Cellular Respiration Study Guide

Flashcards related to cellular respiration covering key concepts, processes, and terminology.

What is the primary purpose of cellular respiration?

To convert food into ATP by breaking down macromolecules.

What is the function of glycolysis in cellular respiration?

To break down glucose into two pyruvate molecules, producing a net gain of 2 ATP and 2 NADH.

Where does glycolysis occur?

In the cytoplasm of all living cells.

What are the main products of glycolysis per glucose molecule?

2 ATP and 2 NADH.

What happens to pyruvate under aerobic conditions?

It is converted into acetyl-CoA and enters the Krebs cycle.

What does the Krebs cycle produce per glucose molecule?

6 NADH, 2 FADH₂, and 2 ATP.

What is oxidative phosphorylation?

The process that generates most of the cell's ATP by using electrons from NADH and FADH₂ in the electron transport chain.

What is the difference between substrate-level phosphorylation and oxidative phosphorylation?

Substrate-level phosphorylation directly transfers a phosphate from a substrate to ADP to form ATP, while oxidative phosphorylation uses a proton gradient to produce ATP.

What are NADH and FADH₂ considered in cellular respiration?

They are electron carriers that transport high-energy electrons to the electron transport chain.

What is the role of ATP synthase in cellular respiration?

To synthesize ATP as protons flow back into the mitochondrial matrix.

What is fermentation and when does it occur?

Fermentation regenerates NAD⁺ by reducing pyruvate when oxygen is not available.

What is lactic acid fermentation?

A process where pyruvate is reduced to lactate to regenerate NAD⁺ in the absence of oxygen.

What is alcohol fermentation?

A process where pyruvate is converted into ethanol and CO₂, regenerating NAD⁺ under anaerobic conditions.

What is the net energy yield from glycolysis?

2 ATP and 2 NADH.

What is the fate of glucose in cellular respiration?

It gets broken down into pyruvate, which is then processed for energy production.

How many total acetyl-CoA molecules are produced from a triglyceride with three fatty acids, each with 10 carbons?

15 Acetyl-CoA molecules.

What does beta-oxidation produce from fatty acids?

Acetyl-CoA molecules that enter the Krebs cycle.

Why is the Krebs cycle important?

It fully oxidizes acetyl-CoA and generates high-energy electron carriers for ATP production.

What is the efficiency of ATP production from glucose?

Approximately 39% of glucose's energy is captured in ATP.

What compound acts as the final electron acceptor in the electron transport chain?

Oxygen, which combines with electrons to form water.