Part of the Electromagnetic spectrum that is Involved in Photosynthesis
Pigments
Carotenoids
Chlorophyll a and Chlorophyll b
References
Light Energy
Photosynthesis
1- Miller and Levine: Biology
2- https://en.wikipedia.org/wiki/Chlorophyll
3- https://en.wikipedia.org/wiki/Carotenoid
- Photosynthesis is the process by which plants and some other organisms use sunlight to synthesize nutrients from carbon dioxide and water.
- Plants are experts at capturing light energy and using it to make sugars through a process called photosynthesis.
- This process begins with the absorption of light by specialized organic molecules, called pigments, that are found in the chloroplasts of plant cells.
- Plants and other photosynthetic organisms, such as certain species of bacteria, gather their required energy to live using the energy of the sun contained within sunlight using pigments
- There are two types of pigments: principal pigments (chlorophyll a) and accessory pigments (carotenoids, chlorophyll, etc).
- These pigments are responsible for the color of the plants.
- They mainly absorb visible light from the electromagnetic spectrum (red, orange, yellow, green, blue
- Light is a form of electromagnetic radiation, a type of energy that travels in waves known as electromagnetic waves.
- Other kinds of electromagnetic radiation that we encounter in our daily lives include radio waves, microwaves, and X-rays.
- Together, all the types of electromagnetic radiation make up the electromagnetic spectrum.
- the white light that we see that comes from the sun is actually a combination of shades of different colors: red, orange, yellow, green, blue, indigo, and violet.
- Carotenoids are group of different pigments. There are over 600 different carotenoids known.
- They are divided into xanthophylls (which contain oxygen) and carotenes (which are hydrocarbons)
- They mainly absorb electromagnetic waves that have a wavelength ranging from 400 - 530 nm (violet, blue, and some shades of green.
- They reflect other wavelengths of visible light, 530 - 750 nm (green, yellow, orange, and red).
- These pigments are responsible of the red and orange colors of the leaves in fall. These colors aren't shown in spring and summer as the chlorophyll pigments dominates the carotenoids.
- The two chlorophyll pigments absorb light very well in the violet region of the electromagnetic spectrum, which has a wavelength ranging from 400 - 450 nm (nanometers).
- Chlorophyll b absorbs blue light very well, while chlorophyll a essentially reflects blue light, which has a wavelength of 450 - 500 nm.
- Both chlorophyll pigments reflect green and yellow light (green light has a wavelength ranging from 500 - 550 nm, while yellow light has a range 550 - 600 nm). This is why plants seem to appear green most of the time.
- The two chlorophyll pigments absorb orange and red light; although the estimated absorption percentage of these two colors are less than the estimated absorption percentage of violet and blue light. Orange light has a wavelength ranging from 650 - 700 nm while red light has a wavelength of 700 - 750 nm.
By: Belal Sabbah
Faysal Bulbul
Ayoub Ibrahim
Amr Marey
Awais