Question

Which of the following is a phototrophic flagellate?
A. Entamoeba
B. Paramecium
C. Euglena
D. Vorticella

Answer 1

The word flagellate refers to an organism or a cell that has one more appendage called flagella. The term phototroph refers to an organism which obtains their food in form of energy with the help of sunlight to synthesize the organic compounds for the purpose of nutrition. So, phototrophic flagellates are the flagellates that obtain their energy with the help of sunlight.

Complete answer:
Euglena is a genus of unicellular flagellate that belongs to the kingdom Protista. Most species of Euglena consist of photosynthesizing chloroplasts within cells of the body. Due to the presence of chloroplast, they contain a green color pigment called chlorophyll which is responsible for the process of photosynthesis. The process of photosynthesis helps the Euglena to obtain nutrition by breaking down the complex organic material into simpler substances with the help of sunlight. Thus they are called phototrophic flagellate. The mode of nutrition is called autotrophs similar to that of plants. Euglena can obtain nutrition by heterotrophic mode also and can survive without sunlight and feed on peptone, beef extracts, carbohydrates, and ethanol. They are abundant in fresh water and are in sufficient numbers to color the surface as green color.
Entamoeba is an intestinal parasite and mostly causes dysentery. They do not contain chlorophyll and hence are not autotrophic flagellate. Paramecium is a type of ciliated algae. It obtains its food by opening a small hole called a cytostome. Vorticella are eukaryotic ciliates and for obtaining food they have structures called oral cilia.
Therefore, option C is the correct answer.

Note: In a characteristic configuration, flagella are supported by microtubules with nine fused pairs surrounding two central singlets. They come from a basal body. Flagella guides food into a cytostome or mouth in certain flagellates, where food is swallowed. Flagella also supports or includes rods for hair, called mastigonemes. In classifying eukaryotes, their ultrastructure plays a significant role.