Question
Question: Which of the following is coenocytic? (A)Vaucheria (b)Pseudomonas (c)Chlamydomonas (d)All o...
Which of the following is coenocytic?
(A)Vaucheria
(b)Pseudomonas
(c)Chlamydomonas
(d)All of the above
Solution
Hint : They belong to the group of yellow-green algae having tubular multinucleate branches without cross walls.
Complete answer :
The coenocytic cells are present in a few of the diverse and unrelated algal groups which include Xanthophyceae (Vaucheria), Rhodophyceae (Griffithsia), and Chlorophyceae (Chara).
Additional information
-Coenocytic cells are the multinucleated cells that lack a transverse cell wall.
-These cells are the result of karyokinesis (nuclear division) without following cytokinesis (cell division).
-The coenocytic cells are also referred to as coenobium having various numbers of cells mostly in the multiple of two.
-The word coenocyte is derived from the Latin word coeno + cyte, which is based on ancient Greek word koinos meaning ‘common’ and kytos meaning ‘fell.
-The algae which have multinucleate organisms and lack transverse walls.
-The coenocytic cell has continuous protoplasmic mass surrounded by only one cell wall.
-Vaucheria shows apical growth from the tip of the filaments which form coenocytes with a large central vacuole pushing against the surrounding cytoplasm.
-On the periphery of the cytoplasm, chloroplasts are located with the nuclei towards the centre.
So, the correct answer is ‘Vaucheria’.
Note: Pseudomonas are gram-negative bacteria present in the soil and detritivores, they are pathogens of various plants and animals. The word Pseudomonas is derived from the Greek word pseudos meaning ‘false’ and monas meaning ‘a single unit’. Chlamydomonas is the green algae which are single-celled and unicellular flagellates. They are widely distributed in freshwater or damp soil rich in ammonium salt. They are also called snow algae as they remain stagnant on freshwater, seawater, or even damp soil.