Question

These organisms of Protista are found moving along decaying twigs and leaves.
A. Desmids
B. Diatoms
C. Euglenoids
D. Slime moulds

Answer 1

Hint: Protists are simple eukaryotic organisms that are neither animals nor plants or fungi. Protists are unicellular in nature but also exist as a colony of cells. Most protists reside in water, damp terrestrial ecosystems, or even as parasites.

Complete step-by-step answer:
The term ‘Protista’ derives from the Greek word “protistos”, which means “the very first“. These organisms are generally unicellular, and the cell of these organisms comprises a nucleus that is bound to the organelles. Some of them even have structures that aid locomotion such as cilia or flagella. A few organisms that belong to the kingdom Protista have pseudopodia that help them to move. Protists comprise an enormous collection of single-celled and multicellular organisms that contain a nucleus. They also have highly specialised cellular machinery known as cell organelles that help in carrying out various life processes. Most protists are free-living autotrophs (like algae) whereas others are heterotrophic (Amoeba) or even parasitic (Trypanosoma protozoa). Some examples of protists are Euglena, Plasmodium,Paramecium, Amoeba, etc. Protists are categorised into five subdivisions depending on their general distinctive features. They are categorised as Protozoans, Slime moulds, Euglenoids, Dinoflagellates, and Chrysophytes.
Slime moulds are saprophytic organisms (they consume decaying and dead material). These are small organisms that have multiple nuclei. Generally, Slime moulds are characterised by the presence of aggregates known as a plasmodium and are even visible to the naked eye.

Therefore the correct answer is option D.

Note: Protista reproduces by asexual methods. The sexual method of reproduction is very rare and takes place just during times of stress. Amoebas are examples of protists that move around using pseudopodia.