Photosynthesis & Cellular Respiration

• Reactants of one process....

• ... are the products of the other process

Energy renewal

• Energy captured from sunlight by photosynthetic organisms is used and released in the cellular respiration of living things

• The energy that living things use, must continually be renewed through photosynthesis

Why is Photosynthesis so important?

• We must obtain glucose from plants

• Plants are the first step in the food chain

• The oxygen released during photosynthesis is necessary for many organisms.

​What Can Limit Photosynthesis?

• ​Amount of sunlight

• ​Amount of Carbon dioxide

• ​Temperature

Cellular Respiration

• Once solar energy is converted to chemical energy by photosynthesis, it has to be changed to a form that can be used by the organism

• Cellular respiration is the process that releases energy by breaking down food molecules in the presence of oxygen

Photosynthesis vs Cellular Respiration

Notice the order:

​

Photosynthesis - ETC then Calvin Cycle

​

Cellular Respiration - Kreb's Cycle then ETC

Photosynthesis vs Cellular Respiration

• Photosynthesis stores energy into glucose - Cellular Respiration releases energy from glucose

• Photosynthesis removes carbon dioxide and respiration returns it