Associated membrane protein types are lipopolysaccharide selective barriers. Biological membranes include cell membranes, outer coverings of cells or organelles that allow passage of certain proteins and nuclear membranes, which cover a cell nucleus; and tissue membranes, such as mucosae and serosae. ,Platelets, also called thrombocytes or cloth cells in blood and are needed to stop bleeding by clumping and clotting the blood the vessels when the an injury occurs. Teh bone marrow will produce the platelets that have no nucleus. Platelates are unique to mammals, the are curved shaped 1900nm to 3100 nm large nucleus free clothing structures.