Question

An acellular slime mould is
A. Dictyostelium
B. Fuligo
C. Polysphondylium
D. All of the above

Answer 1

Hint: Slime moulds belong to kingdom Protista and have got this name by the slime structure that they form during their life cycle. They are mostly found in cellular forms but their acellular forms have also been discovered which form a multinucleate diploid amoeboid mass.

Complete answer:
Slime moulds are eukaryotic organisms which live as single cells or as a colony forming multinucleate reproductive structures. They belong to Mycetozoa group which is divided into:
-Dictyostelid – Cellular slime moulds
-Protosteloid – Amoeba like slime bodies that form fruiting bodies for reproduction. They also belong to the cellular slime moulds category.
-Myxomycetes/ Myxogastria – Acellular slime moulds which are plasmodium.
Cellular slime moulds spend their life as single celled structures like that of amoebas when the food resources are abundant but as the food resources are exhausted they aggregate together and form a slimy structure before they start their reproduction. Acellular slime moulds spend their life as a single multinucleate cell which doesn’t have any membrane which differentiates the millions of nuclei present in a single large. This structure is called the plasmodium stage. Fuligo is an acellular slime mould. The other two organisms given in option A and B are also slime moulds but they are cellular slime moulds.

Hence, the correct answer is option (B).

Additional information:
-Fuligo is also known as flowers of tan or scrambled egg slime.
-In the acellular slime moulds the plasmodium forms a fan like structure to which a network of interconnected veins through which the cytoplasm flows is attached.
-Due to multiple veins present these slime moulds can feed on multiple sources at a time.
-These slime moulds feed on dead and decaying material, bacteria and fungi.

Note: The plasmodium structures found in acellular moulds have meristematic activity, can absorb nanoparticles and are photosensitive to light. They are the most preferred microorganism suited to be biosensors.