Feedback inhibition differs from repression because feedback inhibition
a. is less precise.
b. is slower acting.
c. stops the action of preexisting enzymes.
d. stops the synthesis of new enzymes.
e. all of the above

Verified step by step guidance

1. Understand the concept of feedback inhibition: Feedback inhibition is a regulatory mechanism where the end product of a metabolic pathway inhibits an enzyme involved in the pathway, thus preventing the overproduction of the product.
2. Understand the concept of repression: Repression is a genetic regulatory mechanism where the synthesis of enzymes is inhibited at the gene expression level, often by a repressor protein binding to the operator region of an operon.
3. Compare feedback inhibition and repression: Feedback inhibition acts on preexisting enzymes to regulate their activity, while repression affects the synthesis of new enzymes by controlling gene expression.
4. Analyze the options: Option c states that feedback inhibition stops the action of preexisting enzymes, which aligns with the definition of feedback inhibition.
5. Conclude which option best describes the difference: Based on the understanding that feedback inhibition acts on existing enzymes and repression affects enzyme synthesis, determine which option correctly highlights this distinction.

Key Concepts

Feedback Inhibition

Feedback inhibition is a regulatory mechanism in metabolic pathways where the end product of a reaction inhibits an enzyme involved in its production. This process allows cells to maintain homeostasis by preventing the overproduction of substances. It acts quickly to modulate enzyme activity, ensuring that resources are not wasted when sufficient product levels are reached.

Enzyme Regulation

Enzyme regulation encompasses various mechanisms that control enzyme activity and metabolic pathways. This includes feedback inhibition, where the end product inhibits an enzyme, and repression, which involves the reduction of enzyme synthesis. Understanding these regulatory mechanisms is crucial for comprehending how cells adapt to changes in their environment and manage energy efficiently.

Repression

Repression is a form of gene regulation where the synthesis of enzymes is decreased or halted in response to the presence of a specific metabolite. Unlike feedback inhibition, which affects existing enzymes, repression prevents the production of new enzymes, thereby controlling the overall metabolic flow. This mechanism is essential for conserving energy and resources when certain substrates are abundant.