Lecture 8: Cellular Respiration and Fermentation

Flashcards covering key vocabulary terms and concepts related to cellular respiration and fermentation, for an upcoming exam.

Chloroplasts

Organelles in producers that make organic molecules via photosynthesis.

Mitochondria

Organelles that break down organic molecules to produce ATP.

ATP

Adenosine triphosphate, the energy currency of the cell.

Cellular respiration

The process by which glucose and other organic molecules are broken down to produce ATP.

Electron carriers

Molecules that transfer electrons during cellular respiration, such as NAD+ and FAD.

Glycolysis

The first step in cellular respiration where glucose is broken down into pyruvate.

Citric Acid Cycle (Krebs Cycle)

A series of reactions that further break down acetyl CoA to produce ATP and electron carriers.

Oxidative phosphorylation

The final stage of cellular respiration where ATP is produced through the electron transport chain and chemiosmosis.

Anaerobic respiration

Respiration that occurs without oxygen, using alternative electron acceptors.

Fermentation

A metabolic process that occurs in the absence of oxygen, producing ATP and regenerating NAD+.

Proton motive force

The electrochemical gradient generated by the electron transport chain that drives ATP synthesis.

Substrate-level phosphorylation

The direct transfer of a phosphate group to ADP to form ATP during glycolysis and the Krebs cycle.

Pyruvate

The end product of glycolysis that can be further processed in aerobic or anaerobic conditions.

Acetyl CoA

The molecule that enters the citric acid cycle after pyruvate oxidation.

Lactic acid fermentation

A type of fermentation where pyruvate is reduced to lactic acid, regenerating NAD+.

Alcohol fermentation

A type of fermentation where pyruvate is converted into ethanol and carbon dioxide.

NAD+

An electron carrier that is reduced to NADH during cellular respiration.

FAD+

Another electron carrier that is reduced to FADH2 during cellular respiration.

Electron transport chain

A series of complexes that transfer electrons from electron carriers to oxygen.

Chemiosmosis

The movement of protons across a membrane to generate ATP.

Oxidative phosphorylation

The process of generating ATP through the electron transport chain and chemiosmosis.

Oxaloacetate

A four-carbon molecule that combines with acetyl CoA to form citrate in the citric acid cycle.

Citrate

The six-carbon compound formed from acetyl CoA and oxaloacetate in the citric acid cycle.

Acetaldehyde

The intermediate formed during alcohol fermentation, which is converted into ethanol.

Fermentation products

The end products of fermentation, such as lactic acid and ethanol.

NADH

The reduced form of NAD+, an important electron carrier in cellular respiration.

ATP Synthase

An enzyme that synthesizes ATP by using the proton gradient.

Intermembrane space

The space between the inner and outer membranes of mitochondria.

Cristae

The folds of the inner mitochondrial membrane that increase the surface area for ATP production.

Matrix

The innermost compartment of the mitochondria where the citric acid cycle occurs.

Gymnosperms

Plants that produce seeds not enclosed in chambers.

Angiosperms

Flowering plants that produce seeds within a fruit.

Fermentation pathway

The metabolic process that converts sugar to acids, gases, or alcohol.

Alcoholic fermentation

The process by which sugars are converted into alcohol and carbon dioxide.

Lactate

A three-carbon compound produced during lactic acid fermentation.

Fermentation types

Includes lactic acid fermentation and alcoholic fermentation.

Endergonic reaction

A reaction that absorbs energy.

Exergonic reaction

A reaction that releases energy.

Krebs Cycle

Another name for the citric acid cycle, where Acetyl CoA is oxidized.

FADH2

The reduced form of FAD, which carries electrons to the electron transport chain.

Pyruvate oxidation

The conversion of pyruvate into acetyl CoA before entering the Krebs cycle.

ATP yield

The total amount of ATP produced during cellular respiration.

Anaerobic conditions

Conditions in which oxygen is not present.

Aerobic conditions

Conditions in which oxygen is present.

Energy investment phase

The first phase of glycolysis, where ATP is consumed.

Energy payoff phase

The final phase of glycolysis, where ATP and NADH are produced.

Oxygen's role

To act as the final electron acceptor in the electron transport chain.

Reduced forms

The forms of electron carriers after they gain electrons.

Oxidized forms

The forms of electron carriers before they gain electrons.

ATP production

The formation of ATP through substrate-level phosphorylation and oxidative phosphorylation.

Respiration components

Includes glycolysis, pyruvate oxidation, Krebs cycle, and oxidative phosphorylation.

Metabolic pathways

A series of reactions that lead to the conversion of substances.

Bioenergetics

The study of how energy flows through living organisms.

ATP hydrolysis

The process of breaking down ATP to release energy.

Glucose breakdown

Occurs through glycolysis, Krebs cycle, and oxidative phosphorylation.

Chemical energy

Energy stored in the bonds of chemical compounds.

Inorganic electron acceptors

Molecules other than oxygen used in anaerobic respiration.

Molecule types

Includes carbohydrates, fats, proteins, used in catabolic pathways.

Cellular metabolism

The sum of all chemical processes that occur within a cell.

Fermented foods

Products resulting from fermentation, like yogurt, cheese, bread.

Yeast fermentation

Used in baking and brewing industries to produce alcohol.

Fermentation efficiency

Is lower than aerobic respiration in terms of ATP yield.

Alcohol production

Involves converting sugars to ethanol during fermentation.

Proton gradient

A difference in proton concentration across a membrane that drives ATP synthesis.

Respiratory substrates

Substances utilized by cells to produce ATP through respiration.

Energy yield

The amount of usable energy produced during metabolic processes.

Acidic fermentation products

Include lactic acid produced during lactic fermentation.

Alkaline fermentation products

Include ethanol produced during alcoholic fermentation.

Human exercise metabolism

Utilizes both aerobic and anaerobic respiration based on oxygen availability.

Biological oxidation

The process of transferring electrons from substrates to oxygen or other molecules.