Table of contents

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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

12. Biosignaling

Drugs & Toxins Affecting GPCR Signaling

Biochemistry

12. Biosignaling

Drugs & Toxins Affecting GPCR Signaling

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Multiple Choice

Caffeine is a(n) __________ of adenosine that blocks its receptors from activation.

Inhibitor.

Antagonist.

Agonist.

Activator.

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Understand the role of adenosine in the body: Adenosine is a neurotransmitter that typically promotes sleep and relaxation by binding to its receptors in the brain.

Identify the function of caffeine: Caffeine is known to increase alertness and reduce the feeling of tiredness.

Determine how caffeine interacts with adenosine receptors: Caffeine binds to adenosine receptors without activating them, preventing adenosine from binding and exerting its effects.

Define the term 'antagonist': In biochemistry, an antagonist is a substance that binds to a receptor and blocks or dampens the biological response, without triggering the receptor's typical action.

Conclude that caffeine acts as an antagonist: Since caffeine blocks adenosine from binding to its receptors and does not activate them, it is classified as an antagonist.