AP BIO Unit 3

What is cellular respiration?

Enzyme-catalyzed reactions that capture energy from biological molecules to synthesize ATP.

Where does glycolysis occur?

Cytosol

What is the starting material for glycolysis?

Glucose

What are the net products of glycolysis?

2 pyruvate, 2 NADH, and 2 ATP

What is fermentation's purpose?

Regenerates NAD+ so glycolysis can continue without oxygen.

What are fermentation products?

Organic molecules such as lactic acid or alcohol.

Where does the Krebs cycle occur?

Mitochondrial matrix

What enters the Krebs cycle?

Acetyl-CoA

What are Krebs cycle products per acetyl-CoA?

3 NADH, 1 FADH2, 1 ATP, and 2 CO2

Where does oxidative phosphorylation occur?

Mitochondrial inner membrane (cristae)

What powers oxidative phosphorylation?

Electrons from NADH and FADH2

What are the two parts of oxidative phosphorylation?

Electron transport chain and chemiosmosis

What is the final electron acceptor in cellular respiration?

Oxygen (O2)

Where are protons pumped during cellular respiration ETC?

Into the mitochondrial intermembrane space

What does chemiosmosis do?

ATP synthase uses the proton gradient to synthesize ATP.

What is photosynthesis?

Reactions using CO2, H2O, and light energy to produce carbohydrates and O2.

Where do the light reactions occur?

Thylakoid membranes (grana)

What pigment is found in photosystems?

Chlorophyll a

What are the starting materials for light reactions?

Water (electrons) and photons (energy)

What are the products of light reactions?

ATP and NADPH

Where are protons pumped during photosynthesis ETC?

Into the thylakoid space (lumen)

What does linear electron flow use?

Photosystem II and Photosystem I

What does linear electron flow produce?

ATP and NADPH

What does cyclic electron flow use?

Photosystem I only

What does cyclic electron flow produce?

ATP only

Where does the Calvin cycle occur?

Stroma

What enters the Calvin cycle to make one G3P?

3 CO2, 9 ATP, and 6 NADPH

What is the product of the Calvin cycle?

G3P (glyceraldehyde-3-phosphate)

What is the role of the Calvin cycle?

Fixes carbon and uses ATP and NADPH to produce G3P.

Where did photosynthesis first evolve?

Prokaryotes

Which organisms helped oxygenate Earth's atmosphere?

Cyanobacteria through photosynthesis

What did prokaryotic photosynthesis provide?

The foundation for eukaryotic photosynthesis.