Euglena Model

Quick Answer: The euglena model is an enlarged representation of Euglena, a single-celled freshwater protist with a flagellum, an eyespot and chloroplasts. A euglena model is used in biology lessons to show how one cell can both photosynthesise like a plant and move and feed like an animal.

Plant or Animal?

Euglena is the classic organism for the question of where plants end and animals begin. It contains chloroplasts and makes food by photosynthesis in the light, yet it swims with a flagellum, senses light with an eyespot and, kept in darkness, can absorb dissolved organic food from the water. This mixed, or mixotrophic, nutrition is why older textbooks listed Euglena under both kingdoms and why it is now placed among the protists.

The body is spindle-shaped and covered by a flexible pellicle of protein strips rather than a cellulose wall, so the cell can change shape in a wriggling motion called euglenoid movement. At the front a flask-shaped reservoir opens to the outside; the long flagellum emerges from it, and beside it lie a red eyespot and a contractile vacuole. Chloroplasts, paramylon granules that store food and a central nucleus fill the rest of the cell.

Whether this is a whole-cell or a sectioned model, its size and its mounting are not stated in the listing. Its value lies in showing structures such as the eyespot and reservoir, which are tiny in a living cell.

Where Euglena Fits in the Syllabus

• Classification lessons on why protists form a separate kingdom
• Comparing modes of nutrition: autotrophic, heterotrophic and mixotrophic
• Showing how a single cell detects light and swims towards it (phototaxis)
• Preparing for examination of pond water or green scum samples under the microscope

Care & Handling

• Hold the euglena model away from its slender flagellum, the part most likely to bend or break.
• Dust with a soft dry brush and keep liquids away from the painted chloroplasts and labels.
• Store it in its box or under cover when not in use.

Specifications

Why Choose LabEquip

Biology teachers often buy the euglena, amoeba and paramecium models together so students can compare three ways of life at the single-cell level. LabEquip lists all three in its biology lab products, including the amoeba model. Use the contact page for quantities.

Frequently Asked Questions

Is Euglena a plant or an animal?

Neither. It has chloroplasts like a plant but moves with a flagellum and can feed on organic matter like an animal. Modern classification places it among the protists, in the group called euglenids.

What is the eyespot for?

The red eyespot, or stigma, shades a light-sensitive swelling at the base of the flagellum. As the cell rotates, the shading changes, which lets Euglena detect the direction of light and swim towards it for photosynthesis.

How does Euglena move?

Mainly by beating its long flagellum, which pulls the cell through the water. It can also change shape by flexing its pellicle, a creeping motion known as euglenoid movement or metaboly.

What is paramylon?

Paramylon is a starch-like carbohydrate stored as granules in the cytoplasm of Euglena. It is the product of photosynthesis kept as a food reserve, and unlike plant starch it does not turn blue-black with iodine.

What happens to Euglena kept in the dark?

It stops photosynthesising and survives by absorbing dissolved organic nutrients from the water. Its chloroplasts shrink back to small undeveloped plastids, which turn green again when light returns.

Why does Euglena have a contractile vacuole?

Like other freshwater protists it gains water by osmosis. The contractile vacuole near the reservoir collects the excess water and discharges it so that the cell does not swell and burst.

Last Updated: September 2026