Regulation of iron absorption and transport. Iron for use in synthesis of heme, iron-sulfur centers and other non-heme iron proteins is obtained from the diet and via release of recycled iron from macrophages of the reticuloendothelial system that ingest old and damaged erythrocytes (red blood cells).
Four-stroke oil is more like the oil used in cars but both 2-stroke and 4-stroke oil serve the same purpose - to keep the engine lubricated. Four-stroke dirt bike oil comes in a variety of weights like 10w-40, 20w-50 and so on. It is not mixed with gas.
Types of motorcycles. (Redirected from Dirt bike) Sport bikes, cruisers, scooters, and touring bikes are some of the many types of motorcycles. There are many systems for classifying types of motorcycles, describing how the motorcycles are put to use, or the designer's intent, or some combination of the two. Six main categories are widely recognized: cruiser, sport, touring, standard, dual-purpose, and dirt bike. Sometimes sport touring motorcycles are recognized as a seventh category.