Cell Bioenergetics Review

A collection of flashcards covering key concepts in cell bioenergetics, including energy metabolism pathways, ATP synthesis, glycolysis, and metabolic regulation.

What is bioenergetics?

The capture, transformation, and use of energy by living systems.

Which pathways are involved in energy metabolism?

Catabolic pathways and anabolic pathways.

What is the main function of ATP, NADH, and FADH2?

They are activated carrier molecules that store energy released by metabolism.

What does Gibbs free energy (G) represent?

Energy that can be utilized to do work in a cell.

If the change in free energy (ΔG) is negative, what does that indicate?

The reaction is spontaneous and energy is released.

If ΔG is positive, what is required for the reaction to occur?

Energy input is required, and the reaction is not spontaneous.

What is glycolysis?

The breakdown of glucose through a series of steps to produce pyruvate and a net yield of ATP and NADH.

What is the net ATP yield in glycolysis per glucose molecule?

2 ATP per glucose molecule.

What happens to pyruvate in aerobic conditions?

Pyruvate is converted into acetyl CoA and enters the Krebs cycle.

In anaerobic conditions, what can pyruvate be converted to?

Lactic acid or ethanol and CO₂.

What is the role of the electron transport chain (ETC)?

To transfer electrons from NADH and FADH2 to oxygen, creating a proton gradient that drives ATP synthesis.

What is chemiosmosis?

The coupling of a proton gradient across a membrane to drive ATP synthesis.

What are the three mechanisms of ATP synthesis?

Photophosphorylation, oxidative phosphorylation, and substrate level phosphorylation.

What occurs during the Calvin cycle?

Carbon fixation where CO₂ is converted into organic sugars using ATP and NADPH.

Why is rubisco important in photosynthesis?

It catalyzes the reaction of CO₂ with RuBP, initiating the Calvin cycle.

What does feedback inhibition refer to in metabolic regulation?

The mechanism where the end product of a metabolic pathway inhibits an earlier step in the pathway.

How do cells regulate enzyme activity?

Through mechanisms such as allosteric regulation, covalent modification, and enzyme inhibition.