Serum (blood) Serum (blood) In blood, the serum () is the component that is neither a blood cell (serum does not contain white blood cells- leukocytes, or red blood cells- erythrocytes), nor a clotting factor; it is the blood plasma not including the fibrinogens. Serum includes all proteins not used in blood clotting and all the electrolytes, antibodies, antigens, hormones, and any exogenous substances (e.g., drugs and microorganisms). The study of serum is serology. Serum is used in numerous diagnostic tests, as well as blood typing. Measurements of serum concentrations has proved useful in many fields including clinical trials of therapeutic vs
Mucus mucus has a threefold higher potential to limit agent penetration than purified mucus. Mucus Mucus ( ) is a polymer. It is a slippery aqueous secretion produced by, and covering, mucous membranes. It is typically produced from cells found in mucous glands, although it may also originate from mixed glands, which contain both serous and mucous cells. It is a viscous colloid containing inorganic salts, antiseptic enzymes (such as lysozymes), immunoglobulins, and glycoproteins such as lactoferrin and mucins, which are produced by goblet cells in the mucous membranes and submucosal glands. Mucus serves to protect epithelial cells (that line the