Metabolism — Flashcards

Flashcard 1411: Does glutamine cause a change in blood pH? _____

Answer: No

Flashcard 1412: A _____ enzyme joins two molecules together using a source of energy (e.g., ATP)

Answer: Synthetase (Ligase)

Extra: **Synthetase**: Requires energy (usually from ATP hydrolysis) to join two molecules together. Categorized as **Ligases**. **Synthase**: Catalyzes a synthesis process without requiring energy from nucleoside triphosphates (ATP/GTP). Often categorized as **Lyases** or **Transferases**.

Flashcard 1413: Synthesis of GABA from glutamate requires _____ as a cofactor

Answer: vitamin B6

Flashcard 1414: _____ is a measure of the percent of transferrin molecules that are bound by iron

Answer: % saturation

Flashcard 1415: Which second messenger is released upon binding of cholecystokinin to CCKA receptors?_____

Answer: IP3/Ca2+

Flashcard 1416: Glycogen phosphorylase is allosterically activated by _____ (muscle)

Answer: AMP

Flashcard 1417: The **Amyloid Precursor Protein (APP)** on neurons is broken down by **\_\_\_\_\_ cleavage**, resulting in the formation of **A$\beta$ amyloid** particles.

Answer: $\beta$ (beta) cleavage

Extra: APP is normally cleaved by $\alpha$-secretase (non-amyloidogenic). Cleavage by $\beta$-secretase followed by $\gamma$-secretase results in the production of A$\beta$ (amyloid beta) peptides, which aggregate to form the plaques seen in Alzheimer's disease.

Flashcard 1418: Which neurotransmitter(s) are broken down by monoamine oxidase A (MAO-A)? _____

Answer: Serotonin, norepinephrine, and dopamine

Flashcard 1419: Activated vitamin K acts as a co-factor for the enzyme _____

Answer: Gamma-glutamyl carboxylase (γ-glutamyl carboxylase)

Flashcard 1420: Muscle cannot participate in gluconeogenesis because it lacks the enzyme _____

Answer: glucose-6-phosphatase