Table of contents

1. Introduction to Biochemistry4h 34m
2. Water3h 23m
3. Amino Acids8h 10m
4. Protein Structure10h 4m
5. Protein Techniques14h 5m
6. Enzymes and Enzyme Kinetics13h 38m
7. Enzyme Inhibition and Regulation 8h 42m
8. Protein Function 9h 41m
9. Carbohydrates7h 49m
10. Lipids5h 49m
11. Biological Membranes and Transport 6h 37m
12. Biosignaling9h 45m
Review 1: Nucleic Acids, Lipids, & Membranes2h 47m
Review 2: Biosignaling, Glycolysis, Gluconeogenesis, & PP-Pathway3h 12m
Review 3: Pyruvate & Fatty Acid Oxidation, Citric Acid Cycle, & Glycogen Metabolism2h 26m
Review 4: Amino Acid Oxidation, Oxidative Phosphorylation, & Photophosphorylation1h 48m

1. Introduction to Biochemistry

Carbohydrates

Biochemistry

1. Introduction to Biochemistry

Carbohydrates

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Multiple Choice

Which macromolecule provides the highest amount of energy per gram when metabolized in the human body?

Lipids

Carbohydrates

Nucleic acids

Proteins

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Verified step by step guidance

Understand the concept of energy yield: When macromolecules are metabolized, they release energy that is measured in kilocalories per gram (kcal/g). Different macromolecules provide varying amounts of energy due to their chemical structure and the number of bonds available for oxidation.

Review the energy yield of each macromolecule: Lipids provide approximately 9 kcal/g, carbohydrates and proteins each provide about 4 kcal/g, and nucleic acids are not typically metabolized for energy in significant amounts in the human body.

Analyze why lipids provide the highest energy: Lipids have long hydrocarbon chains with many C-H bonds, which release a large amount of energy during oxidation. This makes them the most energy-dense macromolecule.

Consider the metabolic pathways: Lipids undergo beta-oxidation, which generates acetyl-CoA for entry into the citric acid cycle, producing a high yield of ATP. Carbohydrates are metabolized via glycolysis and the citric acid cycle, while proteins are broken down into amino acids and metabolized depending on their structure.

Conclude based on the comparison: Lipids provide the highest energy per gram due to their chemical composition and metabolic pathways, making them the most efficient energy source among the listed macromolecules.