Cellular Respiration: Glycolysis Overview

Questions and Answers

What is the main product of glycolysis?

Glucose

ATP

Pyruvate (correct)

NADH

Glycolysis occurs in the mitochondria.

False

During glycolysis, how many ATP molecules are consumed?

The process that occurs if there is no oxygen present after glycolysis is called ______.

fermentation Signup and view all the answers

What is produced at the end of pyruvate oxidation?

Acetyl-CoA Signup and view all the answers

The Krebs Cycle requires oxygen to produce CO2.

True Signup and view all the answers

What molecule do the acetyl groups bind to during pyruvate oxidation?

Coenzyme A Signup and view all the answers

The end result of glycolysis includes 2 NADH and ______ Pyruvate.

2 Signup and view all the answers

Match the following stages of cellular respiration with their main output:

Glycolysis = 2 ATP, 2 NADH, 2 Pyruvate Pyruvate Oxidation = 2 CO2, 2 NADH, 2 Acetyl-CoA Krebs Cycle = NADH, FADH2, ATP Fermentation = Lactate or Ethanol Signup and view all the answers

How many times must the Krebs Cycle occur for one glucose molecule?

2 Signup and view all the answers

Study Notes

Glycolysis (Cytoplasm)

Breakdown of glucose (6-carbon sugar) into 2 molecules of pyruvate.
2 ATP consumed to convert glucose into fructose.
Fructose splits into G3P, which is oxidized; electrons transferred to NAD+ forming 2 NADH.
Final conversion of G3P to pyruvate produces a net gain of 2 ATP.
NET result: 2 ATP, 2 NADH, and 2 pyruvate molecules.
In absence of oxygen, pyruvate undergoes fermentation; in presence of oxygen, it shifts to the mitochondria.

Pyruvate Oxidation (Matrix)

Pyruvate moves from cytoplasm to mitochondrial matrix.
Each pyruvate loses one carbon, resulting in 2-carbon acetyl group.
Reduction of NAD+ to NADH occurs during carbon loss.
Acetyl group binds to coenzyme A, forming acetyl-CoA.
End results: 2 CO2, 2 NADH, and 2 acetyl-CoA produced.

The Krebs Cycle (Inner Membrane)

Requires oxygen and results in CO2 production.
Acetyl-CoA combines with a 4-carbon molecule to form a 6-carbon compound.
6-carbon compound loses a carbon as CO2, generating NADH from NAD+.
Five-carbon molecule then releases another CO2, producing additional NADH and ATP.
Four-carbon molecule undergoes transformations to release electrons, forming 1 FADH2 and another NADH.
Cycle restarts when four-carbon molecule binds to new acetyl-CoA; cycle must occur twice per glucose to process 2 pyruvate.

Description

This quiz covers the glycolysis stage of cellular respiration, detailing the breakdown of glucose into pyruvate in the cytoplasm. Participants will explore the processes involved, including the conversion of glucose to fructose and the production of ATP and NADH. Test your understanding of this essential metabolic pathway!