Biochemistry: Catabolism and Anabolism

Catabolism: The breakdown of complex molecules into simpler ones, releasing energy.
Anabolism: The synthesis of complex molecules from simpler ones, requiring energy.
Exergonic Reaction: Releases energy, often as heat, and has a negative change in free energy (ΔG).
Endergonic Reaction: Requires energy to proceed, has a positive change in free energy (ΔG).

Reducing Equivalents: Electron carriers like NADH and FADH2 carry electrons and release energy when transferring them to other molecules.
ATP Hydrolysis: Breaking the phosphate bonds in ATP releases energy, which can be used to power endergonic reactions (coupled reaction).

Enzyme: A biological catalyst that speeds up chemical reactions without being consumed.
Enzyme Substrate: The specific molecule that an enzyme acts upon.
Active Site: The region on the enzyme where the substrate binds.
Activation Energy: The minimum energy required for a reaction to occur. Enzymes lower the activation energy, making reactions happen faster.

Apoenzyme: The protein component of an enzyme.
Cofactor: A non-protein molecule required for enzyme activity, can be metal ions or organic coenzymes.

Enzyme Inhibitors: Molecules that block enzymatic function, preventing the enzyme from binding to its substrate.
Competitive Inhibition: The inhibitor binds to the active site, preventing the substrate from binding.
Non-competitive Inhibition: The inhibitor binds to a different site on the enzyme, changing its shape and preventing substrate binding.
Antimicrobial Treatments: Block the activity of essential enzymes in pathogens, inhibiting their growth and survival.

Temperature: Extreme temperatures can denature the enzyme, altering its shape and preventing function. Optimal temperature for each enzyme varies.
pH: Enzymes have optimal pH ranges. Changes outside this can affect their activity and lead to denaturation.

Cellular Respiration: The process of converting glucose into ATP, the cell's energy currency.
Glycolysis: Breakdown of glucose into pyruvate, occurs in the cytoplasm, generates ATP and reducing equivalents.
Krebs Cycle (Citric Acid Cycle): Further breakdown of pyruvate, generates ATP and reducing equivalents, occurs in the mitochondria.
Electron Transport Chain: Utilizes reducing equivalents from glycolysis and the Krebs Cycle to generate ATP through oxidative phosphorylation, occurs in the mitochondrial membrane.
Substrate-Level Phosphorylation: ATP is produced directly from a metabolic reaction, occurs in glycolysis and the Krebs Cycle, less efficient than oxidative phosphorylation.

Oxidative Phosphorylation: Uses the energy from the electron transport chain to generate ATP, the primary method of ATP production.
Net ATP Production: Cellular respiration produces approximately 38 ATP molecules per glucose molecule. Glycolysis alone produces much less.

Fermentation: Generates ATP through glycolysis, but lacks a final electron acceptor for the electron transport chain, leading to the production of byproducts like lactic acid or ethanol.
Final Electron Acceptor: Oxygen is the usual final electron acceptor in cellular respiration, but some organisms can use other molecules like nitrates or sulfates.
Industrial & Food Production: Fermentation is used in the production of various food products like yogurt, cheese, bread, wine, and beer.

Prokaryotic Binary Fission: A single-celled organism divides into two identical cells.
Eukaryotic Mitosis: Nuclear division in eukaryotic cells, followed by cytokinesis (cell division).

Logarithmic (Exponential) Growth: Under ideal conditions, microbial populations increase rapidly and exponentially.

Lag Phase: Initial period with slow or no growth, microorganisms adjust to the new environment.
Log Phase: Rapid growth, with a steady increase in microbial population.
Stationary Phase: Growth rate plateaus, the number of new cells equals the number of dying cells due to limited resources.
Death Phase: Nutrient depletion and waste accumulation lead to a decline in the microbial population.

Biofilm Formation: Microorganisms adhere to a surface, forming a structured community encased in a matrix of extracellular polymers.
Clinical Environments: Biofilms in hospitals and medical devices can cause infections, making treatment challenging due to their resistance to antibiotics.

Obligate Aerobes: Require oxygen for growth, have enzymes to detoxify reactive oxygen species (ROS).
Obligate Anaerobes: Cannot grow in the presence of oxygen, lack enzymes to detoxify ROS, oxygen is toxic.
Facultative Anaerobes: Can grow with or without oxygen, prefer oxygen for efficient energy production.
Aerotolerant Anaerobes: Can tolerate oxygen but don't use it for growth, have mechanisms to detoxify ROS
Microaerophiles: Require low oxygen levels, grow in the upper layers of liquid thioglycolate broth.
ROS: Reactive oxygen species are toxic byproducts of oxygen metabolism, damage cells.
Enzymes: Catalase and superoxide dismutase are enzymes used to detoxify ROS.

Optimal Growth Temperature: The temperature at which an organism grows most rapidly.
Below Optimal Temperature: Growth slows down, enzymes work less efficiently.
Above Optimal Temperature: Enzymes denature, leading to cell death.