The formation of insoluble protein strands which forms a mesh during blood coagulation is the change of O fibrinogen to fibrin
O fibrin to fibrinogen
O thrombin to prothrombin
O vitamin K to prothrombin

the answer will be a) proteins i believe

it's c.us forest service

only about ten percent of the energy at one trophic level is passed on to organisms at the next trophic level. the remainder of the energy is used in life processes or lost as heat.