Capillary

Capillaries contain a single layer of endothelial cells and their basement membrane. The lumen of capillaries is so narrow that red blood cells have to pass in single file. The thin walls of capillaries facilitate exchange of gases and small molecules between the bloodstream and surrounding tissue. In which type of tissue does this capillary reside? Which enzyme would you expect to find on the surface of these endothelial cells? Hint: which macromolecule do adipocytes want from plasma?