A mixed tideâtwo uneven tides a day, or one high and one lowâis also possible. Tides vary on timescales ranging from hours to years due to a number of factors. To make accurate records, tide gauges at fixed stations measure water level over time.
Top 10 facts about the world. Oligodendrocytes, also known as oligodendroglia, are a type of brain cell in the central nervous system that belongs to the glial cell family. The main purpose of glial cells is maintenance and support of nervous system cells.
This sheath is called the myelin sheath and is made up of Schwann cells in the peripheral nerves and oligodendrocytes in the central nervous system nerves. This insulation can be damaged by compression just as the nerve membrane itself can be injured.he central nervous system nerves are supported by âassistant cellsâ called oligodendrocytes and the peripheral nervous system nerves are support byâ assistant cellsâ called Schwann cells. There are marked differences between the two types of nerves.