When Protein Molecules Are Used as Energy Sources, the Amino

question 54

Multiple Choice

When protein molecules are used as energy sources, the amino groups of the amino acids are ____ and the carbon backbones enter ____.

• A)excreted as free amino groups (-NH₂); glycolysis
• B)build new proteins; the electron transfer chain
• C)excreted as ammonia (NH₃); the citric acid cycle
• D)used to synthesize nucleic acids; glycolysis
• E)converted to glycogen; citric acid cycle

---

Definitions:

Offspring

The biological children or progeny of an organism, resulting from reproduction.

Genetic Fitness

The reproductive success of an individual with a particular genotype, measured by the individual's ability to pass on their genes to the next generation.

Evolution

The mechanism by which distinct species of life are considered to have emerged and branched out from earlier versions throughout Earth's history.

Proximate Causes

Direct, immediate reasons behind an occurrence or behavior, distinguishing from deeper, underlying reasons.