Question

(unicellular vs metazoan), use no more than a few short sentences to speculate why one organism might encode the protein (or a similar family member to that identified in question 1) and another may not.

Your reasoning should include reference to the type of protein and how it works in general terms.

Answer 1

Eukaryotic cell are different from prokaryotes. One of the main differences lies in the presence of compartmentalized organelles in eukaryotes. The genetic material DNA lies in the nucleus as opposed to naked in cytoplasm in prokaryotes.

All the prokaryotes are unicellular whereas some eukaryotes like protists, specific fungi and algae are also unicellular. Metazoans are a division in animal kingdom that comprises of all animals with exceptions of protozoans and sponges. Metazoans are therefore multicellular animals with differentiated tissues and organ systems.

The evolution of muticellular animals from unicellular ancestors is an enigma. The organization of multi cellular organisms require secretions and response to cell adhesion and signaling proteins. Unicellular eukaryotes can act as a bridge to explain this gap. Choanoflagellates (unicellular eukaryote) have the ability to move, adhere and to respond to signals.

The multi cellular organisms should possess ability for cellular differentiation, to undrgo cell cycle, signaling by receptor tyrosine kinases and cell adhesion for the organism to develop.