oxyy

which process returns oxygen to the atmosphere?

• photosynthesis

• respiration

• condensation

which photo represent the oxygen cycle?

• 
• 
• 

the oxygen gas is about_______of the air we breath

• 21%

• 1%

• 78%

in respiration animals take in ________

• carbon dioxide

• oxygen

• nitrogen

the carbon dioxide is less than_______of the air we breath

• 32%

• 1%

• 78%

in respiration animals release__________

• nitrogen

• oxygen

• carbon dioxide

around how much of the human body is composed with oxygen?

• 57%

• 21%

• 75%

• 65%

choose the sources of oxygen______

• respiration

• photosynthesis

• oxygen

• carbon dioxide

which biotic process is common to the carbon and oxygen cycle??

• transpiration

• diffusion

• respiration

plants use__________to make their own food during photosynthesis

• co2

• water

• co2 , water , energy from the sun

• energy from the sun