Question

Brief summary of the ecological and biological requirments of the blepharisma species found in pound water. Where is the organism found? is it autotroph or heterotroph? is it a pathogen? if yes, for what organisms? is the organism single celled or colonial etc.(150 words)

Describe similarity and dissimilarity between colonial protists(e.g algae) with multicellular protists(e.g kelp). speculate on how colonial aggregates of cells may have led to multicellulrity.   

Answer 1

It is a unicellular ciliate prosist found in ponds with fresh water and salty lakes too. It is an heterotroph which feeds on decaying matters. They are found on surface of the ponds swimming with algae. They are single celled organisms and are not pathogenic.

The algae is the primary producer of the ecosystem. It is different from multicellular organism in following ways.

• the color of the plastids
• the presence of flagella
• is the cell surrounded by extracellular material? If so, what is that material - organic or inorganic, a continuous wall or a layer of scales)
• motile or not?
• occur singly, in colonies, filaments or exhibit differentiation that would allow them to satisfy the criterion of multi cellularity. Initially they had symbiosis with multicellular organism after which their descendants acquired the property of living as independent multicellular organism.