Biochemistry C785 Readiness Check 2020 –

Western Governors University

Biochemistry Readiness Check

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: Responses cannot be edited. You will be

able to see the results and feedback after submitting the test. A score of 70% is required

for OA approval. If you score below 70%, please speak with a Course Instructor via

appointment to discuss next steps prior to retaking this test.

Points:

54/67

1

What is the complementary sequence to 3’ ATG CGA ATA 5’?

(1/1 Points)

3’ TAT TCG CAT 5’

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’

3’ TAC GCT TAT 5’

3’ GAT AGC ATA 5’

5’ ATA AGC GTA 3’

2

Which amino acid sequence would result from this Coding DNA strand? 3’ ATG CAG

ATA 5’?

(0/1 Points)

Tyr Val Tyr

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') If you chose Tyr Val Tyr, this answer is incorrect

because this is the amino acid sequence that results from the mRNA 5' UAC GUC UAU

3' which would have been complementary to the given coding strand. Coding DNA is

non-complementary and parallel to mRNA.

Ile Gln Ile

Ile Asp Val

Leu His Lys

3

Which amino acid sequence would be made from this template DNA strand? 5’ TAT TAC

CGA 3’?

(1/1 Points)

Tyr Tyr Arg

Ile Met Ala

Ser Val Ile

The correct answer is Ser Val Ile 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

Ser His Gln

4

Which of the following are the correct components for a PCR reaction?

(1/1 Points)

dNTPs, Primer, RNA Polymerase, template RNA

dNTPs, Primer, DNA Polymerase, template DNA

The correct answer is dNTPs, Primer, DNA Polymerase, template DNA. Notice that all

components are about DNA. The Primer is even a DNA Primer.

ATP, Primer, mRNA polymerase; template mRNA

Acetyl CoA, RNA primer, DNA Ligase, Template phosphate

5

Assuming 100% reaction efficiency, how many DNA copies will be produced after 5 PCR

cycles, if we begin with 1 DNA template?

(1/1 Points)

16

32

The correct answer is 32. 2x2x2x2x2=32

64

10

6

Which of the following would represent a silent mutation if this is the original sequence:

5’ AUC GUA ACA 3’?

(1/1 Points)

5’ AUC GGA ACA 3’

5' AUA GUA ACA 3'

The correct answer is 5' AUC GUA ACA 3' Ile Val Thr

5’ AUG GUA ACA 3’

5’ AUC GCA ACA 3’

7

If the original coding sequence is 5’ CGA TAC TTC AGA 3’ and it is mutated to 5' CGA

TAT TTC AGA 3', what type of mutation would have taken place?

(0/1 Points)

Silent

Missense

The correct answer is silent mutation. The nucleotide sequence changes, but it codes for

the same amino acid. The coding sequence 5' TAC 3' corresponds to the mRNA sequence

5' UAC 3' (Tyr), and the coding sequence 5' TAT 3' corresponds to the mRNA sequence

5' UAU 3' (Tyr). Since the C changed to at T, this is a point mutation. If the point

mutation results in the same amino acid in the new sequence as in the original

sequence, the point mutation is a silent mutation.

Nonsense

Insertion

8

This learning objective is now tested in a different WGU course than Biochemistry.

Please select True.

True

The correct answer is Option 1 because an autosomal dominant disorder would be

inherited on numbered chromosomes, not sex chromosomes X or Y. Also, at least one

dominant allele (yellow box) needs to be present for the individual to have the dominant

disease.

False

9

This learning objective is now tested in a different WGU course than Biochemistry.

Please select True.

True

The correct answer is X- linked recessive because parents (carriers) do not have it (II-5-

6) but a child does (III-5). You will get the same result if you consider parents (carriers)

(I-1-2), who do not have the trait, but a child does (II-3). A third option that gives the 

same result (X-linked recessive) is by considering parents (carriers) who do not have the

trait (III-1-2), and their child does (IV-1). The pattern is recessive because the selected

parents are carriers, and it is X-linked because only males have the trait.

False