Asteroids are celestial rocky bodies that orbit the sun. It was Sir William Herschel who first coined the term âasteroidâ (Greek for star-like) in 1802. He thought that Ceres and Pallas, discovered in 1801 by Giuseppe Piazzi and Heinrich Olbers respectively, were too small and were remnants of a destroyed planet.
blood cell. n. Any of the cells contained in blood; an erythrocyte or leukocyte; a blood corpuscle. blood cell. n. (Physiology) any of the cells that circulate in the blood. See erythrocyte, leucocyte.
White Blood Cells (Leukocytes). A type of immune cell. Most white blood cells are made in the bone marrow and are found in the blood and lymph tissue. White blood cells help the body fight infections and other diseases. Granulocytes, monocytes, and lymphocytes are white blood cells.