Which small, bottle-shaped structure is used by Paramecium for defense?

Which small, bottle-shaped structure is used by Paramecium for defense?

• A. Trichocyst
• B. Contractile vacuole
• C. Cilia
• D. Mitochondrion

Answer: (A)

Paramecium relies on specialized extrusive organelles called trichocysts for defense. These are small, bottle-shaped capsules in the cell cortex that rapidly eject a long thread when stimulated. The expelled thread can deter or entangle predators, providing a quick protective response. Other structures serve different roles: contractile vacuoles regulate water balance, cilia are for movement and feeding, and mitochondria generate energy. So the bottle-shaped structure used for defense is the trichocyst.

Paramecium relies on specialized extrusive organelles called trichocysts for defense. These are small, bottle-shaped capsules in the cell cortex that rapidly eject a long thread when stimulated. The expelled thread can deter or entangle predators, providing a quick protective response. Other structures serve different roles: contractile vacuoles regulate water balance, cilia are for movement and feeding, and mitochondria generate energy. So the bottle-shaped structure used for defense is the trichocyst.