Energy CRAM PDF

Energy CRAM General Overview ATP Creation Begins with ADP (Adenosine Diphosphate), which has 2 phosphates. Adding another phosphate through phosphorylation creates ATP (Adenosine Triphosphate). This process is endergonic, meaning it requires energy input....

Energy CRAM General Overview ATP Creation Begins with ADP (Adenosine Diphosphate), which has 2 phosphates. Adding another phosphate through phosphorylation creates ATP (Adenosine Triphosphate). This process is endergonic, meaning it requires energy input. ATP Synthase: the enzyme responsible for synthesizing ATP. Quick Energy Storage ATP is a reactive molecule that releases energy quickly, making it suitable for immediate use. Combines negatively charged phosphates that repel each other, creating potential energy. Cellular Use of ATP ATP is the primary energy carrier in cells, crucial for various processes including: Cell Cycle: ATP is essential for cell division and overall cellular metabolism. Building Polymers: ATP helps assemble monomers into polymers. Movement: Required for muscle contractions. Active Transport: ATP powers the movement of substances against their concentration gradients. Cell Communication: ATP plays a role in signaling pathways. Photosynthesis Active vs. Passive Transport Passive Transport: Simple Diffusion: Molecules move from high to low concentration without energy input. Facilitated Diffusion: Larger or hydrophilic molecules require assistance from transport proteins but still move high to low concentration without energy. Active Transport: Requires energy to move molecules from low to high concentration, often through a transport protein. Light Wavelength Absorption Chlorophyll: Primarily absorbs violet, blue, orange, and red wavelengths.  Green Light: Around 550 nm, is reflected and thus not utilized, making plants appear green. Location of Photosynthesis Occurs within chloroplasts: Thylakoids: Contain light-absorbing pigments, where light- dependent reactions occur. Stroma: Aqueous space where the Calvin cycle (light-independent phase) takes place, synthesizing sugars. Stages of Photosynthesis Light-Dependent Reactions: Require sunlight, producing ATP and NADPH in thylakoids. Calvin Cycle: Does not require light, utilizes ATP and NADPH to convert carbon dioxide into glucose in the stroma. Photosynthesis Reaction Reaction: 6 CO2 + 6 H2O + light energy → C6H12O6 + 6 O2 in chloroplasts. Role of Oxygen in Photosynthesis Oxygen is released during the splitting of water molecules to replace energized electrons in chlorophyll, exiting through stomata. Electron Transport Chain Initially, energized electrons from chlorophyll navigate through an electron transport chain, pumping hydrogen ions and creating a concentration gradient. Electrons ultimately help produce NADPH and ATP used in the Calvin cycle. Cellular Respiration Entry Points for Organic Molecules Entirely dependent on glycolysis for carbohydrates, which yield pyruvate ready for further processing in the mitochondria. Amino acids and fatty acids provide alternative pathways for energy production. Stages of Aerobic Respiration Sequence: Glycolysis → Krebs Cycle → Electron Transport Chain. Glycolysis occurs in the cytoplasm, while the Krebs cycle and oxidative phosphorylation take place in the mitochondria. Production of ATP Glycolysis: 2 ATP, 2 NADH, 2 pyruvate. Krebs Cycle: 2 ATP, 8 NADH, and 2 FADH2. Electron Transport Chain: Up to 34 ATP can be produced. Electron Transport Chain Mechanism Energized electrons from NADH and FADH2 pass through proteins, establishing ATP while oxygen acts as the final electron acceptor to form water. Energy Release Energy not stored in ATP during cellular metabolism is released as heat, aiding in thermoregulation for endothermic organisms. Comparison: Aerobic vs. Anaerobic Respiration Aerobic Respiration: High ATP yield (~38 ATP), utilizes oxygen, and occurs in both eukaryotes and prokaryotes. Anaerobic Respiration: Low yield (2 ATP), occurs without oxygen, primarily in anaerobic bacteria and some eukaryotes (like yeast). Fermentation Types Alcoholic Fermentation: Produces alcohol and carbon dioxide. Lactic Acid Fermentation: Produces lactic acid; occurs in human muscle cells during high demand for energy when oxygen is temporarily insufficient.