7 Microbial Metabolism_240710_135857

microbiology

What is metabolism?

All chemical reactions in an organism.

What are the two classifications of chemical reactions in metabolism?

Catabolic and anabolic.

What is catabolism?

The process of breaking down compounds, releasing energy overall.

What type of reactions are primarily involved in catabolism?

Usually hydrolytic reactions.

What is anabolism?

The process of building compounds, requiring energy overall.

What is the principal energy-carrying molecule in cells?

Adenosine Triphosphate (ATP).

How is ATP formed from ADP?

ADP is phosphorylated in the reaction: ADP + Pi + Energy → ATP.

What happens during ATP hydrolysis?

ATP is broken down into ADP and inorganic phosphate, releasing energy.

What is activation energy?

The energy required for a chemical reaction to occur.

What is an enzyme?

A biological catalyst that speeds up chemical reactions without being altered.

What is an apoenzyme?

The protein portion of an enzyme that must be activated by a cofactor.

What is feedback inhibition?

A mechanism that stops a cell from making more product than it needs.

Define competitive inhibitors.

Molecules that bind to an enzyme’s active site, preventing substrate binding.

What is Streptococcus pyogenes?

A Gram-positive cocci bacterium that can cause strep throat, scarlet fever, and more.

What is the net yield of NADH from glycolysis?

2 NADH.

What are the three main stages of aerobic respiration?

Glycolysis, Krebs Cycle, and Electron Transport Chain.

What is the purpose of chemiosmosis in aerobic respiration?

To generate ATP by using the proton gradient established by the electron transport chain.

What is the final electron acceptor in aerobic respiration?

Oxygen.

How many ATP molecules can prokaryotes produce from aerobic respiration?

38 ATP.

What is lactic acid fermentation?

The process where 2 pyruvic acid are converted to 2 lactic acid, producing 2 ATP.

What type of fermentation is performed by yeast?

Alcohol fermentation, where 2 pyruvic acid are converted to 2 ethanol.

What is the overall function of the Krebs cycle?

To release energy stored in acetyl CoA step by step.

What happens during the linking step before entering the Krebs Cycle?

Pyruvic acid is converted to acetyl CoA, losing one carbon as CO2.

What are the electron carriers used in cellular energy processes?

NAD, NADP, and FAD.

What is substrate-level phosphorylation?

A method of forming ATP by directly transferring a phosphate group to ADP from a substrate.

What causes enzyme denaturation?

Environmental conditions that change the shape of the enzyme’s active site.

What is the function of a catalyst?

To speed up chemical reactions without being altered by the reaction.

How are anabolic reactions coupled with ATP?

They require energy from ATP hydrolysis.

What is the overall difference between aerobic and anaerobic respiration?

Aerobic respiration uses oxygen as the final electron acceptor; anaerobic respiration uses a different molecule.

What are the products of fermentation?

Lactic acid or alcohol, depending on the type of fermentation.