Lecture Notes on Cellular Respiration and Fermentation

This set of flashcards covers key concepts, terms, and processes related to cellular respiration and fermentation, including the various pathways, mechanisms, and their regulatory aspects.

Cellular Respiration

A set of metabolic reactions that uses electrons from high-energy molecules to make ATP.

ATP

Adenosine triphosphate, the energy currency of the cell that provides energy for cellular work.

Glycolysis

The process by which glucose is broken down into pyruvate, producing ATP and NADH.

Pyruvate Processing

The conversion of pyruvate into acetyl CoA, occurring in the mitochondria.

Citric Acid Cycle

Also known as the Krebs cycle, where acetyl CoA is oxidized to CO2, generating NADH and FADH2.

Electron Transport Chain (ETC)

A series of protein complexes that transfer electrons, releasing energy to pump protons and produce ATP.

Chemiosmosis

The process by which ATP is produced using the proton gradient generated by the electron transport chain.

Fermentation

A metabolic pathway that regenerates NAD+ from NADH, allowing glycolysis to continue in the absence of oxygen.

NADH

Nicotinamide adenine dinucleotide, an electron carrier that stores energy during cellular respiration.

FADH2

Flavin adenine dinucleotide, another electron carrier produced during the citric acid cycle.

Substrate-level Phosphorylation

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

Oxidative Phosphorylation

The production of ATP using the energy derived from the electron transport chain and chemiosmosis.

Homeostasis

The maintenance of a stable internal environment within a cell or organism.

High-energy Molecules

Compounds like glucose that provide the energy needed for cellular processes.

ATP Hydrolysis

The reaction that breaks ATP into ADP and inorganic phosphate, releasing energy.

Feedback Inhibition

A regulatory mechanism in which the accumulation of a product inhibits its own production.

Acetyl CoA

A two-carbon molecule that enters the citric acid cycle after pyruvate processing.

Proton Gradient

A difference in proton concentration across a membrane, used to drive ATP synthesis.

Glycogen

A stored form of glucose, primarily found in the liver and muscle cells.

Alcohol Fermentation

A fermentation process used by yeast, converting pyruvate into ethanol and CO2.

Lactic Acid Fermentation

A fermentation process that converts pyruvate into lactate, primarily in muscle cells during low oxygen.

Metabolic Pathways

Series of biochemical reactions that modify substrates through enzyme-catalyzed reactions.

ATP Synthase

An enzyme that synthesizes ATP from ADP and inorganic phosphate during chemiosmosis.

Electrons

Subatomic particles that are transferred through the electron transport chain, helping to create a proton gradient.

Reactive Oxygen Species (ROS)

Highly reactive molecules formed during metabolism that can cause cellular damage.

Phosphorylation

The addition of a phosphate group to a molecule, usually to activate or deactivate its function.

Oxygen

The final electron acceptor in aerobic respiration, crucial for efficient ATP production.

Anaerobic Respiration

A form of respiration that does not use oxygen and relies on different electron acceptors.

Prokaryotes

Single-celled organisms that lack a nucleus; some can perform anaerobic respiration.

Eukaryotes

Organisms whose cells have a nucleus; perform aerobic respiration.

Mitochondria

Organelles known as the powerhouse of the cell, where aerobic respiration takes place.

Cristae

The folds of the inner mitochondrial membrane where the electron transport chain is located.

Intermembrane Space

The space between the inner and outer membranes of mitochondria where protons accumulate.

Matrix

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

Acetaldehyde

An intermediate in alcohol fermentation, derived from pyruvate.

Fermentation Pathways

Various metabolic pathways that regenerate NAD+ in the absence of oxygen.

ATP Yield

The amount of ATP produced during cellular respiration; approximately 29 ATP per glucose.

Regulation

The mechanisms that control the rates of metabolic pathways in cells.

Chemical Energy

Energy stored in the bonds of chemical compounds, used to perform work in biological systems.

ATP Production

The process of generating ATP from ADP and inorganic phosphate through various metabolic pathways.

Pyruvate Dehydrogenase

A complex enzyme involved in converting pyruvate to acetyl CoA.

Phosphofructokinase

An enzyme that catalyzes a key regulatory step in glycolysis.

Hydrolysis

The chemical breakdown of a compound due to reaction with water.

Glucose Oxidation

The process of breaking down glucose to release energy during cellular respiration.

Redox Reactions

Chemical reactions involving the reduction and oxidation of molecules.

Cyclic Pathway

A series of reactions that regenerate starting materials, such as in the citric acid cycle.

Psychrophiles

Organisms that thrive in extremely cold environments; often rely on fermentation.

Facultative Anaerobes

Organisms that can switch between aerobic respiration and fermentation based on oxygen availability.

Conformational Change

A change in the shape of a protein that can affect its function, often due to binding of a substrate.

Glycolytic Pathway

The sequence of reactions that convert glucose into pyruvate and produce ATP.

Ion Channels

Proteins that allow ions to flow across membranes, contributing to electrochemical gradients.

Phosphorylation Cascade

A series of chemical reactions during which one enzyme activates another by phosphorylation.

Cellular Metabolism

The total of all chemical reactions occurring within a cell.

Enzyme Complex

A grouping of several proteins that work together to catalyze a specific metabolic reaction.

Cori Cycle

The cycle in which lactate produced in muscles is converted back to glucose in the liver.

Cellular Respriration

A set of metabolic reactions that converts biochemical energy from nutrients into ATP.

Mitochondrial Membrane

The double membrane surrounding mitochondria, crucial for ATP production.

ATPase

An enzyme that breaks down ATP, releasing energy for cellular processes.

Oxaloacetate

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

Enzyme Activity

The rate at which an enzyme catalyzes a reaction, influenced by various factors including substrate concentration and pH.

Acetylation

The addition of an acetyl group to a molecule, which can modify the activity of proteins.

Simpson's Paradox

A phenomenon where a trend appears in several different groups of data but disappears or reverses when these groups are combined.

Crucial Chemical Reactions

The essential biochemical processes that sustain life, involving the transformation of substrates into products.

High-energy Compounds

Molecules that store energy, including ATP, NADH, and FADH2.

Energy Conservation

The principle of saving energy by optimizing metabolic pathways in response to environmental conditions.

Amino Acid Degradation

The breakdown of amino acids, typically to feed into central metabolic pathways.

Biological Electron Transport

The movement of electrons through a series of proteins or other molecules that ultimately contributes to ATP production.

Sugar Metabolization

The biochemical processes involved in breaking down sugars for energy.

Temperature Effects on Metabolism

The influence of temperature on the rate of metabolic processes, affecting enzyme activity and efficiency.

Nucleotide Synthesis

The process by which nucleotides are created, often from intermediates in cellular respiration.