How does vaccination work?
antibodies from donated blood are injected into the body.
a strong form of the disease is injected under the skin.
o a weakened form of the disease is inhaled through the nose.
medication that fights the disease is injected into the bloodstream.

The greenhouse effect a. something that has occurred for millions of years b. an unnatural phenomenon caused by humans that maintains earths temperature range. c. the results of the differences in the angle of the suns rays d. an unnatural phenomenon that causes heat energy to be radiated back into the atmosphere