What is the function of glycerol in insect plasma?

What is the function of glycerol in insect plasma?

• A. It thickens the plasma
• B. It lowers the freezing temperature of the insect
• C. It increases respiration rate
• D. It acts as a hormone

Answer: (B)

Glycerol in insect plasma acts as a cryoprotectant that helps survival in freezing conditions. By increasing the solute concentration in the hemolymph, it lowers the freezing point of body fluids, preventing ice crystals from forming inside cells and tissues during cold stress. This antifreeze action protects cells from damage and dehydration that freezing causes. It isn’t primarily about thickening the plasma, increasing respiration rate, or signaling through a hormone, so those options don’t fit as well.

Glycerol in insect plasma acts as a cryoprotectant that helps survival in freezing conditions. By increasing the solute concentration in the hemolymph, it lowers the freezing point of body fluids, preventing ice crystals from forming inside cells and tissues during cold stress. This antifreeze action protects cells from damage and dehydration that freezing causes. It isn’t primarily about thickening the plasma, increasing respiration rate, or signaling through a hormone, so those options don’t fit as well.