For the roller coaster, see Sewer Rat (roller coaster) . The brown rat, also referred to as common rat, street rat, sewer rat, Hanover rat, Norway rat, brown Norway rat, Norwegian rat, or wharf rat (Rattus norvegicus) is one of the best known and most common rats.he brown rat is a rather large true murid and can weigh twice as much as a black rat and many times more than a house mouse. The length is commonly in the range of 20 to 25 cm (8 to 10 in), with the tail a further 18 to 25 cm (7 to 10 in), thus being roughly the same length as the body.
Jaundice is the medical term that describes yellowing of the skin and eyes. This condition forms when there is too much bilirubin in your system. Bilirubin is a yellow pigment that is formed by the breakdown of dead red blood cells in the liver. Normally, the liver gets rid of bilirubin along with old red blood cells. Jaundice may indicate a serious problem with the function of your liver, gallbladder, or pancreas. Find an internist near you Â».
Albinism, for example, is an inherited condition that causes a lack of pigment. So people with albinism typically have light skin, white or pale yellow hair, and light blue or gray eyes. Another condition called vitilgo, creates smooth, depigmented white spots on the skin. Vitilgo affects nearly 2% of the population, but it strikes people between 10 and 30 years old more often, and is more evident in people with darker skin.