Photosynthetic Protists - Euglenoids

Description:

The general characteristics of euglenoids are as follows −

Habits and Habitats

• Occur in fresh water habitats and damp soils.

• Can swim actively in a liquid medium with the help of their long flagellum.

• They can perform creeping movement by expansion and contraction movements of their body. This phenomenon is known as metabody.

• They are mixotrophic in nutrition i.e. they can perform both holophytic and saprobic mode of nutrition.

• Store carbohydrates as paramylon or paramylum bodies.

Structure

• Unicellular flagellated protists.

• Without cellulose cell wall.

• Body is covered by thin flexible pellicle.

• Presence of osmoregulatory contractile vacuole occur in the anterior part of the cell.

• Photosynthetic pigments include chlorophyll a and chlorophyll b.

• A single large nucleus lies in the middle.

Reproduction

• Sexual reproduction has not yet been found in euglenoids.

• Under favourable conditions they may multiply by binary fission.