The Image Below Diagrams the Action of an Enzyme

question 55

Multiple Choice

The image below diagrams the action of an enzyme.Notice that the enzyme is depicted as being more tightly wrapped around the substrates in step 2 than it is in step 1.Why is this?

• A) When a substrate locks into the active site of an enzyme,the enzyme changes shape to mold itself around the substrates.
• B) Generally,the size of a substrate is larger than the size of the active site into which it must fit.When the substrate enters the active site,the active site must stretch to fit.
• C) Before catalysis can occur,a substrate must change its shape so that it fits into the active site of the enzyme more precisely.
• D) Most active sites are only designed to hold one substrate.In this image,two substrates enter the active site,creating a tighter fit.

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Definitions:

Secondary Appraisal

The process of evaluating one's potential to cope with or respond to a threatened or challenging event after its significance has been assessed.

General Adaptation Syndrome

A three-stage response (alarm, resistance, exhaustion) to stress theorized by Hans Selye, illustrating how stress affects the body over time.

Hans Selye

A pioneering Hungarian-Canadian endocrinologist known for his research on the stress response.

Exhaustion Stage

The final stage of the stress response, where the body can no longer resist the stressors and may lead to burnout or health problems.