an amber-colored, protein-rich liquid that separates out when blood coagulates.
any of the muscular-walled tubes forming part of the circulation system by which blood (mainly that which has been oxygenated) is conveyed from the heart to all parts of the body.
a member of a large group of unicellular microorganisms that have cell walls but lack organelles and an organized nucleus, including some that can cause disease.
a bacterium, virus, or other microorganism that can cause disease.
resistant to a particular infection or toxin owing to the presence of specific antibodies or sensitized white blood cells.
an image produced on a sensitive plate or film by X-rays, gamma rays, or similar radiation, and typically used in medical examination.
an organism that lives in or on another organism (its host) and benefits by deriving nutrients at the host's expense.
organs and glands in the body that are responsible for digestion.
is the organ system that protects the body from various kinds of damage, such as loss of water or abrasion from outside.
a red protein responsible for transporting oxygen in the blood of vertebrates. Its molecule comprises four subunits, each containing an iron atom bound to a heme group.
the system that circulates blood and lymph through the body, consisting of the heart, blood vessels, blood, lymph, and the lymphatic vessels and glands.
agent that kills or inhibits the growth of microorganisms on the external surfaces of the body.
is the set of organs that allows a person to breathe and exchange oxygen and carbon dioxide throughout the body.
any of the fine branching blood vessels that form a network between the arterioles and venules.
contain the pigment hemoglobin, which imparts the red color to blood, and transport oxygen and carbon dioxide to and from the tissues.
a threadlike structure of nucleic acids and protein found in the nucleus of most living cells, carrying genetic information in the form of genes.
combine chemically with substances that the body recognizes as alien, such as bacteria, viruses, and foreign substances in the blood.