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

2. Water

Acids and Bases

Biochemistry

2. Water

Acids and Bases

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Multiple Choice

1. Which of the following primarily stimulates the secretion of hydrochloric acid (HCl) in the stomach?

Cholecystokinin (CCK)

Secretin

Gastrin

Pepsinogen

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Verified step by step guidance

Understand the role of hydrochloric acid (HCl) in the stomach: HCl is secreted by parietal cells in the gastric lining and plays a critical role in digestion by denaturing proteins and activating pepsinogen into pepsin.

Review the function of gastrin: Gastrin is a hormone secreted by G cells in the stomach lining. It primarily stimulates parietal cells to secrete HCl and promotes gastric motility.

Compare the roles of other options: Cholecystokinin (CCK) primarily stimulates the release of digestive enzymes from the pancreas and bile from the gallbladder, while secretin regulates the secretion of bicarbonate from the pancreas to neutralize stomach acid. Pepsinogen is an inactive precursor to pepsin and is activated by HCl, but it does not stimulate HCl secretion.

Identify the correct answer: Gastrin is the primary hormone responsible for stimulating HCl secretion in the stomach, as it directly acts on parietal cells.

Conclude the reasoning: Based on the physiological roles of the options provided, gastrin is the correct answer because it directly stimulates the secretion of hydrochloric acid in the stomach.