BIOSCI 101 test quiz

Which of the following sequences correctly lists in order the steps involved in the incorporation of a protein within a cell membrane?

• synthesis of the protein on the ribosome; modification in the Golgi apparatus; packaging in the endoplasmic reticulum; modification in the vesicle

• synthesis of the protein on the lysosome; modification in the Golgi; packaging in the vesicle; distribution in the endoplasmic reticulum

• synthesis of the protein on the ribosome; modification in the endoplasmic reticulum; tagging in the Golgi; distribution via the vesicle

• synthesis of the protein on the lysosome; packaging in the vesicle; distribution via the Golgi; modification in the endoplasmic reticulum

Which of the following statements are TRUE for the Pyruvate Dehydrogenase (PDH) complex?(i) it forms acetyl CoA

          (ii) it releases CO₂ from pyruvate

          (iii) it forms NADH + H⁺

          (iv) it forms lactate from pyruvate

          (v) it is composed of four (4) enzymes

          (vi) it is composed of three (3) enzymes

          (vii) it requires succinyl-Coenzyme A

          (viii) it is inhibited by high concentrations of NADH + H⁺

• (i), (ii), (iii), (vi), (vii)

• (i), (ii), (iii), (vi), (viii)

• (i), (ii), (iv), (vi), (viii)

• (i), (ii), (iii), (v), (viii)

The genetic code is essentially the same for all organisms, we can therefore assume that: 

• The same codons in different organisms translate into different amino acids.

• The processes of transcription and translation are conducted in identical ways in all organisms.

• a gene from one organism can theoretically be expressed by another organism.

• DNA was the first genetic material.

Which of the following statements regarding translation is TRUE?

• The release factors that halt translation are tRNA molecules with anticodons that specifically bind to their respective stop codons.

• In eukaryotic cells proteins can be translated from an mRNA molecule whilst it is still being transcribed.

• Ribosomes translating polypeptides for secretion are targeted to the endoplasmic reticulum (ER), where they initially dock using a signal recognition particle (SRP).

• The protein component of ribosomes catalyses the formation of a peptide bond between the new amino acid and the growing polypeptide.

Following intense exercise, glyceraldehyde 3-phosphate dehydrogenase (GAPDH) produces NADH + H⁺. If there is very little oxygen present:

• lactate dehydrogenase oxidises NADH + H+ to NAD+ and reduces pyruvate to lactate.

• lactate dehydrogenase reduces NADH + H+ to NAD+ and oxidises lactate to pyruvate.

• procrastinase reduces FAB to not-so-FAB, and elevates fumerase.

• succinate dehydrogenase reduces FADH2 to FAD and oxidises succinate to malate.

Which of the following statement(s) are CORRECT?

          (i) Insulin stimulates glucose uptake in most tissues.

          (ii) Insulin stimulates glycogen synthesis.

          (iii) Glucagon stimulates liver glycogenolysis.

          (iv) Insulin is a powerful growth hormone.

          (v) Blood glucagon concentrations increase in response to low blood glucose.

          (vi) Insulin is secreted in response to rising levels of ATP in pancreatic islet α-cells.

• (i) (ii), (iii), (iv) and (v) are correct

• (i), (ii), (iv) and (vi) are correct

• (ii), (iii) and (iv) are correct

• All statements are correct

Experiment 1 What letters on the plots above would best illustrate what happens when Tony adds rotenone? (CI inhibitor)

• a and f

• c and d

• b and e

• c and f

Experiment 2 Tony starts again and adds oxaloacetate? (natural CII inhibitor, this feeds back on CII when the CAC is overloaded)

• a and f

• c and d

• b and e

• c and f

Experiment 3 Tony starts again and adds oligomycin? (an inhibitor of the ATP synthase)

• a and f

• c and d

• b and e

• c and f

Experiment 4 Tony starts again and this time he remembers to add ADP and Pi.

• a and f

• c and d

• b and e

• c and f