Back to: ZOOLOGY 100 Level
It’s always exciting to have you here—eager, focused, and full of potential! Today’s lesson brings us face to face with some of the smallest but most fascinating living things you’ll ever learn about. You may not see them with your naked eyes, but they’re very much alive and doing big things in their tiny world. Let’s meet Amoeba, Paramecium, and Planaria—tiny champions of life!
Examples: Amoeba, Paramecium, Planaria
Amoeba: The Shape-Shifting Survivor
Amoeba is a single-celled organism found mostly in freshwater like ponds, slow-moving streams, or even damp soil. You’ll need a microscope to see it because it’s very tiny.
- Movement: Amoeba moves using parts of its body called pseudopodia (false feet). It stretches a part of itself forward and the rest of the body flows into it.
- Feeding: It surrounds its food—usually smaller organisms or particles—with its pseudopodia and “swallows” it in a process called phagocytosis.
- Reproduction: It reproduces by binary fission—splitting itself into two new Amoebas.
- Special Feature: Amoeba can change its shape at any time, which helps it survive tough conditions.
Paramecium: The Tiny Swimmer
Paramecium is also a single-celled organism, shaped like a slipper. It lives in water and is famous for how fast and gracefully it moves.
- Movement: It moves using tiny hair-like structures called cilia. These beat quickly to help it swim and turn.
- Feeding: The cilia also help push food into the paramecium’s mouth opening. It eats small bacteria and particles in water.
- Reproduction: Paramecium usually reproduces asexually through binary fission, but sometimes it exchanges genetic material through conjugation.
- Special Feature: It has two nuclei—a large one for everyday functions and a small one for reproduction.
Planaria: The Regeneration Expert
Planaria is a flatworm often found in fresh water. It looks like a tiny ribbon and belongs to a group called flatworms.
- Movement: It glides over surfaces using tiny hairs on its underside and secretes mucus to slide.
- Feeding: Planaria has a mouth in the middle of its body. It extends a tube called a pharynx to suck up food like dead animals or small organisms.
- Reproduction: It can reproduce sexually or asexually. Amazingly, if you cut a Planaria into pieces, each piece can grow into a new worm!
- Special Feature: Known for its ability to regenerate—some can regrow entire bodies from just a small piece.
Summary
- Amoeba moves and eats with pseudopodia and can change shape.
- Paramecium uses cilia to move and feed, and has two nuclei.
- Planaria glides on mucus, feeds through a tube-like pharynx, and can regenerate body parts.
- All three are simple organisms that teach us a lot about life, survival, and biology.
Evaluation
- How does an Amoeba move and eat?
- What structures help Paramecium to swim?
- What is one amazing thing Planaria can do if it is cut into pieces?
- Which of these organisms has two nuclei?
Look at how far you’ve come! From cells to body plans, now you even know about amazing microscopic life. Keep up this wonderful energy and hunger for knowledge. Afrilearn is always here to walk beside you—every lesson, every step. You’ve got this!