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.
LEM or L.E.M. dirt bikes and ATVs are gasoline powered little motocycles or ATVs designed for kids up to 12 years old. They have all the same features as full size motorcycles for adults. LEM mainly only makes 50cc 2-stroke off road vehicles, but over the years LEM also produced a 65cc 2 stroke and a 110cc 4 stroke ATV and dirt bike. ATV Parts.