Biology 1002B Lecture Notes - Lecture 2: Channelrhodopsin, Photoisomerization, Photochemistry
Document Summary
Bio 1002b - lecture 2 - trapping light. Ribosomes = where protein synthesis occurs: some are free in cell, others are attached to endoplasmic reticulum, proteins synthesized by er ribosomes are found in er, proteins synthesized by free cytosolic ribosomes are found in cytosol. Difficult to distinguish between er and nuclear envelope. Chlorophyll has two possible excited states for electrons. Energy of blue photon takes electron to higher excited state: heat loss drops it to lower excited state in 10-12 seconds. Energy of red photon takes electron to lower excited state. What happens to excited electron after: energy can be lost as heat, fluorescence pigment can emit photon of light. Photon is of longer wavelength (less energy) because of some heat loss: photochemistry. Occurs in eyespot, eye, chloroplast using light energy to drive chemical change (oxidation reaction: energy transfer. Excited state (energy) of one pigment transferred to next nearby pigment molecule. Note: energy is transferred, not electron itself.
