Unit 3 Review

Which is NOT a process of the water cycle?

• precipitation
• freezing
• transpiration
• evaporation

The process of plants losing water through their leaves is called ____.

• condensation
• evaporation
• transpiration
• exhaling

What is the most abundant gas in the atmosphere?

• hydrogen
• oxygen
• helium
• nitrogen

Where are denitrifying bacteria found?

• In the soil
• Root nodules
• In dead things
• In the atmosphere

Humans burn fossil fuels and wood, releasing carbon dioxide into the atmosphere. This carbon dioxide is then absorbed by trees for photosynthesis. These processes are contributory to which chemical cycle?

• The carbon cycle

• The water cycle

• The nitrogen cycle

• The phosphorous cycle

How does the human body return carbon to the atmosphere in the carbon cycle?

• Waste products

• Photosynthesis

• Cellular respiration

• Formation of glucose

In the carbon cycle, animals can release carbon back into the cycle through __________ or through __________.

• burning . . . photosynthesis

• fixation . . . decomposition

• decomposition . . . photosynthesis

• respiration . . . decomposition

• respiration . . . photosynthesis

Where does all the carbon in organisms (living things) originate from?

• Earth's atmosphere

• Rocks

• Water

• Soil

What kind of organism takes out the most carbon from the atmosphere?

• Plants

• Bacteria

• Animals

• Humans

Which of the following are some of the major carbon stores on Earth? You can choose multiple answers

• The ocean

• The lithosphere (upper part of Earth's crust)

• The atmosphere