BIO200H5 Lecture 3: LESSON 3--Photosynthesis
Document Summary
Process by which light energy is captured and channeled into the production of food molecules. This occurs in specialized organelles in plants called chloroplasts (this has structure containing light-sensitive pigments called chlorophyll) Cells just below epidermal layer; small and abundant circles seen in palisade mesophyll cells. Appears like miniature cells with a outer membrane contain stacks of membrane disks: disks are called thylakoids (embedded with protein), grouped in columns each called granum. Of thylakoid is called lumen, connected together by fat bands lamellae: all of these structure are suspended in an aqueous medium called stroma. Pigments absorb light energy at certain electromagnetic wavelength depending on color. Chlorophyll a and b absorb light at blue-violet and red wavelengths (400-500 and 600-700nm) and reflect green wavelengths. Only a can absorb energy and transfer electrons for photosynthesis, b absorbs energy and pass e- to a.
