Overview of Cell Metabolism and Energy Pathways

Metabolism

Total chemical reactions in cells or body.

Enzyme Actions

Catalyze biochemical reactions in living organisms.

Catabolic Reactions

Break down molecules to release energy.

Anabolic Reactions

Build complex molecules from simpler ones.

Oxidation/Reduction Reactions

Chemical reactions involving electron transfer.

ATP Role

Energy currency of the cell for metabolism.

Metabolic Pathways

Series of chemical reactions in metabolism.

Glycolysis

Breakdown of glucose to pyruvate, producing ATP.

Citric Acid Cycle

Processes acetyl-CoA to produce energy carriers.

Oxidative Phosphorylation

Produces ATP using electron transport chain.

Catabolism

Degradation of biomolecules for energy production.

Synthesis

Formation of complex molecules from simpler ones.

Reversible Reactions

Reactions that can proceed in both directions.

Bidirectional Reaction

Reaction facilitated by enzyme in both directions.

Energy of Activation (EA)

Energy needed to initiate a chemical reaction.

Enzyme Features

Characteristics that define enzyme functionality.

Induced Fit

Enzyme shape changes to better fit substrate.

Apoenzyme

Protein part of enzyme without cofactor.

Coenzymes

Non-protein molecules aiding enzyme activity.

Factors Affecting Enzyme Activity

Conditions influencing enzyme efficiency and function.

Enzyme Regulation

Mechanisms controlling enzyme activity and function.

Substrate Concentration

Higher concentration increases enzyme activity.

Enzyme activity

Increases with temperature until denaturation occurs.

Denaturation

Loss of enzyme function due to high heat.

Molecular movement

Increased temperature enhances molecular collision likelihood.

pH range

Enzymes function optimally within specific pH levels.

Bidirectional reaction

Reaction can proceed in both forward and reverse.

Enzyme presence

Reactions require specific enzymes to occur.

Reactants vs. substrate

Reactants are not always interchangeable with substrates.

Sucrase substrate

Sucrose is the substrate for sucrase enzyme.

Sucrase products

Products of sucrase reaction are glucose and fructose.

Apoenzyme

Inactive enzyme without its cofactor.

Enzyme regulation

Enzymes are regulated by various biochemical mechanisms.

Catabolic reactions

Break down larger molecules, releasing energy.

Anabolic reactions

Build larger molecules, requiring energy input.

Exergonic reaction

Releases energy during the breakdown of molecules.

Endergonic reaction

Requires energy input to build larger molecules.

Redox reactions

Involve electron transfer between reactants.

Nutrient digestion

Common catabolic reactions for breaking down nutrients.

Monomer building blocks

Catabolic reactions provide amino acids and monosaccharides.

Energy capture

Cells capture energy released from catabolic reactions.

Macromolecule synthesis

Anabolic reactions create new macromolecules for cells.

Biological redox reactions

Often involve transfer of hydrogen or oxygen.

Reduction

Gain of electrons, increasing negative charge.

Oxidation

Loss of electrons, increasing positive charge.

Redox

Simultaneous reduction and oxidation reactions.

ATP

Adenosine triphosphate, energy currency of cells.

Phosphate group

Functional group that donates energy in ATP.

ATP hydrolysis

Exergonic reaction releasing energy from ATP.

Phosphorylation

Addition of a phosphate group to a molecule.

ADP

Adenosine diphosphate, product of ATP hydrolysis.

Pi

Inorganic phosphate, used to regenerate ATP.

Exergonic reactions

Reactions that release energy.

Endergonic reactions

Reactions that require energy input.

LEO goes GER

Mnemonic for remembering oxidation and reduction.

High energy group

Three phosphate groups in ATP structure.

Cellular work

Processes powered by ATP energy.

Energy regeneration

Conversion of ADP and Pi back to ATP.

Nucleotide

Building block of ATP, includes ribose.

Cellular processes

Biochemical activities requiring ATP energy.

Receptor molecule

Molecule that becomes phosphorylated for reactions.

Anabolic reaction

Building larger molecules from smaller ones.

Catabolic reaction

Breaking down molecules for energy.

Cellular Respiration

Process producing ATP using glucose and oxygen.

Catabolic Pathways

Energy-releasing pathways breaking down organic molecules.

Glycolysis

First step in cellular respiration occurring in cytoplasm.

Aerobic Pathways

Require oxygen, produce 36-38 ATP per glucose.

Anaerobic Pathways

Oxygen not required, produce 2 ATP per glucose.

ATP Production

Energy currency of the cell generated during respiration.

Redox Reactions

Reactions involving oxidation and reduction of molecules.

NAD+

Electron carrier that accepts electrons during respiration.

FAD

Another important electron carrier in cellular respiration.

Transition Step

Converts pyruvate into acetyl CoA for CAC.

Citric Acid Cycle

Completes oxidation of glucose, produces CO2 and ATP.

Acetyl CoA

Formed from acetate, enters the citric acid cycle.

Oxidation of Glucose

Step-wise breakdown releasing energy for ATP synthesis.

Electron Carriers

Molecules that transport electrons during cellular respiration.

Heat Loss

Energy not used for work, dissipated as heat.

Pyruvate

3-carbon product of glycolysis, enters transition step.

Cytoplasm

Location of glycolysis and initial steps of respiration.

Mitochondria

Cell organelle where aerobic respiration occurs.

Coenzyme A

Assists in transporting acetyl groups into CAC.

Oxaloacetate

4-carbon molecule that combines with acetate in CAC.

Citrate

6-carbon molecule formed in the citric acid cycle.

ATP Yield

Total ATP produced varies between aerobic and anaerobic.

Reduction

Addition of electrons, making charge more negative.

Redox Reaction

Simultaneous reduction and oxidation processes.

Phosphate Group

High energy group in ATP that donates energy.

ADP

Adenosine diphosphate, formed from ATP loss.

Phosphorylation

Addition of phosphate group to a molecule.

Exergonic Reaction

Releases energy during a chemical process.

Endergonic Reaction

Requires energy input to proceed.

Cellular Respiration

Process converting glucose to ATP, requires oxygen.

Glycolysis

First step of cellular respiration in cytoplasm.

Pyruvate

3-carbon molecule produced from glucose in glycolysis.

Citric Acid Cycle

Completes glucose oxidation, produces ATP and CO2.

NAD+

Electron carrier, accepts electrons during respiration.

FAD

Another electron carrier involved in respiration.

Acetyl CoA

Formed from pyruvate, enters citric acid cycle.

Aerobic Pathways

Require oxygen, yield more ATP per glucose.