Why Is the Hydrolysis of GTP by a G-Protein Essentially

question 17

Multiple Choice

Why is the hydrolysis of GTP by a G-protein essentially irreversible?

• A) GDP immediately hydrolyzes to GMP and Pi
• B) GDP is metabolized to cGMP
• C) GDP remains bound after Pi is liberated
• D) GTP cannot be synthesized from GDP
• E) The Km for Pi is too low

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Definitions:

ATP

Adenosine triphosphate, a molecule that carries energy within cells, facilitating various cellular functions.

Enzymes

Biological molecules that act as catalysts to speed up chemical reactions in the body, essential for numerous metabolic processes.

Biogeographer

A scientist who studies the distribution of species and ecosystems in geographic space and through geological time.

Continental Drift

The theory that continents move across the Earth's surface over geologic time, leading to the formation and separation of land masses.