VGO-0164
QUESTION
Which of the following cryoprotective are used in semen freezing:
(a) Glycerol
(b) Acetic acid
(c) Normal saline
(d) DMSO
OPTIONS
(A) Only b and c
(B) Only a and c
(C) Only a and d
(D) Only b and c
ANSWER
(C) Only a and d
EXPLANATION
Glycerol and dimethyl sulfoxide are permeating cryoprotectants that reduce cellular injury during freezing and thawing. Acetic acid is not a standard sperm cryoprotectant, and normal saline alone cannot provide adequate protection against ice formation and freeze-concentration effects. Consequently, only the combination containing glycerol and DMSO correctly identifies two cryoprotective agents among the listed substances.
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Veterinary Gynaecology and Obstetrics · 240 Questions
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