Photosynthesis

Photosynthesis

Plant cells use photosynthesis to make food, which the cells can then use as a source of chemical energy. Photosynthesis transforms light energy from the Sun into the chemical energy provided by food.

Light energy is used to power photosynthesis. In plant cells, light energy is captured by chlorophyll, and then used to rearrange the atoms in carbon dioxide and water during photosynthesis.

Chemical energy is released by cellular respiration. This chemical energy is provided by food molecules such as sugars. It is used after cellular respiration to directly power cell growth and other cell processes.

Plant cells need light energy to perform photosynthesis. So first, chlorophyll captures light energy. Photosynthesis uses light energy to make sugars and oxygen from carbon dioxide and water. Photosynthesis starts with carbon dioxide and water and ends with sugars and oxygen.The atoms found in the molecules at the start are rearranged to form the molecules at the end.

Cellular respiration releases chemical energy from the sugars created during photosynthesis. Cellular respiration breaks down the sugars to release chemical energy.After sugars are made, plant cells can use them as a source of energy. Cellular respiration rearranges the atoms of sugars to release chemical energy. After cellular respiration releases chemical energy, the chemical energy is used to power processes such as cell growth.

Photosynthetic Organisms

Organisms that carry out photosynthesis are called photosynthetic organisms. During photosynthesis, these organisms use light energy, carbon dioxide, and water to produce sugars and oxygen.

Photosynthetic organisms also often have the following characteristics:

• They are producers, which are organisms that make their own food inside their cells. Because producers make their own food, they typically do not eat other organisms.

• Their cells contain chloroplasts, which are cell structures where photosynthesis occurs.

• Their chloroplasts often contain a green substance called chlorophyll.

• Chlorophyll captures light energy from the Sun to power photosynthesis.

• They use the sugars they produce during photosynthesis as food. This food provides energy that helps the organisms live, grow, and reproduce.