Need these for final.?

Question

A significant fraction of Earth's carbon is found in all but which of the following?

a. carbonate

b. carbon dioxide

c. cellulose

d. carbon monoxide

The greatest concentration of nitrogen on the planet Earth is found in

a. living organisms, including bacteria.

b. the atmosphere.

c. soil minerals.

d. fossil fuels.

Nitrogen is released into the atmosphere by

a. nitrogen fixation.

b. denitrification.

c. nitrification.

d. ammonification.

Which plants are planted to increase the amount of nitrogen in the soil?

a. watermelon and cantaloupe vines

b. legumes

c. mints

d. grasses

Plant cells assimilate nitrogen in the form of

a. ammonia and N2.

b. N2 and nitrite.

c. nitrate and ammonia.

d. urea and nitrate.

Answer 1

1) D. carbon monoxide.  it is being consumed as it comes into contact with free oxygen.

2) B. The atmosphere is approximately 80% N2

3) B. Denitrification

4) B. Legumes including alfalfa increase nitrogen content.  

5) D. Urea is a nitrogen form in some firtilizers.