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Flashcards in Test 2 - Quiz Questions Deck (20)
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1
Q

According to this reaction: 4cyst c2+ + 8H+matrix + O2 → 4cys c3+ + 2H2O + 4H+cytosol; Humans produce about 300 ml of “metabolic water” per day. Which electron-transport complex is this referring?

A

Cytochrome c Oxidase

2
Q

Which of the following is NOT a key step in glycolysis?

A

A.) Glucose is phosphorylated at the expense of 1 ATP, rearranged to form fructose phosphate, phosphorylated again at the expense of 2nd ATP. Two phosphate groups are situated at the two ends (C1, C6) of the fructose chain.
B.) The three-carbon aldehyde is oxidized to an acid as the electron is removed from the substrate are used to reduce the coenzyme NAD+ to NADH. The C1 acid is phosphorylated to form an acyl phosphate.
C.) The phosphate group from C1 is transferred to ADP by substrate level phosphorylation. Two ATPs are formed per glucose oxidized
D.) The five-carbon biphosphate is split into a two-carbon monophosphate.
E.) These reactions result in rearrangement and dehydration of the substrate to form an enol phosphate at the C2 position that has a high phosphate group transfer potential.

Correct- D

3
Q

Efraim Racher of Cornell University, isolated the mitochondrial inner membrane spheres containing the catalytic site at which ATP formation normally occurs. In portions of the bacterial and mitochondrial ATP Synthases, Where are the α and β subunits located?

A

F1 Head

4
Q

In the Binding Change Mechanism, Boyer proposed that, at any one time, the three catalytic sites are present in different conformations, which causes them to have different affinities for nucleotides. Exercising this concept, which site would have a low affinity for nucleotides, allowing release of ATP?

A

O Conformation

5
Q
Rotary devices are extremely rare in living organisms. Which of the following contain rotating parts?
A. Eukaryotic Cells 
B. Bacterial Flagella 
C. Animal Joints 
D. ATP Synthases 
E. More than one of these
A

Correct - E

6
Q

Considering the model in which proton diffusion is coupled in the F0 complex, how many protons would need to be translocated in order to obtain a full 360° rotation of the c ring and γ subunit to yield 3 ATP molecules?

A

12

7
Q

What is the standard redox potential for the oxidation-reduction reaction involving NAD+ (NAD+ + 2H+ +2e- ↔ NADH + H+ ), when the concentration is 10-7 M (pH of 7). E’0 is ?

A

-0.320 V

8
Q

In mitochondria, MPTP and retenone are known inhibitors for which electron-transport complex?

A

Complex I

9
Q

In the electron-transport chain, the iron atom of a heme undergoes reversible transition between the Fe3+ and Fe2+ oxidation states as a result of the acceptance and loss of a single electron. Which electron carriers assists in this process?

A

Cytochromes

10
Q

Who discovered the Tricarboxylic Acid Cycle (TCA)?

A

Hans Krebs

11
Q

Fast twitch fibers in skeletal muscles utilizing glycolysis for energy, has an end product of __________?

A

Lactic Acid

12
Q

The rate of ATP hydrolysis increases more than __________ in a skeletal muscle undergoing maximal contraction compared to the same muscle at rest.

A

100-fold

13
Q
Of the 5 electron carriers, all except one are prosthetic groups.
  A. Iron-Sulfer Proteins
  B. Three Copper Atoms 
  C. Flavoproteins 
  D. Ubiquinone 
  E. Cytochromes
A

Correct D

14
Q

In the chemiosmotic mechanism, each pair of electrons transferred from NADH to oxygen by the electron-transport chain releases sufficient energy to drive the formation of approximately how many ATP molecules?

A

3

15
Q

Looking at the NAD+ and NADH couple, NAD+ represents a __________?

A

Weak Oxidizing Agent

16
Q

Mitochondrial DNA evolved from an aerobic bacterium that later became the ancestor for all eukaryotic cells. Most genes were transferred to the nucleus leaving only the most hydrophobic proteins in the inner membrane. This enzyme synthesizes mitochondrial RNA’s an is not related to enzymes in prokaryotic and eukaryotic cells but more closely related to bacterial viruses. Which enzyme are we referring to?

A

RNA Polymerase

17
Q

An important molecule in metabolism, used in many biochemical reactions, enters the TCA cycle. The catabolism of amino acids generates metabolites, which enter the matrix by special transport systems in the inner membrane. All polysaccharides, fats and proteins are broken down in metabolites to be oxidized for energy production. What molecule is being discussed?

A

Acetyl CoA

18
Q

An unusual phospholipid that is responsible for facilitating the activity of large protein complexes involved in electron synthesis, is located where in the mitochondria?

A

Inner Membrane

19
Q

Carbohydrate metabolism occurs entirely in the mitochondria

A

False

20
Q

On a nice Florida day you decide to go for a run. You have eaten breakfast, so your blood sugar (glucose) levels are high enough to sustain you. While you are running you start breathing heavily to intake enough oxygen. What purpose does that oxygen have in your mitochondria?

A

It is the final electron accepter for the ETC