Question

Dinoflagellates have a mesokaryotic cell organization. Which of the following features is not related to such cellular organization?
A.Single nuclear membrane
B.No spindle formation
C.Presence of histones
D.Permanently condensed chromosomes

Answer 1

Hint: Dinoflagellates are single-celled mesokaryotic which belong to the phylum Dinoflagellata. Their characteristic features make them fall between the category of primitive and advanced type of cells.

Complete answer:
Mesokaryotes are those organisms that were considered between the nucleoid of the prokaryotes (primitive cell type) and nucleus of the eukaryotes (advanced cell type). Their nucleus consists of a new special family of protein called nucleoproteins. Let us analyze the options to find out the correct option.

Option A: Dinoflagellates were earlier termed as prokaryotic but later known to be advanced types of organisms. They are known to have a single nuclear membrane which is one of their characteristic features. Therefore, this is the incorrect option.

Option B: No spindle formation takes place in these organisms which marks a characteristic feature of these mesokaryotes. Therefore, this is the incorrect option.

Option C: Dinoflagellates do not have the presence of histone proteins in them just like prokaryotes. Therefore, this is the correct option.

Option D: The chromosomes of these organisms remain permanently condensed throughout the interphase. This is another characteristic property of dinoflagellates. Therefore, this is the incorrect option.

Hence, the correct answer is option (C)

Note: Histone proteins are basic proteins mainly found in eukaryotic cells nuclei. Histones pack and order DNA into structural units called nucleosomes.