VGO-0055
QUESTION
Prolonged half-life of eCG is due to presence of?
OPTIONS
(A) Acetic acid
(B) Propionic acid
(C) Sialic acid
(D) Hydrochloric acid
ANSWER
(C) Sialic acid
EXPLANATION
The extensive carbohydrate content of equine chorionic gonadotropin, particularly terminal sialic acid residues, slows its clearance and contributes to its prolonged circulating half-life. Acetic and propionic acids are short-chain fatty acids rather than the relevant glycoprotein residues. Hydrochloric acid is unrelated to this molecular feature. Sialylation explains why eCG has a more sustained action than shorter-lived gonadotropins.
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Veterinary Gynaecology and Obstetrics · 240 Questions
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