUA AUA 3’ and read the
chart Ser Val Ile
4. Which of the following are the correct components
for a PCR reaction? *
1/1
dNTPs, Primer, RNA Polymerase, template
RNA dNTPs, Primer, DNA Polymerase,
template DNA
ATP, Primer, mRNA polymerase; template mRNA
, Acetyl CoA, RNA primer, DNA Ligase, Template phosphate
Feedback
The correct answer is b
5. If you had a mother who is homozygous for a recessive
disease, and a father who is a heterozygous carrier, what
percentage of children will have the disease? *
1/1
0%
25%
50%
75%
100%
Feedback
The correct answer is c 50%
Homozygous recessive: aa
Heterozygous: Aa
6. Which of the following would represent a silent mutation if
this is the original sequence: 5’ AUC GUA ACA 3’? *
1/1
The 2nd OA Readiness Check is designed to give you additional practice with new
assessment-style questions to help prepare for success on the OA. Thus, please try to
mimic exam-like conditions by taking the test in one <2 hr sitting without any study aids
apart from your whiteboard/scrap paper.
Note: You can take the 2nd OA Readiness Check again if you're so inclined, but you
can not edit your response as you may have done with the topic questions. You will
be able to see the results afterwards.
1. What is the complementary sequence to 3’ ATG CGA ATA 5’?
*
1/1
3’ TAT TCG CAT 5’
3’ TAC GCT TAT 5’
3’ GAT AGC ATA 5’
5’ ATA AGC GTA 3’
Feedback
The correct answer is 3' TAT TCG CAT 5'. Remember complementary means “Matching or Pairing”
You have to remember to pay attention to your numbers as well as your letters (A-T, G-C, 5'-3'). The
correct answer is
3’ ATG CGA ATA 5’ (original sequence)
5’ TAC GCT TAT 3’ (complementary sequence)
But we asked for it in the 3’ direction, so mirror answer to give correct answer:
3’ TAT TCG CAT 5’
2. Which amino acid sequence would result from this
Coding DNA strand? 3’ ATG CAG ATA 5’? *
1/1
,Tyr Val
Tyr Ile
Gln Ile Ile
Asp Val
Leu His Lys
Feedback
The correct answer is Ile Asp Val. We are starting at the coding strand, and have to remember the
relationship between coding DNA and mRNA. These two strands are non-complementary and
parallel. So we copy the coding strand , change T ---> U, and then write the mRNA sequence:
3’ ATG CAG ATA 5’ coding
3’ AUG CAG AUA 5’ mRNA
Mirror by changing orientation: 5’ AUA GAC GUA 3’
Read chart Ile Asp Val (chart is in direction of 5' ---> 3')
3. Which amino acid sequence would be made from this
template DNA strand? 5’ TAT TAC CGA 3’? *
0/1
,Tyr Tyr Arg
Ile Met
Ala Ser
Val Ile Ser
His Gln
Correct answer
Ser Val Ile
Feedback
The correct answer is C because
5’ TAT TAC CGA 3’ template is complementary and antiparallel so
3’ AUA AUG GCU 5’ but it is in the wrong orientation, so mirror
5’ UCG GUA AUA 3’ and read the
chart Ser Val Ile
4. Which of the following are the correct components
for a PCR reaction? *
1/1
dNTPs, Primer, RNA Polymerase, template
RNA dNTPs, Primer, DNA Polymerase,
template DNA
ATP, Primer, mRNA polymerase; template mRNA
, Acetyl CoA, RNA primer, DNA Ligase, Template phosphate
Feedback
The correct answer is b
5. If you had a mother who is homozygous for a recessive
disease, and a father who is a heterozygous carrier, what
percentage of children will have the disease? *
1/1
0%
25%
50%
75%
100%
Feedback
The correct answer is c 50%
Homozygous recessive: aa
Heterozygous: Aa
6. Which of the following would represent a silent mutation if
this is the original sequence: 5’ AUC GUA ACA 3’? *
1/1
