Question

Holozoic unicellular organisms are
A) Amoeba
B) Paramecium
C) Both A and B
D) Fish

Answer 1

Hint: Unicellular organisms are the organisms whose body is made up of single cell. Holozoic nutrition is a kind of nutrition in which the organism engulfs the whole organisms. Protozoans exhibit holozoic nutrition. This type of nutrition is carried out by those organisms which intake solid or liquid as food.

Complete answer:
Holozoic nutrition is a kind of nutrition in which the organism engulfs the whole organisms. It is a type of heterotrophic nutrition. In this the organisms ingests the food through the invagination or pseudopodia of the body. This invagination engulfs the food particle within itself. The organisms further secrete digestive juices to break down the engulfed food and obtain nutrition for growth and development.

Protozoans like amoeba, paramecium exhibit holozoic nutrition. These organisms are unicellular eukaryotes. The steps followed for holozoic nutrition are ingestion, digestion, absorption, assimilation, egestion. The amoeba uses pseudopodia to engulf around food whereas paramecium uses cilia to intake food along with water in its mouth.Fish also undergo holozoic nutrition but are not a unicellular organism. It has a definite body made up of numerous specialised cells and tissues.

Thus, the correct answer is option C.

Note: Amoeba is a unicellular eukaryote which does not have a definite shape. This organism has the tendency to alter its shape by the help of pseudopodia. Pseudopodia not only helps in movement but also helps in engulfing food. Paramecium is a shoe shaped organism which has several cilia around its body. This cilium helps in locomotion as well as in ingestion of food.