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

6. Enzymes and Enzyme Kinetics

Enzyme-Substrate Complex

Biochemistry

6. Enzymes and Enzyme Kinetics

Enzyme-Substrate Complex

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Multiple Choice

Why is an enzyme in a chemical reaction often compared to a lock and key?

Because the enzyme's active site has a specific shape that fits only a particular substrate, similar to how a key fits into a specific lock.

Because enzymes permanently change their shape after binding to a substrate, like a lock breaking after use.

Because enzymes can catalyze any reaction regardless of the substrate, just as any key can open any lock.

Because enzymes and substrates are both made of the same amino acid sequence, like identical keys and locks.

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Verified step by step guidance

Understand the concept of enzyme specificity: Enzymes are biological catalysts that speed up chemical reactions. They are highly specific, meaning they only bind to particular substrates that fit their active site.

Learn about the 'lock and key' model: This analogy describes how the enzyme's active site has a unique shape that matches the shape of its substrate, similar to how a specific key fits into a specific lock.

Clarify why the enzyme's active site is crucial: The active site is the region of the enzyme where the substrate binds and the reaction occurs. Its shape and chemical properties determine which substrate can bind.

Eliminate incorrect options: For example, enzymes do not permanently change their shape after binding to a substrate, nor can they catalyze any reaction regardless of the substrate. Additionally, enzymes and substrates are not made of identical amino acid sequences.

Conclude with the correct reasoning: The enzyme's active site is specific to its substrate, which is why the 'lock and key' analogy is used to describe enzyme-substrate interactions.