The functions of the atmosphere today are

sustaining life with oxygen
filtering harmful rays from the sun
to protect earth from meteor collisions
removes nutrients from the soil
keeps the earth's climate unstable

Match the digestive enzymes to the macro molecules they to digest. down fats into glycerol and fatty acids down carbohydrates into simple sugars down nucleic acids into nitrogenous bases and simple sugars down proteins into amino acids

The carbon cycle is best defined as a process in which a. carbon changes from inorganic forms to organic forms and back b. carbon is changed into other elements such as oxygen or nitrogen c. carbon is continually created from the sun’s energy by plants d. carbon is consumed and regenerated from other elements such as oxygen and nitrogen

Which statement describes a way in which the digestive and excretory systems work together? a. the nephrons absorb nutrients from food going to the large intestine. b. the excretory system balances blood gases in the small intestine. c. the intestinal villi filter blood and send wastes to the bladder. d. the excretory system balances the salts and water obtained from digested food