Class Notes (807,843)
Canada (492,871)
Biology (976)
BI110 (458)

lecture 1.docx

6 Pages
Unlock Document

Wilfrid Laurier University
Matthew Smith

Interaction b/w Light and Matter:  Shorter wavelength = higher energy and vice versa  The sun is the reason for life on earth What is light?  Electromagnetic radiation that humans detect w/ eyes  Wave of discrete particles are photons  Wavelength is distance b/w two successive peaks  Light energy must be absorbed by molecules (pigments) in order to be used  Pigment molecules absorb wavelengths of light (know similarities)  Conjugated system: o Alternating singl-/double bonds o Delocalization of e (at atomic level, electrons are absorbing the light; by being delocalized, electrons are more able to absorb light) o o Some are able to absorb multiple wavelengths o When chlorophyll molecule isn't exposed to light, it is at its ground state o When introduced to light, it gets promoted to a higher level of energy o o The amount of energy in red wavelength of light, matches the difference from ground state to first level of energy o Amount of energy in blue wavelength of light, matches the difference from ground state to second level of energy  Essentially, the amount of energy in a wavelength of light matches the difference from the ground state (0) to its excited state o Blue light is a shorter wavelength with higher energy levels o Red has a longer wavelength than blue o Electrons in the first stage of excitation will not absorb blue light due to imbalance in energy  After being promoted to the first stage of excitation, the electron falls back down
More Less

Related notes for BI110

Log In


Don't have an account?

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.