Paramecium

Paramecium is a tiny, single-celled microorganism (a protozoan) usually found in pond water.

• Shape and body: It often looks like a slipper under the microscope and has a thin outer covering that helps it keep its shape.
• Movement using cilia: Its body is covered with many tiny hair-like structures called cilia. By beating these cilia together like synchronized oars, it swims smoothly through water.
• How it eats: The same cilia also help sweep food (like bacteria and tiny bits of organic matter) into a small opening, where food is taken in and digested inside the cell.
• Living in freshwater: Pond water can be “watery” (less salty) compared to the inside of the cell, so water tends to enter the paramecium. It uses a contractile vacuole (a little pumping structure) to push extra water out and stay safe.
• Why it matters: Paramecium is part of the pond food chain—by eating bacteria and being eaten by larger organisms, it helps keep the pond ecosystem balanced.

Seeing a paramecium under a microscope is a great reminder that even one cell can move, feed, and control its internal conditions like a complete living organism.