Which of the following organisms exhibits both autotrophic and heterotrophic modes of nutrition?

Correct option is A

The correct answer is (a) Euglena

• Euglena is a unicellular organism that exhibits both autotrophic (photosynthetic) and heterotrophic (ingesting food) modes of nutrition.

• In the presence of light, Euglena can produce its own food through photosynthesis (autotrophic nutrition) using chloroplasts.

• When light is not available, Euglena can switch to heterotrophic nutrition by absorbing organic material from the environment, much like animals.

Information Booster:

• Autotrophic Nutrition: Organisms that can produce their own food from simple substances like carbon dioxide and water. Example: Plants, algae, and some bacteria.
• Heterotrophic Nutrition: Organisms that rely on consuming organic material from other organisms. Examples include animals and fungi.
• Euglena: Euglena is unique in being able to switch between these two nutritional modes depending on environmental conditions. This makes it a mixotroph, which is an organism capable of both autotrophic and heterotrophic nutrition.
• Chloroplasts: Euglena contains chloroplasts which allow it to perform photosynthesis and produce food when light is available.

Additional Information:

(b) Paramecium:

• Paramecium is a heterotrophic organism, which feeds on small microorganisms like bacteria by engulfing them via phagocytosis. It does not perform photosynthesis.

(c) Amoeba:

• Amoeba is also a heterotrophic organism. It engulfs food through phagocytosis and absorbs nutrients from the ingested food, but it does not perform photosynthesis.

(d) Plasmodium:

• Plasmodium is a parasitic organism and does not exhibit autotrophic nutrition. It relies entirely on its host for nutrition and is the causative agent of malaria.