Unicellular Organisms

Unicellular organism

An organism made up of only one cell.

Organelles

Small structures inside a cell that perform specific functions.

Cytoplasm

The jelly-like fluid inside a cell where organelles are found.

Cell membrane

The outer layer of a cell that controls what enters and leaves.

Nucleus

The part of a cell that contains DNA.

Paramecium

A slipper-shaped unicellular organism found in pond water.

Cilia

Tiny hair-like structures that help paramecium move.

Vacuole

A storage bubble in cells, often used to digest food or pump out water.

Contractile vacuole

A special vacuole that removes extra water from the cell.

Oral groove

The mouth-like opening where food enters a paramecium.

Pellicle

A thin, flexible outer covering of a paramecium.

Micronucleus / Macronucleus

Two types of nuclei in a paramecium; they control different functions like reproduction and everyday activities.

Amoeba

A shapeless unicellular organism found in warm freshwater.

Pseudopod

A “false foot” used by amoebas to move and eat.

Ectoplasm / Endoplasm

The outer (ecto) and inner (endo) parts of the amoeba’s cytoplasm.

Protozoan

A type of unicellular organism, including paramecia and amoebas.