pyruvate

Aerobic respiration

Energy-producing metabolism that requires oxygen and occurs in mitochondria.

Two major stages of aerobic respiration

The TCA (Krebs) cycle and oxidative phosphorylation.

TCA cycle (kreb cycle)

A metabolic cycle that oxidizes acetyl-CoA to generate NADH, FADH₂, and ATP.

Oxidative phosphorylation (ETC)

A process that uses electron transport and a proton gradient to synthesize ATP.

What happens to pyruvate before entering the TCA cycle

Pyruvate is oxidized, producing 1 NADH, 1 CO₂, and acetyl-CoA

What electron carrier is produced during pyruvate oxidation

NADH

What is produced per pyruvate molecule

One NADH, one CO₂, and one acetyl-CoA

What is the first step of the TCA cycle

Acetyl-CoA combines with oxaloacetate to form Citrate

How many carbons are released as CO₂ during the TCA cycle

2 per acetyl-CoA

How many times does the TCA cycle run per glucose

Twice

What is the total yield for 1 glucose

4 ATP, 10 NADH, and 2 FADH₂

Where do NADH and FADH₂ go next

oxidative phosphorylation

Where does NADH enter the ETC

Complex I

Where does FADH₂ enter the ETC

Complex II

How many ATP are produced from NADH per glucose

About 25 Atp

How many ATP are produced from FADH₂ per glucose

About 3

What is the total ATP yield per glucose in aerobic respiration

About 32 ATP.

What are reactive oxygen species (ROS)

Highly reactive oxygen-containing molecules that can damage cellular components such as DNA, proteins, and lipids.

Name a reactive oxygen species

Superoxide (O₂-) )

Name a reactive nitrogen species

Nitric oxide

Why does aerobic metabolism generate ROS

Electron leakage occurs during respiration

How to mitigate oxidative stress

glutathione (GSH)

What molecule accepts the acetyl group from acetyl-CoA

Oxaloacetate

What is formed when acetyl-CoA combines with oxaloacetate

Citrate

What is the main purpose of the TCA cycle

To oxidize carbon and generate NADH and FADH₂

What are produced in the TCA cycle

NADH, FADH₂, and GTP (or ATP)

What happens to CO₂ during the TCA cycle

More CO₂ is generated as carbons are fully oxidized

What is produced per acetyl-CoA in the TCA cycle

3 NADH, 1 FADH₂, 1 ATP (or GTP), 2 CO₂

How many protons does one NADH move across the inner membrane

10 H⁺

How many protons does one FADH₂ move across the inner membrane

6 H⁺

ATP yield from glycolysis

2 ATP G

ATP yield from the TCA cycle

2 ATP Kreb