Although definitions of forest vary, they all include which quality? A maximum size of 2,000 acres
A habitat for many kinds of life
Trees planted by humans
A minimum of 10 species of trees

Which best describes red blood cells? a. they are colorless b. they protect against disease-carrying microorganisms c. they transport oxygen throughout the body d. they aid in blood clotting

The breakdown of food is accomplished by enzymes. a. physical b. chemical c. mechanical d. none of the above

Which gas found in the earth's atmosphere greatly impacts the daily range of temperature on earth. a) oxygen b) hydrogen c) nitrogen d) water vapor