Question 1

What are organisms that use metabolic processes to harvest the energy of light called?&#10;A) heterotrophs&#10;B) autotrophs&#10;C) bacteriatrophs&#10;D) photoautotrophs

Accepted Answer

Photoautotrophs are organisms that use light as their energy source to synthesize organic substances from inorganic ones, hence harvesting the energy of light through metabolic processes.

Question 2

In plants, light harvesting pigments are built into the ________ membrane.&#10;A) chloroplast&#10;B) stroma&#10;C) thylakoid&#10;D) chlorophyll

Accepted Answer

The light harvesting pigments in plants are embedded in the thylakoid membrane, which is a component of the chloroplast where the light-dependent reactions of photosynthesis take place.

Question 3

The process in which an enzyme transfers a phosphate group from a substrate molecule directly to ADP, thus forming ATP, is called&#10;A) oxidative phosphorylation.&#10;B) oxidation.&#10;C) substrate-level phosphorylation.&#10;D) metabolic phosphorylation.

Accepted Answer

Substrate-level phosphorylation is the process where a phosphate group is directly transferred from a substrate molecule to ADP to form ATP, without the involvement of an electron transport chain. This occurs in glycolysis and the Krebs cycle.

Question 4

How many pyruvate molecules are produced by glycolysis?&#10;A) 1&#10;B) 3&#10;C) 4&#10;D) 2

Accepted Answer

Glycolysis converts one molecule of glucose into two molecules of pyruvate, thus producing two pyruvate molecules.

Question 5

After reading the paragraph below, answer the question(s) that follow(s).
As a scientist employed by the Health Products and Food Branch of Health Canada, you've been asked to sit on a panel to evaluate a pharmaceutical company's application for approval of a new weight loss drug called Fat Away. The company has submitted a report summarizing the results of their animal and human testing. In the report, it was noted that Fat Away works by affecting the electron transport chain. It decreases the synthesis of ATP by making the mitochondrial membrane permeable to H⁺, which allows H⁺ to leak from the intermembrane space to the mitochondrial matrix. This effect leads to weight loss.

-The method of weight loss described for Fat Away shows that the drug is acting as a metabolic

A) feedback inhibitor.
B) oxygen carrier.
C) redox promoter.
D) uncoupler.

Accepted Answer

Fat Away makes the mitochondrial membrane permeable, allowing protons to leak across the membrane, which disrupts the proton gradient necessary for ATP synthesis in the electron transport chain. This mechanism is characteristic of an uncoupler, which disrupts the normal use of the proton gradient for ATP synthesis, leading to increased metabolic rate and, consequently, weight loss.

Question 6

After reading the paragraph below, answer the question(s) that follow(s).
As a scientist employed by the Health Products and Food Branch of Health Canada, you've been asked to sit on a panel to evaluate a pharmaceutical company's application for approval of a new weight loss drug called Fat Away. The company has submitted a report summarizing the results of their animal and human testing. In the report, it was noted that Fat Away works by affecting the electron transport chain. It decreases the synthesis of ATP by making the mitochondrial membrane permeable to H⁺, which allows H⁺ to leak from the intermembrane space to the mitochondrial matrix. This effect leads to weight loss.

-The most obvious possible side effect of Fat Away that Health Canada might be particularly concerned with would be

A) increasing the incidence of cancer.
B) the potentially lethal collapse of ATP levels in critical cells.
C) off target effects of the drug on organelles other than mitochondria.
D) the inhibition of glycolysis.

Accepted Answer

Fat Away decreases ATP synthesis by making the mitochondrial membrane permeable, which could lead to a dangerous drop in ATP levels in essential cells, potentially causing their failure.

Question 7

What is not included in the adenosine part of an ATP molecule?&#10;A) nitrogenous base&#10;B) ribose&#10;C) five-carbon sugar&#10;D) three phosphate groups

Accepted Answer

The adenosine part of an ATP molecule consists of a nitrogenous base (adenine) and a five-carbon sugar (ribose), but not the three phosphate groups, which are part of the larger ATP molecule but not the adenosine component.

Question 8

After reading the paragraph below, answer the question that follows.
In cold blooded (ectothermic) animals changes in environmental temperature are felt throughout the organism. All cellular functions will potentially be affected by these thermal changes. At low but above zero temperatures, cell membranes may effectively freeze, and this is a major problem that must be avoided by ectotherms living in temperate environments like much of Canada.

-What are the repercussions of membrane freezing?

A) It will cause the composition of the membranes to change.
B) It will prevent the movements of proteins within membranes.
C) It will cause membranes to fall apart.
D) It will cause membranes to fuse.

Accepted Answer

When cell membranes effectively freeze, the movements of proteins within the membranes are prevented, impacting cellular functions.

Deck 3: Photosynthesis , Cellular Function and How Cells Harvest Chemical Energy