AP BIO CRAM UNIT 3

Cellular Energetics

Induced fit

Active site slightly changes to bind more effectively to the substrate

Energy Coupling

Use of an exergonic process to driven an endergonic one.

Thylakoid

membrane discs inside chloroplasts where light-dependent reactions occur.

Stroma

Fluid-filled space surrounding the thylakoid discs where the Calvin Cycle (light independent) reactions occur

Photolysis

Process of splitting water molecules using light energy to provide electrons for Photosystem II (O2 byproduct)

Glycolysis

Anaerobic breakdown of glucose into two pyruvate molecules, in cytosol

Chemiosmosis

As each hydrogen ion flows down the ATP synthase, ADP is phosphorylated into ATP

Oxidative phosphorylation

combination of ETC and chemiosmosis

Final electron acceptor

oxygen

Fermentation

Anaerobic, allows glycolysis to continue, regenerates NAD+ from NADH in the absence of oxygen

Glycolysis produces…

2 ATP (net total)

NAD+ regeneration includes

Conversion of 2 pyruvate to 2 lactate,

Krebs Cycle products are

CO₂, NADH from NAD+, FADH₂ from FAD

Electron Transport Chain

Occurs in the inner mitochondrial membrane (cristae), chops off hydrogen ions, pumps into cell through proton pumps, as 2H+ travels back down ATP synthesis enzyem, ADP is converted to ATP.

Photosynthesis reactants

Water, light energy,

Photosynthesis products

ATP, NADPH, O₂ as byproduct

Photosynthesis

Light hits chlorophyll, excites electrons to a higher energy state. Electron ETC makes ATP, at end NADP+ picks up electrons and proton, becomes NADPH. Photolysis occurs to replace lost electrons.

Calvin Cycle

In stroma, RuBisCo enzyme attaches to carbon dioxide and RuBP, making 3=PGA. ATP + NADPH used to reduce 3-PGA into G3P, sugar monomer of glucose. Most of G3P recycled.