Similarities of Photosynthesis & Respiration

Plants rely on photosynthesis, while living creatures rely on respiration.

Plants and photosynthetic microbes rely on the process of photosynthesis and respiration to survive. Photosynthesis is unique to organisms containing chloroplasts, which are in all plant cells. Respiration is used by every living organism on Earth. Respiration occurs when a food source is converted into energy and released. This energy fuels the processes of creatures without chloroplasts. While both processes obtain energy differently, they have several basic similarities.

Gas Exchange

Both processes involve the exchange of the gases: oxygen and carbon dioxide. Photosynthesis converts usable carbon dioxide into oxygen. Oxygen is used during respiration, which releases carbon dioxide. Carbon dioxide is crucial for photosynthesis. This type of exchange is cyclic. One process relies on the other to function.

Energy Transformation

Photosynthesis and respiration both transform energy. Plants transform sunlight, carbon dioxide and water into energy (glucose) and store the energy. Respiration converts glucose, water, and oxygen into adenosine triphosphate, carbon dioxide and water. Both transformations are chemical changes that permanently alter the energy sources into usable energy.

Adenosine Triphosphate

All organisms produce adenosine triphosphate (ATP). ATP is like a charged battery and powers every function of a cell. ATP is ready to be used any time but depletes over time when used. Organisms must recharge by using glucose. Adenosine triphosphate is essential to both processes and is the smallest form of usable energy.

Electron Transport

Electron transport is identical in photosynthesis and respiration. Electron transport relies on oxygen. Electron transport is a chain of electron carriers in the membrane of the mitochondria. Electrons are passed to oxygen through a series of reactions, and ATP eventually is produced. Essentially, electron transport moves energy from cell to cell.

References

• Biology in Motion: ATP and Energy Storage
• Global Change: A Primer on Photosynthesis and the Functioning of Cells
• VT Aide: Cycle of Photosynthesis & Respiration