Ch.5 Microbial metabolism Flashcards
What is metabolism?
The sum of all chemical reactions in a cell or organism
What is catabolism?
The breakdown of larger molecules to release energy.
What is anabolism?
synthesis The process of building larger molecules from smaller ones, requiring energy.
Why are redox reactions important in metabolism?
They transfer electrons, enabling energy production in processes like cellular respiration.
What is substrate-level phosphorylation?
ATP is produced directly from a substrate molecule during glycolysis and the Krebs cycle.
What is oxidative phosphorylation?
ATP is produced via electron transfer in the electron transport chain using a proton gradient.
What is photophosphorylation?
ATP is produced using light energy in photosynthesis.
What is a holoenzyme?
A complete enzyme, consisting of an apoenzyme (protein) and a cofactor (non-protein component).
What factors can affect enzyme activity?
Temperature, pH, substrate concentration, inhibitors, and cofactors.
What are the three stages of aerobic glucose catabolism?
Glycolysis, Krebs cycle, and electron transport chain (oxidative phosphorylation).
How does anaerobic respiration differ from aerobic respiration?
Anaerobic respiration uses a non-oxygen electron acceptor, producing less ATP than aerobic respiration.
What is chemiosmosis?
The process by which a proton gradient drives ATP synthesis in oxidative phosphorylation.
Why do alternate pathways for carbohydrate catabolism exist?
To generate ATP under anaerobic conditions or when oxygen is scarce.
What is fermentation?
An anaerobic process that produces ATP without oxygen, generating byproducts like lactic acid or ethanol.
How does photosynthesis convert light energy?
It uses light, carbon dioxide, and water to produce glucose and oxygen.
What is the difference between cyclic and noncyclic photophosphorylation?
Cyclic uses only Photosystem I and produces ATP, while noncyclic uses both Photosystems I and II, producing ATP and NADPH.
What is the purpose of the Calvin Cycle?
To convert carbon dioxide into glucose using ATP and NADPH.
How are catabolic intermediates important for anabolism?
They provide building blocks for processes like amino acid and fatty acid synthesis.
Why is metabolism tightly regulated?
To maintain energy balance and ensure proper functioning of cellular processes.
What is the difference between cyclic and noncyclic photophosphorylation?
Cyclic uses only photosystem 1 and produces ATP, while noncyclic uses both photosystems I and II, producing ATP and NADPH
How are catabolic intermediates important for anabolism?
They provide building blocks for processes like amino acid and fatty acid synthesis.
Why is metabolism tightly regulated?
To maintain energy balance and ensure proper functioning of cellular processes.
