Plant Processes: Respiration

8SCIENCE: Tues. Feb. 15

Review: Why is photosynthesis an important plant process?

• Photosynthesis = process of making food • Organisms like plants provide food for almost all other

living things on Earth• Plants release oxygen into atmosphere – almost 90% of

oxygen is from photosynthesis

Respiration

• Related to photosynthesis• Respiration is a series of chemical reactions

that all organisms use to break down food to release energy

• Respiration in most organisms requires oxygen – This is called aerobic respiration– Aerobic means using oxygen

Respiration

Chemical reaction for respiration:C₆H₁₂O₆ + 6O₂ 6CO₂ + 6H₂O + energy Glucose and oxygen produce carbon dioxide and water and energy

• Is this equation familiar? How does it relate to the equation for photosynthesis?

*Remember: During photosynthesis CO₂ and H₂O are combined with light energy to create glucose and O₂. *In respiration oxygen and glucose are combined to release the energy found in the bonds of the food (glucose) and this creates CO₂ and H₂O

Why is respiration important?

• Provides energy needed by the cell and gives energy to the whole organism

• During respiration, food energy is changed into a form that plant cells (and your cells!) can use

• Aerobic respiration returns CO₂ to the atmosphere to be used again in photosynthesis