BIO 1109 Midterm: Bio 1000 Midterm Notes.docx
Document Summary
Photon can only be absorbed if photon energy = | ground state excited state : eye > mechanism to sense light, vision: interprets information, cone: colour, rod: sensitive > dim light, chlorophyll a & b: absorption of light, pigments: molecules that are good at absorbing photons. Light as a source of information: photoreceptor: light sensing system, most common in nature > rhodopsin, each rhodopsin molecule = protein opsin bonded to pigment retinal, photoreceptors are cells (have basic organelles, rods > disk > light absorbing > rhodopsin here, absorption of photon > retinal changes shape > triggers changes in opsin > triggers other stuff, retinal cis > kink in conformation. Strived because of selection: region without photoreceptors > our blind spot, having two eyes compensates for this, optic nerve creates this by going through the retina, bacteria do not have histones (basic proteins found in chromatin, positively charged)
