Question

How are cellular respiration and photosynthesis part of the carbon cycle?

Answer 1

Carbon, a chemical element, is essential to all life forms. It is one of the key components of the earth’s atmosphere, biosphere, hydrosphere, and lithosphere. It cycles through all these spheres. Photosynthesis and cellular respiration both partake in the carbon cycle. One process utilizes the atmospheric carbon and one releases carbon as a byproduct.

Complete answer:
-Green plants and certain organisms can utilize sunlight to prepare their food. They use carbon dioxide and water as their raw material to produce sugar. The byproduct of this entire process is oxygen. The process is possible because of a pigment called chlorophyll.
-Photosynthesis in plants involves two phases, the light-dependent phase, and the light-independent phase. Both phrases occur in the chloroplast. The light-dependent phase occurs in the thylakoid membrane of the chloroplast. The light-independent phase occurs in the stroma of the chloroplast.
In the light-dependent phase, the light is absorbed by the photosynthetic pigment (chlorophyll) and other accessory molecules. Water is split to give oxygen as a byproduct. A part of this oxygen is used up by the plants for its cellular respiration. The rest is released into the atmosphere.
-Other organisms require oxygen for their survival. This oxygen is used up in various metabolic processes, to ultimately produce the energy-rich molecule ATP. The food that animals consume and the oxygen from the atmosphere are acted upon by enzymes. Nutrients and energy produced are utilized by the body. This is called cellular respiration. Carbon dioxide produced during cellular respiration is released out of the body.
-This way both plants and animals help replenish the carbon in the environment.

Note: Not all organisms respire in the presence of oxygen. These organisms are called anaerobes. Anaerobic respiration also contributes to the carbon cycle.
Aquatic organisms (phytoplankton) cannot use atmospheric carbon to perform photosynthesis. They utilized dissolved carbonates to meet their carbon requirements. Weathering of rocks such as limestone gives out bicarbonates. These bicarbonates find their way to the water bodies.