Question

Nutrition in protists is
A) Holophytic
B) Holozoic
C) Saprozoic
D) All of the above

Answer 1

Hint: As proposed by R.H Whittaker, the animals are classified into five kingdoms ( all unicellular and multicellular). The five kingdoms are as follows:
-Kingdom Monera
-Kingdom Protista
-Kingdom Fungi
-Kingdom Plantae
-Kingdom Animalia


Complete answer:
The question is talking about protists which belong to the kingdom protista. So, we shall study about protista. Kingdom protista contains all the unicellular eukaryotic organisms mainly protozoa and unicellular eukaryotic algae. Some form loose aggregations of cells called colonies. For example, Volvox.

Reproduction in protists maybe sexual by conjugation or zygote formation or asexual through budding, fission and cyst formation. Protists exhibit various means of locomotion through pseudopodia, flagella and cilia. Pseudopodia are the flowing cytoplasmic protrusions of the cell causing movement.it exists in several forms like lobopodia, filopodia, reticulopodia and axopodia. Flagella and cilia are almost similar however cilia are usually shorter than flagella.

Now talking about the modes of nutrition of protists. All types of nutrition occur in protozoa. Some may synthesize their own food from carbon dioxide, nitrates or salts. Some may depend on other sources.

Depending on this the modes are:
-Autotrophic: The protozoans that synthesize their own food from CO₂ and sunlight using chlorophyll. This mode of nutrition is called holophytic nutrition . Example: chlorophyll bearing flagellates.
-Heterotrophic: the organisms that depend on organic or inorganic raw materials.
-Saprozoic: some feed on soluble organic nutrients from their environment and are termed as saprozoic or osmotrophs. Example: parasitic protozoans
-Holozoic: that ingests rigid or solid organic food
-Phagotrophs: that ingests solid food particles of animal or plant origin.

From the above options given, Holophytic, Holozoic,Saprozoic all are present in protists. Therefore, option ‘D’ which is “All of the above” is the correct answer.

Hence the correct answer is option ‘D’.

Note: The characteristics of protists are,
i) They are unicellular and eukaryotic.
ii) They are aquatic.
iii) They can reproduce by both sexual and asexual methods.
iv)They can be heterotrophic, autotrophic and parasitic in nature.