Chapter 3 Outline - Biology PDF

Let’s fill out the outline with explanations for each point: Chapter 3 Outline 1. Describe the structure and function of ATP as well as how ATP can be stored and released. Structure of ATP: Adenosine triphosphate (ATP) consists of: An adenine base...

Let’s fill out the outline with explanations for each point: Chapter 3 Outline 1. Describe the structure and function of ATP as well as how ATP can be stored and released. Structure of ATP: Adenosine triphosphate (ATP) consists of: An adenine base A ribose sugar Three phosphate groups connected by high-energy bonds. Function of ATP: ATP is the primary energy currency in cells, providing energy for various cellular processes like muscle contraction, transport, and chemical reactions. Energy storage and release: ATP stores energy in the bonds between its phosphate groups. Energy is released when ATP is hydrolyzed to ADP (adenosine diphosphate) and an inorganic phosphate (Pi). 2. Compare and contrast potential and kinetic energy and describe how they relate to the Laws of Thermodynamics. Potential energy: Stored energy due to position or structure (e.g., energy in chemical bonds). Kinetic energy: Energy of motion (e.g., moving particles, heat). Relation to the Laws of Thermodynamics: First law: Energy cannot be created or destroyed, only transformed (e.g., chemical potential energy in glucose is converted to ATP and heat). Second law: Energy transformations are inefficient, and some energy is always lost as heat, increasing entropy (disorder). 3. Explain the three major types of chemical reactions: synthesis, decomposition, and exchange (oxidation-reduction). Synthesis reactions: Two or more reactants combine to form a larger molecule (e.g., ).  Decomposition reactions: A large molecule is broken into smaller molecules or atoms (e.g., ). Exchange reactions: Bonds are broken and reformed as reactants are rearranged (e.g., ). Oxidation-reduction (redox): A specific type of exchange reaction where electrons are transferred, involving oxidation (loss of electrons) and reduction (gain of electrons). 4. Describe how reactions are classified using the following terms: anabolic, catabolic, endergonic, exergonic, reversible, irreversible. Anabolic: Reactions that build complex molecules from simpler ones (require energy, e.g., protein synthesis). Catabolic: Reactions that break down complex molecules into simpler ones (release energy, e.g., glycolysis). Endergonic: Require energy input (e.g., ATP synthesis). Exergonic: Release energy (e.g., ATP hydrolysis). Reversible: Can proceed in both forward and reverse directions depending on conditions (e.g., carbonic acid formation). Irreversible: Proceed in one direction only (e.g., combustion of glucose). 5. Define reaction rate, activation energy, catalyzed reaction, and uncatalyzed reaction. Reaction rate: The speed at which reactants are converted to products. Activation energy: The minimum energy required to start a reaction. Catalyzed reaction: A reaction accelerated by a catalyst, such as an enzyme. Uncatalyzed reaction: A reaction that occurs without a catalyst and generally has a slower rate. 6. Explain the structure and function of enzymes and why they are important to the human body. Structure of enzymes: Proteins with a specific 3D shape that includes an active site where substrates bind. Function of enzymes: Lower activation energy, speeding up biochemical reactions.  Importance: Enable essential biochemical processes (e.g., digestion, DNA replication) to occur at rates compatible with life. 7. Describe the mechanism of enzyme action and discuss the role of the active site and cofactors in that process. Mechanism: 1. Substrate binds to the enzyme’s active site. 2. Enzyme-substrate complex forms, lowering activation energy. 3. Products are released, and the enzyme is unchanged. Active site: The region on the enzyme where the substrate binds. Cofactors: Non-protein molecules (e.g., metal ions, vitamins) that assist enzymes in catalysis. 8. Describe the effects of substrate concentration, temperature, and pH on reaction rates. Substrate concentration: Increasing concentration increases reaction rate until enzymes are saturated. Temperature: Optimal temperature maximizes enzyme activity (too high causes denaturation). pH: Each enzyme has an optimal pH range (e.g., pepsin in the stomach works best at pH ~2). 9. Compare and contrast competitive and noncompetitive inhibition. Competitive inhibition: Inhibitor binds to the active site, blocking substrate binding. Noncompetitive inhibition: Inhibitor binds to a site other than the active site (allosteric site), changing the enzyme’s shape and reducing activity. 10. Define metabolism and explain how metabolic pathways are examples of negative feedback. Metabolism: The sum of all chemical reactions in a cell or organism. Negative feedback in metabolic pathways: Final products inhibit earlier steps to regulate pathway activity. Example: High ATP levels