PHRM 6100 - Exam 2 Study Guide

Exam 2 Study Guide Material (PHRM 6100 - Fall 2024)

Concept Study Exercises

  1. Classification of Monosaccharides

    • a. Number of Carbons

      • Monosaccharides can be categorized based on the number of carbon atoms they contain. The common classifications include:

      • Trioses (3 Carbons)

      • Tetroses (4 Carbons)

      • Pentoses (5 Carbons)

      • Hexoses (6 Carbons)

      • Heptoses (7 Carbons)

    • b. Aldose/Ketoses

      • Aldoses contain an aldehyde group (-CHO) and ketoses contain a ketone group (C=O).

    • c. Pyranose/Furanose

      • Pyranose is a six-membered ring form of monosaccharides, while furanose is a five-membered ring form. C

    • d. Stereochemistry for Isomers

      • Monosaccharides can exist as optical isomers (enantiomers), diastereomers, and epimers.

  2. Difference between Aldose and Ketose Monosaccharides

    • An aldose is a monosaccharide that contains an aldehyde group at the end of the carbon chain, whereas a ketose contains a ketone group within the chain.

    • Example: Glucose (aldose) vs. Fructose (ketose).

  3. Physiochemical Properties of Monosaccharides and Carbohydrates

    • Generally soluble in water.

    • They exhibit a sweet taste.

    • They can form rings (cyclization).

    • They participate in redox reactions as they can be oxidized or reduced.

  4. Formation of Disaccharides and Polysaccharides

    • Disaccharides and polysaccharides are formed through glycosidic bonds, which link monosaccharides together via dehydration synthesis (removal of water).

    • Example: Sucrose is formed from glucose and fructose.

  5. Reaction Breaking Apart Bonds in Disaccharides/Polysaccharides

    • Hydrolysis reaction breaks glycosidic bonds in disaccharides and polysaccharides to release individual monosaccharides.

  6. Polysaccharides

    • Polysaccharides are large carbohydrate molecules composed of long chains of monosaccharides.

    • Homopolysaccharides consist of the same type of monosaccharide (e.g., starch), while heteropolysaccharides consist of different types (e.g., hyaluronic acid).

  7. Structure of Glycogen

    • Glycogen is a branched polymer of glucose.

    • The branching occurs due to alpha-1,6 glycosidic bonds, while linear glucose units are linked by alpha-1,4 glycosidic bonds.

    • Purpose: Serves as a major energy storage form in animal cells.

  8. Biochemical/Metabolic Pathways Involving Carbohydrates

    • a. Glycolysis

      • Anaerobic Conditions: Converts glucose to lactate; produces ATP.

      • Aerobic Conditions: Converts glucose to pyruvate; enters the citric acid cycle.

    • b. Citric Acid Cycle

      • Processes acetyl-CoA to produce NADH and FADH2 as electron carriers.

    • c. Electron Transport Chain

      • Uses NADH and FADH2 to generate ATP through oxidative phosphorylation.

    • d. Gluconeogenesis

      • The synthesis of glucose from non-carbohydrate sources, primarily during fasting.

    • e. Glycogenesis

      • The process of converting glucose to glycogen for storage.

    • f. Glycogenolysis

      • The breakdown of glycogen to release glucose for energy.

  9. Regulation of Blood Glucose

    • The body regulates blood glucose through hormonal control:

      • a. Low Blood Glucose Levels:

      • Hormones like glucagon are secreted, stimulating gluconeogenesis and glycogenolysis to increase glucose levels.

      • b. High Blood Glucose Levels:

      • Insulin is released, promoting the uptake of glucose by cells and stimulating glycogenesis.

  10. Hypoglycemia and Hyperglycemia

    • Hypoglycemia: Refers to abnormally low blood glucose levels, which can cause dizziness, shakiness, and even unconsciousness.

    • Hyperglycemia: Refers to abnormally high blood glucose levels, commonly associated with diabetes, leading to damage in various organs.

  11. Glycemic Index

    • A ranking system for carbohydrates based on their immediate effect on blood glucose levels. High glycemic index foods cause rapid spikes in blood sugar.

    • It helps in choosing foods to manage blood sugar levels effectively.

  12. Lipid Identification Based on Structure and Properties

    • a. Fatty Acids: Long hydrocarbon chains with a carboxylic acid group at one end.

    • b. Phospholipids: Composed of a glycerol backbone, two fatty acids, and a phosphate group; important for membrane structure.

    • c. Triglycerides: Formed by glycerol and three fatty acids; primary form of stored energy.

