Bio 006 - Cell Respiration II & Fermentation

Pyruvate Kinase

Enzyme that converts ADP to ATP and glucose to pyruvate.

Pyruvate Dehydrogenase

Enzyme that makes Pyruvate then adds it to Coenzyme A to Acetyl CoA + CO2 and NAD to NADH.

Oxidative Phosphorylation

Uses the enzyme ATP synthase, which synthesizes ATP using energy from redox reactions.

ATP Synthase

An integral protein that sits in the inner membrane of mitochondria and is powered by H+ (hydrogen ions).

H+ Storage

For ATP Synthase to function, a lot of H+ must be stored in the inner-membrane space.

NADH & FADH2

• Molecules involved in cell respiration that provide H+ needed to power ATP synthase.

• Energy carriers

Electron Transport Chain

A series of integral proteins in the inner-membrane that pass along the H+ (electrons) of NADH & FADH2.

Active Transport

The process used by the electron transport chain to push H+ into the inner-membrane space.

Chemiosmosis

• Powers ATP synthase

• The natural movement of ions across a membrane moving down their concentration gradient.

• Opposite of active transport.

Substrate-Level Phosphorylation

A process that generates ATP directly in the Citric Acid Cycle using mitochondrial enzymes.

Integral Proteins

Proteins that assist in the active transport of pyruvate across mitochondrial membranes.

Mitochondrial Matrix

The cytoplasm of the mitochondria where Pyruvate Oxidation and the Citric Acid Cycle occur.

Acetyl CoA

A product of Pyruvate Oxidation that enters the Citric Acid Cycle.

CO2 Production

A significant output of both Pyruvate Oxidation and the Citric Acid Cycle.

NADH Production

A key output of Glycolysis, Pyruvate Oxidation, and the Citric Acid Cycle.

FADH2 Production

Generated during the Citric Acid Cycle and used in oxidative phosphorylation.

Energy Source for ATP Synthase

The energy required for ATP Synthase comes from the redox reactions of NADH and FADH2.

ATP Yield

The total ATP produced from Glycolysis, Citric Acid Cycle, and Oxidative Phosphorylation combined.

Redox Reactions

Chemical reactions that involve the transfer of electrons, crucial for oxidative phosphorylation.

Chemiosmosis

The natural movements of ions across a membrane moving down their concentration gradient.

ATP synthase

The enzyme that is powered by chemiosmosis to synthesize ATP.

Oxidative Phosphorylation

The stage of cellular respiration that occurs across the inner membrane and produces 26 or 28 ATP.

Fermentation

A form of respiration that continues the process of glycolysis to generate ATP without oxygen.

Anaerobic Respiration

Respiration that occurs when oxygen isn't available (fermentation)

Glycolysis

The first stage of cell respiration that occurs outside the mitochondria in the cytoplasm, with an input of glucose and NAD, producing pyruvate, NADH, and H2O, yielding 2 ATP.

Substrate-level phosphorylation

A method of generating ATP during glycolysis and fermentation.

Lactic Acid Fermentation

A process where hydrogens from NADH are added to pyruvate to form lactic acid, allowing glycolysis to continue.

Alcoholic Fermentation

• A process where pyruvate is broken down to acetaldehyde and CO2, and hydrogens are added to acetaldehyde to form ethanol.

• Happens in the cytoplasm

• Usually makes food

Glucose and NAD

Input of Glycolysis

Pyruvate, NADH, and H2O

Output of Glycolysis

2

ATP yield of Glycolysis

Regenerating NAD

The process required to repeat glycolysis, which involves oxidizing NADH back to NAD.

Pyruvate

The output of glycolysis that can be used in fermentation.

Ethanol, CO2 , NAD

The output of alcoholic fermentation.

Lactic Acid, NAD

The output of lactic acid fermentation.

Pyruvate,NADH

The input of alcoholic fermentation.

Citric Acid Cycle

A stage of aerobic respiration that requires oxygen.

NADH

An electron carrier that is oxidized back to NAD during fermentation.

Oxygen in Aerobic Respiration

Required for aerobic respiration to occur.

Fermentation vs Aerobic Respiration

Fermentation does not require oxygen, whereas aerobic respiration does.

Fermentation in Humans

Used during intense exercise, leading to muscle soreness due to lactic acid.

Fermentation in Yeast

Used in baking and brewing, producing CO2 and ethanol.

GADPH

Enzyme that converts ADP to ATP and NAD to NADH.

Pyruvate,NADH

The input of lactic acid fermentation.