Medical Dictionary. brachial plexus. noun. Medical Definition of brachial plexus. : a complex network of nerves that is formed chiefly by the lower four cervical nerves and the first thoracic nerve, lies partly within the axilla, and supplies nerves to the chest, shoulder, and arm.
Nonrenewable Sources of Energy. Most of the energy we use comes from fossil fuels, such as coal, natural gas and petroleum. Uranium is another nonrenewable source, but it is not a fossil fuel.Uranium is converted to a fuel and used in nuclear power plants.Once these natural resources are used up, they are gone forever.nergy is the power we use for transportation, for heat and light in our homes and for the manufacture of all kinds of products. There are two sources of energy: renewable and nonrenewable energy.
The movement of wind and water, the heat and light of the sun, the carbohydrates in plants, and the warmth in the Earthâall are energy sources that can supply our needs in a sustainable way. A variety of methods are used to convert these renewable resources into electricity.olar energyâpower from the sunâis a vast and inexhaustible resource that can supply a significant portion of our electricity needs. A range of technologies is used to convert the sunâs energy into electricity, including solar collectors and photovoltaic panels.