An excess of which of the following would most likely be associated with the formation of a dead zone?

• Carbon
• Oxygen
• Nitrogen
• Iron

Which of the following is not a source of nitrogen and phosphorous to a river?

• Fertilizers
• Animal waste
• Wastewater 
• Burning fossil fuels 

Tags

NGSS.HS-LS2-7

What does DO stand for?

• Dissolved oxygen
• Dissolved osmium
• Dissolved ozone 

Tags

NGSS.HS-LS2-3

The term hypoxic means...

• DO content is less than 2 mg/L, but is still above zero
• DO content is 0 mg/L
• DO content is greater than 2 mg/L
• DO content is 6 mg/L

Typically, dissolved oxygen is expressed as 

• milligrams per milliliter
• pounds per liter
• grams per liter
• milligrams per liter

This term refers to an ecological imbalance caused by excess nutrients

• Eutrophication
• Nitrification
• Decomposition
• Photosynthesis

Which of the following correctly expresses the relationship between decomposition and dissolved oxygen?

• Decomposition releases dissolved oxygen into the water
• Decomposition uses dissolved oxygen, removing it from the water
• Decomposition does not require dissolved oxygen
• Decomposition creates dissolved oxygen 

Which of the following DO content would be considered "normal" and supportive of marine life?

• 0 mg/L
• 1 mg/L
• 6 mg/L
• 2 mg/L

Tags

NGSS.HS-LS1-7

NGSS.HS-LS2-3

The term "anoxic" refers to an absence of what?

• carbon
• nitrogen
• oxygen
• phosphorous 

Tags

NGSS.HS-LS2-3

True or false: dead zones can occur in both fresh and marine waters around the world. 

• True
• False 

Tags

NGSS.HS-ESS3-1

NGSS.HS-LS2-6

NGSS.HS-LS2-7