Free Practice Quiz Question List

5 Microbial Metabolism Online Quiz Questions

Use this free practice quiz with 20 questions to review 5 Microbial Metabolism, test your knowledge, and prepare for your next test or exam.

20 questions

Choose one

1 point

A microbe uses light as its energy source and carbon dioxide as its carbon source. Which description best classifies it?

A
It uses chemical reactions for energy and organic compounds for carbon.
B
It uses light for energy and carbon dioxide for carbon.
C
It uses light for energy and organic compounds for carbon.
D
It uses chemical reactions for energy and carbon dioxide for carbon.

Choose one

1 point

A microorganism transfers electrons through an electron transport chain to nitrate rather than oxygen. Which pathway is it using?

A
Fermentation, because it uses an external electron acceptor.
B
Aerobic respiration, because it uses an electron transport chain.
C
Anaerobic respiration, because it uses an electron transport chain and nitrate as the terminal electron acceptor.
D
Photosynthesis, because nitrate accepts electrons.

Choose one

1 point

A cell has enough of a pathway’s end product, so that product inhibits an enzyme acting earlier in the pathway. What regulatory mechanism is occurring?

A
Feedback inhibition: the pathway’s end product inhibits an enzyme earlier in the pathway.
B
A substrate permanently binds to an enzyme and is consumed with it.
C
An enzyme converts ATP directly into an electron carrier.
D
A pathway’s first enzyme activates its end product.

Choose one

1 point

During respiration, an electron transport system establishes an electrochemical gradient across a membrane. How does that gradient support ATP production?

A
The gradient transfers phosphate directly from a substrate to ADP.
B
The gradient converts NADPH into NADP⁺ to make ATP.
C
The gradient causes the terminal electron acceptor to become ATP.
D
The gradient drives ions through ATP synthase, which makes ATP.

Choose one

1 point

A cell relies on glycolysis but lacks an electron transport chain. How does fermentation help glycolysis continue?

A
It supplies oxygen as the terminal electron acceptor.
B
It regenerates NAD⁺ needed for glycolysis.
C
It creates an electron transport chain in the cytoplasm.
D
It supplies carbon dioxide as the terminal electron acceptor.

Choose all

1 point

Select all statements that correctly describe the roles of these electron carriers.

A
NADH commonly carries electrons from catabolic reactions.
B
NADPH is the only carrier that transfers electrons between reactions.
C
FADH₂ commonly carries electrons from catabolic reactions.
D
NAD⁺ is used only to supply reducing power for biosynthesis.

Choose all

1 point

Select all statements that correctly distinguish oxygenic from anoxygenic photosynthesis.

A
Oxygenic photosynthesis uses water as an electron donor and releases oxygen.
B
Anoxygenic photosynthesis always uses water and releases oxygen.
C
Anoxygenic photosynthesis can use hydrogen sulfide and does not release oxygen.
D
Oxygenic photosynthesis uses hydrogen sulfide and does not release oxygen.

True or false

1 point

Fermentation can regenerate NAD⁺ for glycolysis without using an electron transport chain.

A
True
B
False

True or false

1 point

Biosynthesis can build cellular materials from precursors without requiring energy or reducing power.

A
True
B
False

Written response

1 point

What term describes the reactants that bind to an enzyme?

Written response

1 point

What are the building blocks that biosynthetic pathways use to assemble cellular materials called?

Fill in the blank

1 point

In aerobic respiration, serves as the terminal electron acceptor.

Fill in the blank

1 point

When an enzyme transfers a phosphate group directly to ADP to form ATP, the process is called .

Open ended

1 point

Explain how light energy supports ATP production and provides reducing power in microbial photosynthesis. Include the roles of electron flow and the membrane ion gradient.

Choose one

1 point

Which description correctly identifies oxygenic photosynthesis?

A
It uses hydrogen sulfide as an electron donor and releases oxygen.
B
It uses water as an electron donor and releases oxygen.
C
It uses carbon dioxide as an electron donor and releases oxygen.
D
It uses water as an electron donor but does not release oxygen.

Choose one

1 point

A fermenting cell needs glycolysis to continue. Which role of fermentation directly helps meet that need?

A
It regenerates NAD⁺ so glycolysis can continue.
B
It supplies an external terminal electron acceptor for an electron transport chain.
C
It converts NADPH into an electron acceptor for respiration.
D
It replaces glycolysis with oxidative phosphorylation.

True or false

1 point

In bacteria, respiratory and photosynthetic electron transport systems are typically located in the cell membrane. True or false?

A
True
B
False

Choose one

1 point

A cell's enzyme speeds up a reaction by binding its substrate. Which explanation best describes how the enzyme helps?

A
It raises the activation energy and is consumed as a reactant.
B
It supplies the cell's carbon source and becomes part of the product.
C
It lowers the activation energy and is not consumed by the reaction.
D
It transfers electrons to every substrate and is permanently altered.

Written response

1 point

A metabolic pathway's end product inhibits an enzyme that acts earlier in the same pathway. What is this regulatory mechanism called?

Written response

1 point

A microbe obtains energy from chemical reactions, uses inorganic electron donors, and builds cellular carbon from CO₂. What combined trophic term describes it?