Biological Energy and Enzymes

These flashcards cover key concepts regarding biological energy, enzymes, reaction types, and metabolic processes.

What does a negative ΔG indicate about a reaction?

It indicates that the reaction is exergonic and spontaneous.

What is the difference between endergonic and exergonic reactions?

Endergonic reactions require energy input (ΔG is positive), while exergonic reactions occur spontaneously and release energy (ΔG is negative).

What effect do enzymes have on activation energy?

Enzymes lower the activation energy required for a reaction.

What is the lock and key model in enzyme activity?

It describes how an enzyme's active site is specifically shaped to fit a particular substrate.

What happens to an enzyme if there is a significant change in temperature or pH?

The enzyme can denature, losing its functionality.

What are coupled reactions?

They involve pairing an endergonic reaction with an exergonic reaction to make the overall process spontaneous.

What role do temperature and concentration play in reaction rates?

An increase in temperature raises molecular motion and collisions; an increase in concentration increases the number of collisions, both speeding up reactions.

What happens during competitive inhibition?

It prevents the substrate from binding to the active site of the enzyme.

What is the primary difference between anabolism and catabolism?

Anabolism is the building up of molecules and requires energy, while catabolism is the breakdown of molecules and releases energy.

What is feedback inhibition in metabolic pathways?

It is a regulatory mechanism where the product of a pathway inhibits an enzyme involved earlier in the pathway.

Which compound is oxidized and which is reduced: Na + Cl → Na + Cl?

Na is oxidized and Cl is reduced.

What is an allosteric site?

An area on an enzyme separate from the active site where a molecule can bind to regulate enzyme activity.