Question

Which of the following are the characteristics of kingdom Protista?
A) Multicellular organisms whose chromosomes are not enclosed in a nuclear membrane.
B) Unicellular organisms whose chromosomes are not enclosed in a nuclear membrane.
C) Unicellular organisms whose chromosomes are enclosed in a nuclear membrane.
D) Multicellular organisms whose chromosomes are enclosed in a nuclear membrane.

Answer 1

Hint: Kingdom Protista is included by Haeckel into the three kingdom classification system. Protista includes algae, protozoa, slime moulds and fungi, later on, only unicellular eukaryotes were classified into Protista.

Complete answer: Protista are mainly aquatic organisms. Their body is unicellular and eukaryotic. In the eukaryotic cells, a true nucleus, as well as membrane-bound cell organelles, are also present. Ribosomes are present in the cytoplasm of 80 S type, while the ribosomes are present in mitochondria and plastids are of 70 S type. Protists have flagella, cilia and pseudopodia for locomotion. Movement through cilia is much faster than flagella and pseudopodia. In eukaryotes, a flagellum is a tubulin protein that has a 9+2 arrangement. The nutrition in prokaryotes is both autotrophic and heterotrophic. Autotrophs are mainly photoautotrophs and heterotrophic and the mode of nutrition consists of saprobic, parasitic and holozoic. Prokaryotic shows both type of reproduction i.e. sexual as well as asexual. Sexual reproduction consists of isogamous, anisogamous and oogamous type.
They consist of three classes such as photosynthetic Protists, saprophytic Protists and Protozoans. Photosynthetic Protists consist of Dinoflagellates, Diatoms and Euglenoids. Saprophytic Protista consists of slime moulds such as plasmodial and cellular. Protozoans consist of amoeboids, flagellates, ciliates and sporozoans.
Hence, the correct answer is option C.

Note: In isogamous sexual reproduction. morphologically similar gametes are produced. In anisogamous type, morphologically different gametes are produced and the oogamous type of sexual reproduction is the most advanced type.