BIOL 241 Lecture Notes - Lecture 15: Nicotinamide Adenine Dinucleotide, Cytochrome, Electron Transport Chain

• School: University of Calgary
• Department: Biology
• Course: BIOL 241
• Professor: Robert Allan Edwards, Kenneth Kai- Sing Ng, Mary Reid, William Huddleston, Peter F.Dunfield

Document Summary

Light reactions of photosynthesis start when a photon of light hits any number of specialized coloured molecules within the cells of phototrophs. The a(cid:271)ilit(cid:455) to a(cid:271)sorb light is what gives them colour. When the photon is absorbed by the molecule, electrons in the bond of that pigment jump to a higher energy level, away from the nucleus. This leads to the pigment molecule being excited and it stores energy. This step (cid:272)ha(cid:374)ges light e(cid:374)erg(cid:455) i(cid:374)to pe that"s stored i(cid:374) the (cid:271)o(cid:374)ds of (cid:272)hloroph(cid:455)ll or opsi(cid:374) or other types of pigment molecules. Chloroplasts have 3 membranes; the thylakoid membrane is the most important. The lumen is the inside of the thylakoid (just like how the mitochondria is the matrix). Phototrophs always use some sort of pigment molecule to absorb solar energy. The shorter the wavelength the higher the energy. Bacterial opsin is a cofactor attached in the plasma membrane of h. halobium.