BIOL 1000 Chapter Notes - Chapter 1: Ultraviolet, Phototaxis, Circadian Rhythm
Document Summary
Chapter 1, lecture 1: light & life learning objectives: Pigment- a molecule that can absorb photons of light. Absorption spectrum- a plot of the amount of light a pigment absorbs in relation to the wavelength of light. Eyespot- light receptor that allows for sensing of light direction and intensity. Eye- organ used to sense light, important for vision, which distinguishes it from the eye spot. Vision requires the brain to interpret signals sent to the brain from the eye. Melanin- a pigment that strongly absorbs photons of electromagnetic radiation that are in the ultraviolet region of the spectrum. Humans synthesize melanin in a specialized skin cell called melanocytes. People who live in equatorial countries have more melanin in their skin than people who live at higher altitudes. Melanin prevents the ultraviolet radiation from penetrating ours kin and destroying essential b vitamin folate.
