Metabolism — Flashcards

Flashcard 671: Ketogenesis occurs in prolonged starvation and ketoacidosis because _____ is depleted for gluconeogenesis, causing acetyl-CoA to be shunted into ketone body synthesis.

Answer: oxaloacetate

Extra: In starvation and DKA, oxaloacetate (OAA) is consumed for gluconeogenesis. This depletion of OAA prevents the TCA cycle from utilizing acetyl-CoA (which is being produced by increased β-oxidation). Consequently, acetyl-CoA builds up and is diverted into the production of ketone bodies.

Flashcard 672: TSH increases which 2nd messenger? _____

Answer: cAMP

Flashcard 673: Free radicals may be eliminated via metal carrier proteins, such as _____ and ceruloplasmin

Answer: transferrin

Extra: Metal carrier proteins (e.g., transferrin and ceruloplasmin) sequester iron and copper, respectively, preventing them from catalyzing the formation of free radicals (e.g., via the Fenton reaction).

Flashcard 674: One role of plasmin is _____ of fibrin and fibrinogen

Answer: cleavage

Flashcard 675: In the liver, unconjugated bilirubin is converted to _____ via the enzyme UDP-glucuronyl transferase

Answer: conjugated bilirubin

Extra: UWorld:

Flashcard 676: The four glucose residues remaining on a branch after glycogen phosphorylase has shortened it are referred to as "_____"

Answer: limit dextrins

Flashcard 677: The branched glycogen molecule (pre-debranching enzyme) is cleaved by the enzyme _____ in the lysosomes, only

Answer: α-1,4-glucosidase (acid maltase)

Flashcard 678: The [A-] form of the bicarbonate buffer is _____

Answer: HCO3-

Flashcard 679: Sucrose is a disaccharide that is digested into _____ and _____ by sucrase

Answer: glucose

Flashcard 680: NAD+ is generally used as an electron carrier in _____ processes

Answer: catabolic