Enzymes L2

Enzymes L2

Fill in the Blank

In the lock-and-key model of enzyme action:

- the active site has a rigid shape

- only substrates with the matching shape can fit

- the substrate is a ??? that fits the lock of the active site

Multiple Select

Enzymes may recognize and catalyze the following...

• phagocytosis

• single substrates

• one or two reactant types

• a group of similar substrates

• a particular bond or linkage

Multiple Choice

An enzyme speeds up a reaction by

• lowering the activation energy.
• raising the activation energy.
• releasing energy.
• absorbing energy.

Multiple Choice

What is the name for a mechanism of enzyme activity?

• Lock and key

• jigsaw puzzle

• hammer and nail

• two hands pattern

Multiple Select

What are key features of the lock-and-key model?

• the active site has a rigid shape.

• only substrates with the matching shape can fit.

• the substrate is a key that fits the lock of the active site

• the ES complex formed is rigid

Multiple Select

What are key features of the induced fit model?

• only substrates with the matching shape can fit

• the active site is flexible, not rigid

• the shapes of the enzyme, active site, and substrate adjust to maximize the fit

• greater range of substrate specificity

Open Ended

Contrast the Lock-and-Key model of enzyme action with the Induced Fit model.

Multiple Choice

Which summarises step one?

• EP --> E + P

• ES --> EP

• E + S --> ES

Multiple Choice

What summarises step 2?

• E + S --> ES

• EP --> E + P

• ES --> EP

Multiple Choice

Which summarises step 3?

• E + S --> ES

• EP --> E + P

• ES --> EP

Multiple Choice

Each enzyme only has 1 substrate that will fit its active site.  What is this called?

• reusablility
• denaturation
• specificity
• fragility

Multiple Choice

An enzyme speeds up a reaction by

• lowering the activation energy.
• raising the activation energy.
• releasing energy.
• absorbing energy.

Multiple Choice

In the diagram, what is letter A? 

• product
• substrate
• enzyme-substrate complex
• active site

Multiple Choice

What is structure A?

• Substrate
• Active site
• Enzyme
• Products

Multiple Choice

Which of the following tasks listed below is most associated with enzymes?

• catalyze chemical reactions                  
• store genetic information       
• store chemical energy in the cell   
• dissolve nutrients and minerals 

Multiple Choice

Where do substrates bind on an enzyme?

• voltage-gated channels
• surface receptor
• calcium channels
• active site

Poll

Rate your confidence with the enzymes topic so far...

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• 2

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• 4

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