CR Flashcards

What is the overall equation for cellular respiration?

C₆H₁₂O₆ + 6O₂ → 6H₂O + 6CO₂ + ATP (energy)

 What type of respiration uses oxygen?

Aerobic respiration

 What are the four main steps of cellular respiration (in order)?

 1. Glycolysis

2. Pyruvate Oxidation

3. Citric Acid (Krebs) Cycle

4. Oxidative Phosphorylation (ETC)

What is the role of NAD⁺/NADH in respiration?

NAD⁺ picks up electrons (is reduced) to become NADH, which carries electrons to the ETC.

Where does glycolysis occur?

Cytoplasm

Does glycolysis require oxygen?

No, it’s anaerobic.

What happens to glucose in glycolysis?

1 glucose → 2 pyruvate

Net yield of glycolysis from 1 glucose?

2 ATP, 2 NADH, 2 pyruvate

How many ATP are invested and produced in glycolysis?

2 invested, 4 produced → net = 2 ATP

Where does pyruvate oxidation occur?

Mitochondria

What does each pyruvate become after oxidation?

1 acetyl-CoA + 1 NADH + CO₂

What is the total output from 2 pyruvates?

 2 acetyl-CoA, 2 NADH, 2 CO₂

What does 1 acetyl-CoA produce in the Krebs cycle?

3 NADH, 1 FADH₂, 1 ATP

 Since 1 glucose makes 2 acetyl-CoA, what’s the total per glucose?

6 NADH, 2 FADH₂, 2 ATP

What is the role of the Krebs cycle products?

NADH and FADH₂ carry electrons to the ETC for oxidative phosphorylation.

Where does oxidative phosphorylation occur? 

 Inner mitochondrial membrane

What do NADH and FADH₂ provide to the ETC?

High-energy electrons

What happens to hydrogen ions (H⁺) in the ETC?

Pumped into inter membrane space → create a gradient

How is ATP made from this gradient?

H⁺ flows back through ATP synthase → ADP + Pi → ATP

What analogy is used for how ATP synthase works?

Like a dam: water pressure drives turbines, H⁺ drives ATP synthase

How much ATP is made from 1 NADH?

About 2.5 ATP

How much ATP is made from 1 FADH₂?

About 1.5 ATP

What is the total ATP from cellular respiration (approximate)?

30 ATP per glucose