Photosynthesis and Cellular Respiration Overview

These flashcards cover key concepts and terms related to photosynthesis, cellular respiration, and energy transformations.

ATP (Adenosine Triphosphate)

An energy storage molecule that provides energy for cellular processes.

Hydrolysis

The process of breaking down ATP into ADP and a phosphate group, releasing energy.

Metabolism

The sum of all chemical reactions in an organism, including anabolic and catabolic reactions.

Anabolic Reactions

Processes that build larger molecules from smaller ones, requiring energy.

Catabolic Reactions

Processes that break down molecules into smaller units, releasing energy.

Kinetic Energy

Energy in motion.

Potential Energy

Stored energy that has the potential to do work.

Law of Conservation of Mass

Mass of reactants = mass of products, matter is recycled.

Aerobic Respiration

Cellular respiration that requires oxygen to break down glucose.

Anaerobic Respiration

Cellular respiration that does not require oxygen, relies on alternative processes.

Glycolysis

The first step in cellular respiration, where glucose is converted into pyruvate with a net gain of 2 ATP.

NADH

A coenzyme that transports electrons and helps in the production of ATP.

Krebs Cycle

A series of reactions that occur in the mitochondrial matrix, producing NADH and ATP through the breakdown of acetyl groups.

Electron Transport Chain

A series of proteins in the inner mitochondrial membrane that transfer electrons to produce ATP using oxygen.

Fermentation

A metabolic process that converts sugars to acids, gases, or alcohol in the absence of oxygen.

Alcoholic Fermentation

The process where pyruvate is converted into alcohol and carbon dioxide, generating NAD+ for glycolysis.

Lactic Acid Fermentation

A process used by muscle cells during oxygen debt, converting pyruvate into lactate.

Sequence of ATP Hydrolysis

1. A water molecule is added to an ATP molecule. 2. The high-energy chemical bond of the third phosphate group is broken. 3. Energy is released for cellular work as ATP becomes ADP and an inorganic phosphate (P_i).

Metabolic Reaction Types

1. Anabolic Reactions: These processes use energy to assemble larger, complex molecules from smaller units. 2. Catabolic Reactions: These processes break down complex molecules into smaller units, releasing energy to be stored as ATP.

Conversion of Kinetic and Potential Energy

1. Potential Energy: Stored in the chemical bonds of glucose and ATP molecules. 2. Kinetic Energy: Released during chemical reactions, allowing for cellular movement and biological work.

Four Main Steps of Glycolysis

1. Investment: 2 ATP molecules are used to activate glucose. 2. Cleavage: The 6-carbon glucose is split into two 3-carbon sugars. 3. Oxidation: Phosphates are added and NAD^+ is reduced to NADH. 4. Payoff: 4 ATP are produced, resulting in a net gain of 2 ATP and 2 pyruvate molecules.

Detailed Steps of the Krebs Cycle

1. Activation: Pyruvate is oxidized into Acetyl-CoA as it enters the mitochondria. 2. Cycle Entry: Acetyl-CoA combines with a 4-carbon molecule to form citrate. 3. Gas Release: Carbon atoms are released as CO2. 4. Energy Capture: Harvests high-energy electrons to form 3 NADH and 1 FADH2, plus 1 ATP per turn.

The Mechanism of the Electron Transport Chain (ETC)

1. Electron Delivery: NADH and FADH2 donate electrons to the inner mitochondrial membrane. 2. Proton Pumping: Electron energy pumps H^+ ions into the intermembrane space to create a gradient. 3. ATP Synthesis: H^+ flows back through ATP synthase, driving the production of ATP. 4. Water Formation: Oxygen accepts the spent electrons and H^+ to form H2O.

Process of Lactic Acid Fermentation

1. Glycolysis: Glucose is broken down into pyruvate and NADH. 2. Electron Transfer: NADH transfers electrons directly to pyruvate. 3. Regeneration: Pyruvate is reduced to lactate, which restores the NAD^+ supply needed for glycolysis to continue.

Steps of Alcoholic Fermentation

1. Glycolysis: Glucose is converted into pyruvate and NADH. 2. Decarboxylation: Pyruvate is converted into a 2-carbon compound with the release of CO_2. 3. Ethanol Production: NADH reduces the 2-carbon compound to ethanol, regenerating NAD^+ for the cell.