Why is light needed for photosynthesis

As its area is broad, the lamina helps in the absorption of sunlight and carbon dioxide during photosynthesis. Photosynthesis takes place in the chloroplasts that have chlorophyll present in them. It is the chlorophyll that absorbs light energy from the sun.

There are tiny pores called stomata that function as roadways for carbon dioxide to enter and oxygen to leave the plant. Did you know that the colour of light plays an important role during photosynthesis? Yes, it does. Plants use only certain colours from light for the process of photosynthesis. The chlorophyll absorbs blue, red and violet light rays. Photosynthesis occurs more in blue and red light rays and less, or not at all, in green light rays.

The light that is absorbed the best is blue, so this shows the highest rate of photosynthesis, after which comes red light. Green light cannot be absorbed by the plant, and thus cannot be used for photosynthesis. Chlorophyll looks green because it absorbs red and blue light, making these colours unavailable to be seen by our eyes. It is the green light which is not absorbed that finally reaches our eyes, making the chlorophyll appear green.

This can happen because light energy is used to split water. The products of this reaction are oxygen yeah for us heterotrophs! The hydrogen ions are used to make the ATP mentioned earlier.

Here is a video showing the formation of oxygen in the light reaction. Video from: Noel Pauller. ATP molecules provide energy for the synthetic reactions during dark reaction of photosynthesis and are converted into ADP molecules. ADP molecules, thus, formed during dark reaction are reconverted into ATP molecules during light reaction. Light is, thus, necessary for the process of photosynthesis to provide energy for the synthetic reactions.

Do not sell my personal information. Cookie Settings Accept. Manage consent. Close Privacy Overview This website uses cookies to improve your experience while you navigate through the website.

Out of these, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities of the website.

We also use third-party cookies that help us analyze and understand how you use this website. These cookies will be stored in your browser only with your consent. You also have the option to opt-out of these cookies. But opting out of some of these cookies may affect your browsing experience.

Necessary Necessary. Necessary cookies are absolutely essential for the website to function properly. These cookies ensure basic functionalities and security features of the website, anonymously.

The cookie is used to store the user consent for the cookies in the category "Analytics". The cookies is used to store the user consent for the cookies in the category "Necessary". We can see that the role of sunlight is extremely important.

The sun is the source of almost all energy on Earth. It enables plants and other organisms to turn water and carbon dioxide into sugars through a process called photosynthesis. The sun releases light that travels many millions of miles through space. A unit of that light is known as a photon. Photons have properties of both particles and waves. The energy of a photon determines the color of light it emits.

The higher the energy, the smaller the wavelength. Wavelengths are measured in nm, or nanometers. One nanometer is one billionth of a meter. Humans can only see a portion of all emitted light. The visible light spectrum ranges from roughly to nanometer wide wavelengths. Plants absorb light and store energy from it. They tend to absorb red and blue light, but they do not absorb green light. Green light bounces back off of the leaves. That is part of why we perceive plants as green.

Inside of the plant's leaves are organelles known as chloroplasts. Chloroplasts have parts called thylakoids. The thylakoids stack up inside chloroplasts like how you would stack plates.

Chloroplasts also contain chlorophyll. The two main types of chlorophyll are chlorophyll A and B. They are pigments that absorb specific wavelengths of light. Chlorophyll A can absorb blue, violet, red, and orange light.