Class Notes (835,108)
Canada (508,934)
Biology (6,794)
Biology 1002B (1,346)
Tom Haffie (863)
Lecture 6

Lecture 6- Notes.docx

4 Pages
Unlock Document

Biology 1002B
Tom Haffie

Biology 1002B Lecture 6 Energy Transformation 1 - Energy is captured and put into biosphere through photosynthesis - Measure of chlorophyll concentration is equal to number of photosynthetic organisms. - 50% terrestrial 50% aquatic photosynthesis. - Temp has little to do with oceanic photosynthesis - Carbon dioxide converted to glucose for photosynthesis. - This is possible because they use energy from light to drive reduction of CO2 - Reason they use glucose because it has a lot of free energy. - No energy in CO2, can’t get anything out of CO2, no electrons you can get. Oxygen is holding on to them too tight. - C-H bonds are what we need, lots of energy in the molecule, lots of free electron that can be easily removed. - Endergonic process, free energy of products is greater than reactants. Anabolic pathways, overall positive change in free energy. - Water gets oxidized to oxygen. Carbon dioxide gets reduced to glucose. - Photosynthesis can be divided into two parts: ~ Light reactions: producing ATP energy and reducing power in the form of NADPH. NADPH gives up electrons. ~ Calvin cycle: CO2 converted to carbohydrate glucose. Chloroplast Structure: - Highly conserved - Outer and inner membrane - Stroma: aqueous compartment filed with enzymes - Interior membrane organization: thylakoid membrane - Calvin cycle takes place in stroma - Thylakoid is where light reactions take place. - In thylakoid: thylakoid lumen - There is noting uniquely eukaryotic about photosynthesis. - Happened well before eukaryotes formed. Photosynthetic Electron Transport: - In thylakoid membrane - Large supra complexes (protein complexes) - Many proteins come together to make photosystem 1 and 2 and cytochrome complex. - Both PS2 and PS1 have a reaction center surrounded by antenna, chlorophyll molecules in antenna and light gets funneled to reaction entre. The reaction center chlorophyll of PS2 is P680 and of PS1 Is P700. - Photosystem 1 and 2 absorb a photon of light, light is funneled to reaction centers, chlorophylls get oxidized (photochemical event) electron from P680 leaves and travels down electron transport chain to PS1. - Big pool of PQ molecules in membrane to shovel electrons. - PQ would fall apart if too fluid, too rigid, PQ would have trouble travelling rapidly. - P680 is oxidized, gets electron from splitting of water. - When PQ picks up electron from PS2 it becomes negatively charged, hard time to go through membrane, then picks up proton from stroma now neutrally charged. - Proton gets dropped in thylakoid membrane. - pH of lumen becomes very low compared to that of stroma. - Electrochemical gradient created. Can do work with this gradient. Can harvest gradient to do work. Chemiosmosis is how we harvest an electrochemical gradient to do work. - Only way for protons to get back across, must move through ATP synthase (protein
More Less

Related notes for Biology 1002B

Log In


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.