    • d. Steroids/Cholesterol: Composed of four fused carbon rings with various functional groups; hormones and structural components of membranes.

  13. Classification of Fatty Acids

    • a. Saturation: Saturated (no double bonds) vs. unsaturated (one or more double bonds).

    • b. Omega Designation: Indicates the position of the first double bond from the methyl end of the fatty acid chain (e.g., Omega-3, Omega-6).

    • c. Geometric Isomerism: Exists as cis or trans isomers based on hydrogen atom placement around double bonds.

  14. Importance of Phospholipids

    • a. Cell Membrane Composition: Form bilayer structures critical for membrane integrity and functionality.

    • b. Drug Delivery: Enhances solubility and absorption of pharmaceutical compounds through lipid bilayer compatibility.

  15. Steroid Structural Positions

    • Unique substitutions impact steroid function, e.g.,

      • Estrogens possess an aromatic A ring.

      • Androgens have a methyl group at C-19.

  16. Biochemical/Metabolic Pathways Involving Lipids

    • a. Beta Oxidation: Breakdown of fatty acids to form acetyl-CoA for energy production.

    • b. Ketogenesis: Converts excess acetyl-CoA into ketone bodies during periods of low carbohydrate intake.

    • c. Lipogenesis:

      • i. Triglyceride Synthesis: Involves converting acetyl-CoA into fatty acids and linking them with glycerol.

      • ii. Triglyceride Breakdown: Mobilization of stored triglycerides into fatty acids and glycerol.

    • d. Eicosanoid Synthesis: Involves two pathways —

      • i. Cyclooxygenase Pathway: Produces prostaglandins and thromboxanes.

      • ii. Lipooxygenase Pathway: Produces leukotrienes.

    • e. De Novo Cholesterol Synthesis: Forming cholesterol from acetyl-CoA; crucial for membrane structure and hormone synthesis.

    • f. Steroidogenesis: The production of steroids from cholesterol, critical for hormone synthesis.

  17. Reactions for Triglyceride Synthesis and Breakdown

    • a. Triglyceride Synthesis: Involves esterification of fatty acids with glycerol, requiring enzyme acyl-CoA synthetase.

    • b. Triglyceride Breakdown: Involves hydrolysis using the enzyme lipase, which releases fatty acids for energy metabolism.

  18. Importance of Lipoproteins

    • Lipoproteins facilitate the transport of lipids in the bloodstream, as lipids are hydrophobic and must be packaged for circulation.

    • Different classes (e.g., LDL, HDL) serve distinct roles in cholesterol transport and metabolism.

  19. Role of Carnitine in Fatty Acid Transport

    • Carnitine is essential for transporting long-chain fatty acids into mitochondria for beta-oxidation.

    • It forms acyl-carnitine complexes which facilitate the transport across the mitochondrial membrane.

  20. Generation of Ketone Bodies During Ketogenesis

    • Ketone bodies such as acetoacetate and beta-hydroxybutyrate are generated from excess acetyl-CoA in the liver.

    • They are released into the bloodstream, serving as alternative energy sources for peripheral tissues, especially during fasting or carbohydrate restriction.

  21. Classification of Metabolic Pathways

    • a. Glycolysis: Catabolic

    • b. Glycogenesis: Anabolic

    • c. Glycogenolysis: Catabolic

    • d. Citric Acid Cycle: Amphibolic

    • e. Electron Transport Chain: Catabolic

    • f. Beta Oxidation: Catabolic

    • g. Lipogenesis: Anabolic

    • h. Triglyceride Synthesis: Anabolic

    • i. Triglyceride Breakdown: Catabolic

    • j. Eicosanoid Synthesis: Amphibolic

    • k. Steroidogenesis: Anabolic

  22. Major Aspects of Metabolism

    • Includes catabolic (energy-releasing reactions), anabolic (energy-consuming reactions), and amphibolic pathways (both anabolic and catabolic aspects).

Problem-based Exercises

  1. Classification of Monosaccharides

    • Classify the given monosaccharides as either aldoses or ketoses.

  2. Stereochemical Designation

    • Determine the most appropriate stereochemical designation for the position of the carboxyl (COO-) group for depicted monosaccharide isomers.

  3. Classification as Furanose or Pyranose

    • Categorize the depicted monosaccharides as either furanose or pyranose.

  4. Classification of Polysaccharides

    • Identify the type of polysaccharide as either a homopolysaccharide or a heteropolysaccharide.

  5. Classification of Fatty Acids

    • Classify the provided fatty acids based on their saturation and omega designation.

  6. Classification of Lipids

    • Classify the lipids provided based on structure and properties.