Cellular Energetics Knowt
Enzymes and Their Function
1. Enzyme: Protein that acts as a catalyst to speed up chemical reactions.
2. Ribozyme: RNA molecule functioning as an enzyme.
3. Active Site: Region on an enzyme where the substrate binds.
4. Substrate: Reactant in an enzymatic reaction.
5. Induced Fit: The active site changes shape slightly to fit the substrate.
6. Cofactor: Non-protein ion or molecule required for enzyme function.
7. Coenzyme: Organic cofactor that assists enzymes.
8. Vitamins: Small organic molecules used to synthesize coenzymes.
Factors Affecting Enzyme Activity
9. Substrate Concentration: Higher concentration increases reaction rate until saturation.
10. Optimal pH: Specific pH where enzyme activity is highest; changes can disrupt enzyme function.
11. Temperature: Higher temperatures increase activity until denaturation.
12. Denature Loss of enzyme shape and function due to temperature or pH changes.
Enzyme Inhibition
13. Competitive Inhibition: Inhibitor competes with the substrate for the active site.
14. Noncompetitive Inhibition: Inhibitor binds elsewhere, altering enzyme shape.
Photosynthesis
15. Autotrophs: Organisms that make their own food (e.g., plants).
16. Heterotrophs: Organisms that consume others for energy.
17. Raw Materials for Photosynthesis: Carbon dioxide (CO₂) and water (H₂O).
18. Chloroplasts: Organelle where photosynthesis occurs; contains thylakoids and stroma.
19. Thylakoid: Flattened sac in the chloroplast where light reactions occur.
20. Grana: Stacks of thylakoids.
21. Stroma: Fluid-filled area in chloroplasts where the Calvin cycle occurs.
22. Chlorophyll: Pigment in thylakoid membranes that absorbs light.
Photosynthesis Processes
23. Light Reactions: Occur in the thylakoid membrane; require light to produce ATP, NADPH, and oxygen.
24. Photosystem II: Splits water to release oxygen and electrons.
25. Electron Transport Chain: Transfers electrons between Photosystem II and Photosystem I, creating an H⁺ gradient.
26. Photosystem I: Produces NADPH by reducing NADP⁺.
27. ATP Synthase: Uses H⁺ gradient to synthesize ATP.
28. Chemiosmosis: Process of ATP production tied to an H⁺ gradient.
29. Calvin Cycle: Light-independent reactions in the stroma that use ATP and NADPH to convert CO₂ into sugars.
Cellular Respiration
30. Aerobic Respiration: Requires oxygen; occurs in mitochondria.
31. Anaerobic Respiration: Does not require oxygen; occurs in the cytoplasm.
Steps of Cellular Respiration
32. Glycolysis: Occurs in the cytoplasm; breaks down glucose into pyruvate, producing ATP and NADH.
33. Prep Reaction: Converts pyruvate into acetyl CoA, releasing CO₂ and forming NADH.
34. Citric Acid Cycle: Occurs in the mitochondrial matrix; produces CO₂, ATP, NADH, and FADH₂.
35. Electron Transport Chain (ETC): Occurs in mitochondrial cristae; uses NADH and FADH₂ to produce ATP.
Key Molecules
36. ATP: Main energy currency of the cell.
37. NADH/FADH₂: Electron carriers in cellular respiration.
38. Chemiosmosis: Uses H⁺ gradient in mitochondria to produce ATP.
Reactants and Products
39. Glycolysis Reactants: Glucose, 2 NAD⁺, 2 ATP, 4 ADP+P.
40. Glycolysis Products: 2 Pyruvate, 2 NADH, 4 ATP (net gain of 2).
41. Citric Acid Cycle Reactants: 2 Acetyl CoA, 6 NAD⁺, 2 FAD, 2 ADP+P.
42. Citric Acid Cycle Products: 4 CO₂, 6 NADH, 2 FADH₂, 2 ATP.
43. ETC Reactants: 10 NADH, 2 FADH₂, 6 O₂.
44. ETC Products: 34-36 ATP, 6 H₂O.
Broad Concepts
45. Metabolic Pathway: Ordered sequence of linked reactions.
46. Activation Energy: Energy needed to start a reaction.
47. Coupled Reactions: Energy-releasing reactions drive energy-requiring reactions.