Enzyme Inhibition and Metabolic Pathways

The video covers IB section 8.1, focusing on metabolic pathways and their regulation. It explains how enzymes lower activation energy to facilitate reactions and discusses competitive, non-competitive, and end product inhibition. The video also introduces the induced fit model, illustrating enzyme-substrate interactions.

What is a metabolic pathway?

• A single-step chemical reaction

• A random series of reactions

• A sequence of linked chemical reactions

• An unrelated set of reactions

Which of the following is an example of a metabolic pathway?

• Photosynthesis

• Evaporation

• Melting ice

• Boiling water

How do enzymes affect chemical reactions in metabolic pathways?

• They have no effect on activation energy

• They stop the reaction

• They decrease the activation energy

• They increase the activation energy

In competitive inhibition, what competes with the substrate?

• An inhibitor molecule

• A different substrate

• A water molecule

• Another enzyme

Where does a non-competitive inhibitor bind on an enzyme?

• Active site

• Substrate site

• Alisic site

• Product site

What happens to the enzyme's active site in non-competitive inhibition?

• It disappears

• It changes shape

• It becomes more active

• It remains unchanged

What is the role of the end product in end-product inhibition?

• It acts as a non-competitive inhibitor

• It has no effect

• It acts as a competitive inhibitor

• It accelerates the reaction

In the conversion of theine to isoline, what acts as the inhibitor?

• ATP

• Isoline

• Theine

• Phosphofructokinase

What does the induced fit model suggest about enzyme-substrate interaction?

• Enzymes are rigid and unchanging

• Enzymes can slightly change shape to fit substrates

• Substrates change shape to fit enzymes

• Enzymes and substrates do not interact

Why is the induced fit model important for enzyme specificity?

• It allows any substrate to bind

• It ensures only specific substrates can bind

• It prevents any substrate from binding

• It allows enzymes to bind to multiple substrates