Gen Bio 1 L6: Light-dependent Reactions of Photosynthesis P1

• Visible Light: a fraction of the enormous amount of electromagnetic (solar energy) emitted by the sun which can be seen by humans.
• Light Energy: a form of electromagnetic radiation that travels in waves.
• Light Energy: composed of tiny particles called photons.
• Energy of the Light: determined by the measurement of its wavelength, with shorter wavelengths carrying more energy than longer wavelengths.
• Wavelength: measured from crest to crest.
• Electromagnetic Spectrum: the range of all possible frequencies of radiation.
• The difference between wavelengths relates to the amount of energy carried by them.
• Frequency and energy are congruent.
• Visible Light Spectrum: ranges from violet (shorter wavelength, higher energy) to red (longer wavelength, lower energy)
• Violet - 400nm
• Blue - 450nm
• Light Blue: 500nm
• Green: 550nm
• Yellow: 600nm
• Orange: 650nm
• Red: 700nm
• The higher-energy waves can penetrate tissues and damage cells and DNA, explaining why both X rays and UV rays can be harmful to organisms.
• Pigments: molecules that absorb specific wavelengths of light.
• Chlorophyll: primary pigment involved in photosynthesis of plants, which is responsible for the green color of leaves.
• Chlorophyll: absorbs light most efficiently in the blue and red regions of the visible spectrum, while reflecting green light.
• Light Energy: initiates the process of photosynthesis when pigments absorb the light.
• Organic Pigments, whether in the human retina or the chloroplast thylakoid, have narrow range of energy levels that they can absorb.
• Retinal Pigment: can only "see" (absorb) 700nm to 400nm light, the visible light.
• Plant Pigment Molecules: absorb only light in the same range of wavelength (700nm to 400 nm), which plant physiologists refer to as range of photosynthetically active radiation.
• Violet's Wavelength: 380nm - 450nm
• Blue's Wavelength: 450nm - 485nm
• Cyan's Wavelength: 485nm - 500nm
• Green's Wavelength: 500nm - 565nm
• Yellow's Wavelength: 565nm - 590nm
• Orange's Wavelength: 590nm - 625nm
• Red's Wavelength: 625nm - 750nm
• Violet's Frequency: 670THz - 790THz
• Blue's Frequency: 620THz - 670THz
• Cyan's Frequency: 600THz - 620THz
• Green's Frequency: 530THz - 600THz
• Yellow's Frequency: 510THz - 530THz
• Orange's Frequency: 480THz - 510THz
• Red's Frequency: 400THz - 480THz
• Violet's Photon Energy: 2.75eV - 3.26eV
• Blue's Photon Energy: 2.56eV - 2.75eV