Photosynthesis Explained

• Plants make their own food through photosynthesis, using sunlight and water, unlike other organisms that need to eat.
• Photosynthesis is carried out by plants, some bacteria, and protists.
• Photosynthesis converts energy from sunlight into food.
• Photosynthesis requires sunlight, carbon dioxide, and water.
• The chemical equation for photosynthesis is: 6CO2 + 6H2O -> C6H12O6 + 6O2.
• CO2 represents carbon dioxide.
• H2O represents water.
• C6H12O6 represents glucose.
• O2 represents oxygen.
• Photosynthesis is essentially the reverse of cellular respiration.
• Photosynthesis uses carbon dioxide, water, and sunlight to produce sugars and oxygen.
• Chloroplasts are organelles within plant cells where photosynthesis occurs.
• Chloroplasts are located in leaf cells.
• Chlorophyll is a green pigment found in thylakoid membranes of chloroplasts.
• Chlorophyll in bacteria is found in the plasma membrane.
• A pigment is a compound that absorbs specific wavelengths of visible light.
• The electromagnetic spectrum includes wavelengths from radio waves to gamma rays.
• Chlorophyll and other pigments absorb specific visible wavelengths.
• Visible light has wavelengths ranging from 700 nm (red) to 400 nm (blue).
• Shorter wavelengths have higher energy, while longer wavelengths have lower energy.
• Chlorophyll absorbs mostly blue and red wavelengths.
• Chlorophyll reflects green wavelengths, which is why plants appear green.
• The color of a pigment is the wavelength of light it reflects.
• Chlorophyll contains electrons at a ground state.
• When chlorophyll absorbs light energy, electrons jump to an excited state.
• Excited electrons are transferred from chlorophyll to a primary electron acceptor.
• Chlorophyll becomes oxidized during this process.
• Accessory pigments absorb other wavelengths of light and pass energy to chlorophyll.
• Accessory pigments expand the range of wavelengths that can be used for photosynthesis.

Photosynthesis is how plants, bacteria, and protists convert light energy into chemical energy. The process uses sunlight, carbon dioxide, and water to produce sugars and oxygen. Chloroplasts and chlorophyll play key roles in this vital process.