The Carbon Cycle

The Carbon Cycle

Marcia Valdivieso

The carbon cycle describes how carbon moves between the atmosphere, soils, living creatures, the ocean, and human sources. The carbon cycle is the process that moves carbon between plants, animals, microbes, minerals, the earth, and the atmosphere.

​

What is the Carbon Cycle?

Multiple Choice

What inorganic molecule is carbon normally found in?

• Carbon Dioxide

• Nitrogen

• Oxygen

• Hydrogen

Carbon can be stored in a variety of reservoirs, including plants and animals. Carbon is used by plants to build leaves and stems, which are then digested by animals and used for cellular growth.

​

Where is Carbon Stored?

Multiple Choice

Where do primary consumers get the carbon from?

• cellular respiration

• photosynthesis

• eating plants

• nitrogen fixing bacteria

Nature tends to keep carbon levels balanced, meaning that the amount of carbon naturally released from reservoirs is equal to the amount that is naturally absorbed by reservoirs.​ humans have upset this balance by burning fossil fuels, which has added more carbon to the atmosphere than usual and led to climate change and global warming.

Carbon Balance

Multiple Choice

How have humans effected the Carbon Cycle?

• Recycling

• composting

• burning fossil fuels

• using electric cars

Multiple Select

What environmental changes have the carbon cycle led to?

• climate change

• earthquakes

• tsunamis

• global warming

Most carbon is stored in rocks and sediments, while the rest is stored in the ocean, atmosphere, and living organisms. These are the reservoirs, or sinks, through which carbon cycles. The ocean is a giant carbon sink that absorbs carbon. Some of the four main ones are oceans (the largest reservoir), geological reserves of fossil fuels, the terrestrial surface (plants and soil, mainly), and the atmosphere.

​

Carbon Reservoirs

Multiple Choice

Which of the boxes represents a carbon source in the image?

• b

• a

• c

• d

Multiple Choice

Which box represents a carbon sink that holds carbon compounds for the shortest period of time?

• a

• b

• c

• d

Multiple Choice

Which of the following biogeochemical cycles includes the processes of buffering ocean ph and photosynthesis, as shown in the diagram?

• the nitrogen cycle

• the phosphorus cycle

• cellular respiration

• the carbon cycle

The Nitrogen Cycle

Nitrogen Cycle is a biogeochemical process through which nitrogen is converted into many forms, consecutively passing from the atmosphere to the soil to organism and back into the atmosphere.

​

What is the Nitrogen Cycle?

It involves several processes such as nitrogen fixation, nitrification, denitrification, decay and putrefaction. Nitrogen fixation is nitrogen gas that is converted into organic nitrogen compounds.

​

Nitrogen Cycle Processes

The largest reservoir of nitrogen is found in the atmosphere, mostly as nitrogen gas (N₂). Nitrogen gas makes up 78% of the air we breathe. Most nitrogen enters ecosystems via certain kinds of bacteria in soil and plant roots that convert nitrogen gas into ammonia (NH₃). This process is called nitrogen fixation.

​

Nitrogen Reserviors

Multiple Choice

Which of the following processes is illustrated by the downward arrows from the atmosphere that show the conversion of nitrogen gas into usable forms available to producers?

• nitrogen fixation

• nitrogen assimilation

• photsynethesis

• ammonia

Multiple Choice

The majority of the nitrogen on Earth can be found in which of the following reservoirs?

• sedimentary rock

• the atmosphere

• soil bacteria

• terrestrial plants

Primary Productivity

Primary productivity is the rate at which sunlight is converted into organic compounds via photosynthesis.

​

What is Primary Productivity?

Net primary production (NPP) is the difference between the energy fixed by autotrophs and their respiration. Sunlight is very important for NPP because sunlight provides the necessary energy of carbon to be captured and plants to grow. So more sunlight means higher terrestrial NPP.

​

​Net Productivity

Gross primary productivity is defined as the total rate of photosynthesis in a given area. Producers such as plants use some of this energy for metabolism/cellular respiration and some for growth (building tissues).

​

Gross Primary Productivity

Cellular respiration is the breakdown of organic compounds (sugars) for cellular energy (ATP). This does not require sunlight due to it occurring all the time.

​

Cellular Respiration

Multiple Choice

This rate of reaction can be measured in the dark by determining the amount of oxygen gas consumed in a period of time.

• primary productivity

• cellular respiration

• general primary productivity

• net primary productivity

Multiple Choice

The energy available to consumers determined by subtracting the energy used by plants from the total energy transformed by the process of photosynthesis.

• Net primary productivity
• Secondary productivity
• Tertiary productivity
• Gross primary productivity

Poll

How helpful did you find this mini lesson? :)

• helped me better understand the carbon cycle ☺️

• I am still a little lost on the carbon cycle 🙁