Cycles and Ecology Review

Biogeochemical Review
+ some Ecology at the end

Based on questions from the quiz tbh

Multiple Choice

Why is understanding the carbon cycle important for addressing environmental issues?

• It helps us understand climate change and global warming.

• It explains the process of photosynthesis only.

• It is only relevant to plant biology.

• It has no impact on human activities.

Multiple Choice

Which of the following is considered a carbon sink in the carbon cycle?

• Atmosphere

• Fossil fuels

• Ocean (algae & sediments)

• Animal agriculture

Multiple Choice

Which of the following is considered a carbon sink in the carbon cycle?

• Igneous rocks

• Forests

• Atmosphere

• Animal agriculture

Multiple Choice

Which of the following is considered a carbon source in the carbon cycle?

• Planting trees

• Photosynthesis

• Using electric vehicles

• Comustion of fossil fuels

Multiple Choice

Which of the following is considered a carbon source in the carbon cycle?

• Deforestation

• Photosynthesis

• Respiration

Multiple Choice

Which process in the carbon cycle is responsible for releasing stored energy by breaking down glucose?

• Photosynthesis

• Respiration

• Sedimentation

• Burial

Multiple Select

Which of the following processes are involved in the exchange of carbon between the atmosphere and the ocean?

• CO2 dissolving in and out of ocean

• Respiration by algae

• Combustion of fossil fuels

• Sedimentation of organic matter on ocean floor

Multiple Select

Which of the following processes are involved in the exchange of carbon between the atmosphere and the ocean?

• Deforestation

• Algae and photosynthesis

• Combustion of fossil fuels

• Decomposition by bacteria

Open Ended

Explain how the extraction and combustion of fossil fuels impact the concentration of CO2 in the atmosphere. Remember: anthropogenic sources mean they are from human activities. It is a GREAT word to use on your AP exam FRQs!

Sequestered Carbon

Sequester means it is stored- in carbon sinks.

If CO2 is removed from the atmosphere and stored, that carbon is being sequestered.

• For example, planting more trees helps remove CO2 from the atmosphere, so we can say forests help sequester carbon, and in turn help mitigate climate change.

Multiple Choice

How does burning fossil fuels contribute to the net increase in atmospheric carbon?

• Burning fossil fuels creates smoke and haze which blocks the sun and slows photosynthesis

• Carbon is released from newly planted forests as part of photosynthesis

• Carbon that has been sequestered underground is added to carbon cycle

• Burning fossil fuels releases CO2 that is absorbed to the atmosphere faster than natural CO2

Multiple Choice

Why is nitrogen so essential for plants and animals?

• Required for lipids and cellular membranes

• Required to make proteins and DNA

• idk tbh

• Required to make organelles in the cells

Multiple Choice

Which process in the nitrogen cycle converts atmospheric nitrogen (N2) into a form usable by plants?

• Nitrification

• Denitrification

• Nitrogen fixation

• Assimilation

Multiple Choice

Before: nutrient poor field was abandoned and an invasive plant took over

After: field is cleared of vegetation and soil has excess nitrogen

What happened?

• The stones in the soil eroded and produced excess nitrogen and phosphorous

• Nitrogen leached from an excess of plant fertilizer

• The invasive plants were able to fix nitrogen and produced excess nitrogen in their leaves

• The invasive plant had root nodules that fixed N2 into soil

Multiple Choice

Which of the following steps in the nitrogen cycle involves plants taking in nitrogen in the form of ammonium and nitrate to create proteins and DNA in their bodies

• Assimilation

• Nitrification

• Ammonification

• Denitrification

Multiple Choice

Which process in the nitrogen cycle converts a nitrogen compound in the soil back to atmospheric nitrogen

• Nitrification

• Denitrification

• Nitrogen fixation

• Assimilation

Multiple Select

Main source of nitrate leaching due to human activities?

