The annelid worm Glycera dibranchiata has an oxygen binding protein with the same folding pattern as myoglobin. Myoglobins and hemoglobins occur sporadically among invertebrate phyla. It is hard to see a clear, common line of decent from a single ancestor for these species let alone annelids, insects, and vertebrates. No other known protein form has oxygen binding capability. How might these observations best be explained.

protocol for imps extraction focusing on membrane protein extraction, solubilisation, and purification.

"a.) well–developed vascular system."

thrombocytopenia, which is a deficiency in blood platelets, can cause bleeding and bruising in the dermis similar to senile purpura. other possible causes include: exposure to ultraviolet rays and aging skin are common causes of senile purpura. senile purpura may also be a sign of collagen loss in the skin and bones.