BIO 205- Unit 3- Microbial Metabolism

Which of the following statements concerning reduction reactions is FALSE?

An electron acceptor becomes more positively charged.

Which of these statements is NOT true of the electron transport chain?

The electron transport chain in eukaryotes is located on the outer mitochondrial membrane.

Some bacteria use electrons carried by NADH to generate light instead of ATP.

True

When a cell forms an amino acid by adding an amine group derived from ammonia to a precursor metabolite, this process is called

amination.

Which of the following is a by-product of the catabolism of proteins?

ammonia

Reactions involving ligases are typically __________ reactions.

anabolic

The conversion of pyruvic acid to acetyl-CoA can be described as __________, because a molecule of CO2 is produced as a by-product.

decarboxylation

The conversion of amino acids to carbohydrates is an example of

gluconeogenesis.

Beta-oxidation of fatty acids produces a substrate of

the Krebs cycle.

Types of chlorophyll differ in the

wavelengths of light they absorb.

How many ATP molecules can be produced from the NADH generated by the catabolism of a molecule of glucose?

30

Which of the following molecules serves as the short-term recyclable energy supply for a cell?

ATP

Which of the following is a TRUE statement concerning the structure and function of enzymes?

After an enzyme has catalyzed a reaction, it resumes its original shape and can interact with a new substrate molecule.

Which of these is NOT true of an enzyme?

An enzyme raises the activation energy of a reaction.

Glycerol, necessary for the production of fats, can be derived from which of the following pathways?

Calvin-Benson cycle

ATP is made by substrate-level phosphorylation only during glycolysis.

False

In feedback inhibition pathways, the end-product of the pathway is usually an inhibitor of the last enzyme in the pathway.

False

The first compound formed in the Krebs cycle is oxaloacetic acid.

False

Which of the following statements concerning glycolysis is TRUE?

It both requires the input of ATP and produces ATP.

What is the major function of fermentation?

It regenerates NAD+ for glycolysis.

Which of the following pathways produces the most NADH and the least ATP?

Krebs cycle

Which of the following statements concerning cellular metabolism is FALSE?

Macromolecules are converted into cell structures via catabolism.

Which of the following is NOT a possible product of fermentation?

NADH

Which of the following is associated with the Calvin-Benson cycle?

RuBP

Which of the following statements concerning enzymes is FALSE?

They function best at 37°C.

Which of the following statements concerning the Krebs cycle is FALSE?

Two molecules of acetyl-CoA generate more ATP after two cycles than a single molecule of glucose at the end of glycolysis.

Put the following selected events of photosynthesis in the correct order: a. excitation of the reaction center chlorophyll b. fixation of CO2 c. photosystem I activity d. photosystem II activity ____________________.

a, d, c, b

Chemical reactions that can proceed toward either anabolism or catabolism are called

amphibolic.

Reactions catalyzed by transferases are

anabolic.

Hydrolysis reactions __________.

are catabolic

All of the following are associated with chemiosmosis EXCEPT

beta-oxidation.

Oxidoreductases participate in __________ reactions.

both anabolic and catabolic

Which of the following is (are) common to chemiosmosis and the light-dependent reactions of photosynthesis?

both electron transport and a proton gradient

Substrate-level phosphorylation occurs during the __________ stage(s) of glycolysis.

both energy-investment and energy-conservation

Pyruvic acid is a product of

both glycolysis and the Entner-Doudoroff pathway.

Which of the following can be the final electron receptor in anaerobic respiration in bacteria?

both nitrate and sulfate

Which of the following produces NADPH?

both the pentose phosphate and Entner-Doudoroff pathways

Enzymes known as lyases participate in __________ reactions.

catabolic

Hydrolases are generally involved in __________ reactions.

catabolic

The site of photosynthesis within a photosynthetic eukaryotic cell is the __________.

chloroplast

Sulfanilamide is an antimicrobial drug that mimics the shape of an important substrate for a particular bacterial enzyme, thereby inhibiting the enzyme. This type of inhibition is known as

competitive inhibition.

Which of the following is an INCORRECT association?

electron transport: acetyl-CoA

The production of NADH takes place during the __________ stage(s) of glycolysis.

energy-conservation

In which of the following stages of glycolysis is ATP made?

energy-conserving stage

Glucose enters glycolysis at the __________ stage(s).

energy-investment

Although glycolysis requires an input of ATP, this pathway results in a net gain of two ATP; therefore it is a(n) __________ pathway.

exergonic

Anabolic reactions that are essentially the reverse of beta-oxidation are important in the synthesis of which of the following?

fatty acids

If a cell reverses the process of beta-oxidation, which of the following molecules will it make?

fatty acids

In E. coli, the presence of isoleucine shuts down the enzymatic pathway that results in the synthesis of isoleucine. This is an example of _____.

feedback inhibition

Anabolic reactions may be characterized as

forming large molecules from smaller molecules.

What is the major product of the Calvin-Benson cycle that can then be used to form glucose?

glyceraldehyde 3-phosphate

In eukaryotic cells, all of the following processes occur in the mitochondrion EXCEPT __________.

glycolysis

Chlorophyll a is associated with all of the following photosynthetic organisms EXCEPT _____.

green bacteria

Which of the following types of carrier molecules is NOT found in electron transport chains?

hemoglobin

Where is the most ATP generated for most eukaryotic cells?

in the mitochondrial matrix

In photosynthetic bacteria, the light-dependent reaction __________.

involves an electron transport chain

Beta-oxidation __________.

is the process used by many bacteria to catabolize fatty acids

Which of the following is NOT a possible form of regulation of metabolism in bacteria?

isolating enzymes within membrane-bound regions, such as lysosomes

The intermediate known as DHAP is formed during the __________ stage(s) of glycolysis.

lysis

All of these statements are correct descriptions of bacterial metabolism EXCEPT __________.

metabolic processes can be isolated within certain parts of the cell, such as lysosomes

Reactions involving isomerases are

neither anabolic nor catabolic.

The Calvin-Benson cycle __________.

occurs in the cytoplasm of photosynthetic bacteria

What is the purpose of the light-dependent reactions of photosynthesis?

production of ATP and NADPH

All of the following are associated with the process of glycolysis EXCEPT __________.

production of NADPH.

Denaturation is most often a problem with which of the following?

proteins

All of the following are forms of oxidation EXCEPT

substrate-level phosphorylation.

The molecule that an enzyme acts upon is known as its

substrate.

Carbon dioxide is a by-product of which of the following?

the Krebs cycle

The acetyl-CoA generated from beta-oxidation can be used in which of the following pathways?

the Krebs cycle

Which of the following is NOT a catabolic pathway or reaction?

the conversion of glucose to starch

Membranes containing the photosystems necessary for photosynthesis are called

thylakoids.

Glycolysis __________.

transfers electrons from a substrate to NAD+

A "fishy" odor is usually due to the presence of which of the following molecules?

trimethylamine

The metabolic processes called fermentation

use an organic molecule as a final electron acceptor.

All of the following are aspects of a cell's ability to regulate its metabolism EXCEPT

use of the same coenzymes for anabolic and catabolic reactions that share substrate molecules.