• High rates of precipitation

• Plants used all the nitrogen and left phosphorous behind

• Overabundance of Nitrogen and Phosphorus from synthetic fertilizers

• Rock was eroded, releasing phosphorous

Multiple Select

Which of the following are impacts of human activities on the nitrogen cycle?

• Increased greenhouse gas emissions

• Eutrophication of water bodies

• Decreased nitrogen fixation

• Nitrate leaching

Open Ended

Explain why phosphorus is considered a limiting nutrient in many ecosystems and describe the consequences of this limitation.

Multiple Choice

Which of the following is a major reservoir of phosphorus in the phosphorus cycle?

• Atmosphere

• Rocks and sediments

• Living organisms

• Oceans

Multiple Select

Which of the following are natural and synthetic sources of phosphorus in the environment?

• Weathering of rocks

• Phosphorous being soluble in water

• Synthetic fertilizers

• Atmospheric deposition

​Phosphorous Cycle

The ONLY biogeochemical cycle WITHOUT a gaseous component!

Multiple Choice

What is the primary reason phosphorus does not cycle through the atmosphere like carbon or nitrogen?

• Phosphorus is too reactive

• Phosphorus does not have a gaseous phase

• Phosphorus is only found in living organisms

• Phosphorus is only found in water

Multiple Choice

What is the primary cause of eutrophication in aquatic ecosystems?

• Excessive nutrients from fertilizers

• Overfishing

• Increased sunlight

• Low temperatures

Open Ended

Describe the process of eutrophication and explain how excess phosphorus contributes to this phenomenon in aquatic ecosystems.

Multiple Choice

Which process in the water cycle is responsible for moving water from plant leaves to the atmosphere?

• Transpiration

• Condensation

• Precipitation

• Infiltration

Multiple Choice

Generalized pyramid energy flow has only a 10% efficiency because 90% of the energy is lost to the environment as heat. This phenomenon is explained by

• a. the second law of thermodynamics

• b. the law of limiting factors

• c. the law of conservation of matter

• d. the greenhouse effect

Multiple Choice

In the energy pyramid here, how much of the energy in each level gets lost as heat or used by the organism for survival?

• 80%
• 90%
• 10%
• 20%

Multiple Choice

In a given ecosystem, producers convert solar energy into 15,000kcal of chemical energy stored in organic compounds. Which of the following is the most likely amount of energy available to primary consumers?

• 1.5 Kcal

• 150 kcal

• 1,500 kcal

• 13,500 kcal

Multiple Choice

If producers capture 80,000 J of energy from the sun, how much will be passed on to the secondary consumers?

• 8,000 J

• 800 J

• 80 J

• 8 J

Multiple Choice

If producers capture 65,000 J of energy from the sun, how much will be passed on to the tertiary consumers?

• 6,500 J

• 650 J

• 65 J

• 6.5 J

Multiple Choice

If producers capture 55,000 J of energy from the sun, how much will be passed on to the primary consumers?

• 5,500 J

• 550 J

• 55 J

• 5.5 J

Multiple Choice

Eat primary consumers (can be carnivores and omnivores)

• Tertiary Consumers
• Secondary Consumers
• Quaternary Consumers 
• Top Predators 

Multiple Choice

An organism that uses an outside source of energy like the sun to create energy-rich food molecules.

• Consumer
• Producer
• Decomposer
• Parasite 

Multiple Choice

In the food web shown, the snail would be considered...

• primary consumer
• secondary consumer
• tertiary consumer
• producer

Multiple Choice

Ecological efficiency from one trophic level to the next is generally:

• 1%

• 10%

• 75%

• 90%

Multiple Choice

The diagram below shows the cycling of nutrients in an ecosystem.
The removal of which of the following groups would cause an immediate decrease in the amount of energy flowing through the system?

• Producers
• Consumers
• Decomposers
• Inorganic nutrients

Open Ended

Explain how a trophic cascade would occur in this food web if the grasshoppers were eradicated.