Natural resources are classified as renewable and nonrenewable. what is the difference between the two?

Basically, humans use lot's of energy for heating, lighting, movement, and machines, that energy has come from and energy source. Some sources are renewable, and some are None-Renewable. In general as a Non-Renewable source are fossil fuels. These come from under the ground meaning that there not usable. There can be a fixed amount of coal, oil, and gas in the world and when we use this energy then its gone and there is no coming back.

  -Hope this helps .

the glands which are associated with each description is given below:

pancreas - is an endocrine and exocrine gland that secretes juices with enzymes for digestion. salivary glands- with protection and digestion in the mouth. liver- secretes bile for digestion.   lachrymal glands - secrete tears to moisten eyes and protect them from particles and infection.   sweat gland -regulates water, salt, and temperature. oil glands - to form a protective barrier on the skin.   goblet cells - secrete mucus for protection.