Question 1

Which of the following best describes the process shown in the first image, where ADP is converted to ATP?

Accepted Answer

Substrate-level phosphorylation, where a phosphate group is directly transferred from a high-energy intermediate to ADP.

Question 2

Based on the second image, what is the main difference between respiration and fermentation in terms of ATP production?

Accepted Answer

Respiration uses an electron transport chain and produces more ATP, while fermentation does not use an electron transport chain and produces less ATP.

Question 3

In the third image, what is the primary function of the electron transport chain (ETC) in prokaryotes?

Accepted Answer

To create a proton gradient across the membrane, which is used by ATP synthase to generate ATP.

Question 4

According to the fourth image, what is the total theoretical ATP yield from one molecule of glucose during aerobic respiration in eukaryotes?

Accepted Answer

$$38$$

Question 5

Referencing the fifth image, which fermentation product is associated with Saccharomyces?

Accepted Answer

CO₂ and ethanol

Question 6

Based on the sixth image, what is the connection between gut microbiota and nonalcoholic fatty liver disease (NAFLD)?

Accepted Answer

High-alcohol-producing strains of Klebsiella pneumoniae in the gut can lead to NAFLD by producing alcohol from dietary sugars.

Question 7

In the seventh image, what is the significance of the interaction between Streptococcus gordonii and Fusobacterium nucleatum?

Accepted Answer

Streptococcus gordonii activates Fusobacterium nucleatum to produce methyl mercaptan, contributing to bad breath.

Question 8

The eighth image depicts photophosphorylation. What is the role of light in this process?

Accepted Answer

Light excites electrons in pigments, initiating electron flow that generates a proton gradient for ATP synthesis.

Question 9

According to the ninth image, what is the main strategy used by oil-eating microbes to clean up oil spills?

Accepted Answer

They metabolize hydrocarbons in oil, converting them into water and carbon dioxide.

Question 10

In the tenth image, what is the significance of the enzymes PETase and MHETase produced by I. sakaiensis?

Accepted Answer

They catalyze the breakdown of PET plastic into monomers that can be metabolized by the bacterium.

Question 11

Based on the eleventh image, how can dietary DMB (from red wine and olive oil) affect cardiovascular health?

Accepted Answer

DMB inhibits microbial TMA lyase, reducing the production of TMA and thus lowering the risk of atherosclerosis.

Question 12

In the twelfth image, why might some Parkinson’s disease patients require higher doses of L-dopa?

Accepted Answer

Gut bacteria convert L-dopa to dopamine in the intestine, preventing it from reaching the brain.

Question 13

Which of the following statements about substrate-level phosphorylation is correct?

Accepted Answer

It involves the direct transfer of a phosphate group from a high-energy intermediate to ADP, forming ATP.

Question 14

Which pathway is unique to some gram-negative bacteria and produces one NADPH, one NADH, and one ATP per glucose?

Accepted Answer

Entner-Doudoroff pathway

Question 15

What is the main function of the pentose phosphate pathway in bacteria?

Accepted Answer

To generate NADPH and ribose-5-phosphate for biosynthesis.

Question 16

Which of the following best describes a chemoorganoheterotroph?

Accepted Answer

An organism that obtains both energy and carbon from organic compounds.

Question 17

During aerobic respiration, what is the sequence of major metabolic steps from glucose to ATP production?

Accepted Answer

Glycolysis → Pyruvate oxidation → Krebs cycle → Electron transport system

Question 18

Which of the following is a key advantage of fermentation for microorganisms?

Accepted Answer

It allows ATP production in the absence of oxygen or an electron transport chain.

Question 19

What is the main role of NAD⁺ in cellular metabolism?

Accepted Answer

It acts as an electron carrier, accepting electrons during catabolic reactions to become NADH.

Slides #5 - Microbial Metabolism: Pathways, Energy Production, and the Human Microbiome

Guida di studio - Domande di pratica

Study guide - Flashcard