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.
Electricity is a secondary energy source which means it is produced from primary energy sources such as oil, gas, nuclear energy, wind, coal, solar, etc.enewable source of energy is referring only to the type of what we call the primary source of energy which is either r â¦ enewable like solar or exhaustible like coal or oil. Electricity is a secondary source of energy which depends on the primary source of energy for its production.