September 12th, 2012
Chapter 1: Light & Life
Green Algae
• Chlamyodomonas Reinhardtii – common algae
• Uses light for both energy and info
• Eyespot: Light sensor
• Responds by moving closer and farther away
• Toward (not intense) forward (intense) to use light as source of energy
• Chloroplast uses it as a source of energy
The Sun
• Reason for life on earth
• Optimal distance from sun to use as energy
• Energy comes from conversion of matter
• Producing electromagnetic radiation
• Many kinds of electromagnetic radiation
• Short and long wavelength have different levels of electromagnetic energy
• Shorter = high energy, Longer = low energy
• Visible wavelength (400-700nm) visible to us
What is Light?
• Photons: discrete packet of energy
• Waves of photon = light
• Light: electromagnetic radiation that humans can detect with eyes
• Wavelength: distance between two successive peaks
• Pigment: molecules that absorbs light so that it can be used
• Associates with matter (light + pigment interaction)
Bacteriorhodospin
• Membrane protein bound to a molecule
• Allows halobacteria to use light as energy
• Proton (H+) pump
The Eye
• What distinguishes eye of an anima from eyespot of green algae C.
Reinhardtii
• Human eyes are image forming
Vision
• Requires brain to interpret images
Chapter 1: Light & Life
Green Algae
• Chlamyodomonas Reinhardtii – common algae
• Uses light for both energy and info
• Eyespot: Light sensor
• Responds by moving closer and farther away
• Toward (not intense) forward (intense) to use light as source of energy
• Chloroplast uses it as a source of energy
The Sun
• Reason for life on earth
• Optimal distance from sun to use as energy
• Energy comes from conversion of matter
• Producing electromagnetic radiation
• Many kinds of electromagnetic radiation
• Short and long wavelength have different levels of electromagnetic energy
• Shorter = high energy, Longer = low energy
• Visible wavelength (400-700nm) visible to us
What is Light?
• Photons: discrete packet of energy
• Waves of photon = light
• Light: electromagnetic radiation that humans can detect with eyes
• Wavelength: distance between two successive peaks
• Pigment: molecules that absorbs light so that it can be used
• Associates with matter (light + pigment interaction)
Bacteriorhodospin
• Membrane protein bound to a molecule
• Allows halobacteria to use light as energy
• Proton (H+) pump
The Eye
• What distinguishes eye of an anima from eyespot of green algae C.
Reinhardtii
• Human eyes are image forming
Vision
• Requires brain to interpret images
