REACTIONS OF PHOTOSYNTHESIS 8-3 http://vilenski.org/science/safari/cellstructure/chloroplasts.html REACTIONS OF PHOTOSYNTHESIS 8-3 http://www.science.siu.edu/plant-biology/PLB117/JPEGs%20CD/0076.JPG

Remember from CELL BIO CHLOROPLASTS Enzymes for PHOTOSYNTHESIS are in the ________________ CHLOROPLASTS http://www.science.siu.edu/plant-biology/PLB117/JPEGs%20CD/0076.JPG

See a video clip about the LIGHT-DEPENDENT REACTION (Part 1) 8C

PHOTOSYNTHESIS HAPPENS IN CHLOROPLASTS THYLAKOIDS = sac-like photosynthetic = stack of thylakoids membranes inside chloroplast GRANUM (pl. grana) Image from BIOLOGY by Miller and Levine; Prentice Hall Publishing©2006

SPACES THYLAKOID SPACE STROMA cytoplasm Gel-filled space inside chloroplast surrounding thylakoid sac Gel-filled space Inside the thylakoid sac cytoplasm Gel-filled space OUTSIDE chloroplast but inside the cell membrane http://www.science.siu.edu/plant-biology/PLB117/JPEGs%20CD/0076.JPG

PHOTOSYNTHESIS HAPPENS IN CHLOROPLASTS Proteins that are part of the thylakoid membrane organize ________________________________ into clusters called _____________________ Light absorbing PIGMENTS PHOTOSYSTEMS http://www.science.siu.edu/plant-biology/PLB117/JPEGs%20CD/0076.JPG

LIVING THINGS NEED ENERGY CARRIERS Molecule that carries = _______ Molecule that carries HIGH ENERGY ELECTRONS = ___________ ATP NADP+ Images by Riedell

HIGH ENERGY ELECTRONS require a special carrier, too Frying pan image from: BIOLOGY by Miller and Levine; Prentice Hall Publishing©2006 HIGH ENERGY ELECTRONS require a special carrier, too ____________ is one of the carriers that cells use to transport high energy electrons. NADP+ ________ + _____ + _____ → ____________ 2 e- H+ _______= nicotinamide adenine dinucleotide phosphate

PHOTOSYNTHESIS Light-Dependent Reaction Oxygen Light & Water ATP NADPH SUGAR (CH2O)n Carbon Dioxide Light-Independent Reactions

LIGHT-DEPENDENT REACTIONS INSIDE THYLAKOID SPACE ATP SYNTHASE ↓ PHOTOSYSTEM II ↓ ELECTRON TRANSPORT SYSTEM ↓ PHOTOSYSTEM I OUTSIDE THYLAKOID IN STROMA Image modified from: Pearson Education Inc; Publishing as Pearson Prentice Hall

↓ ↓ WHY DOES PHOTOSYSTEM II COME BEFORE PHOTOSYSTEM I? It was discovered and named 1st PHOTOSYSTEM II ↓ ↓ PHOTOSYSTEM I Image modified from: Pearson Education Inc; Publishing as Pearson Prentice Hall

See a video clip about the LIGHT-DEPENDENT REACTION (Part 2) 8D

REMEMBER CELL BIO Molecules move automatically from http://www.newtonswindow.com/problem-solving.htm REMEMBER CELL BIO Molecules move automatically from “where there’s A LOT” to “where there’s NOT” Animatioin from: http://www.biologycorner.com/resources/diffusion-animated.gif

http://www.newtonswindow.com/problem-solving.htm REMEMBER CELL BIO Diffusion happens anytime there is a difference in concentration in one place compared to another = ________________________ CONCENTRATION GRADIENT

REMEMBER CELL BIO Diffusion can happen across membranes TOO http://www.newtonswindow.com/problem-solving.htm REMEMBER CELL BIO Diffusion can happen across membranes TOO …as long as membrane will let molecule through

LIGHT-DEPENDENT REACTIONS Pearson Education Inc; Publishing as Pearson Prentice Hall LIGHT-DEPENDENT REACTIONS SEE A MOVIE ATP SYNTHASE IN ACTION See an animation about the ELECTRON TRANSPORT CHAIN http://www.stolaf.edu/people/giannini/flashanimat/metabolism/atpsyn1.sw http://www.stolaf.edu/people/giannini/flashanimat/metabolism/photosynthesis.swf

LIGHT DEPENDENT REACTION Requires ______________ Molecules are part of ________________ Made up of __________________ connected by ______________________ & ___________________ Uses light energy to change ADP + P → _______ NADP+ + 2e- + H + → _________ Breaks apart ______ molecules and releases _____________ LIGHT THYLAKOID membranes PHOTOSYSTEMS II & I ELECTRON TRANSPORT CHAIN ATP SYNTHASE ATP NADPH H20 oxygen

PHOTOSYNTHESIS Light-Dependent Reaction Light & Water Oxygen ATP NADPH (CH2O)n Carbon Dioxide Light-Independent Reactions CALVIN CYCLE

PHOTOSYNTHESIS OVERVIEW Pearson Education Inc; Publishing as Prentice Hall

Calvin Cycle CO2 Enters the Cycle Energy Input 5-Carbon Molecules Regenerated 6-Carbon Sugar Produced See Calvin cycle animation Sugars and other compounds

CALVIN CYCLE ____________ require ____________ (also called _________________________) ____________ require ____________ Happens in _________ between thylakoids NADPH donates _______________ ATP donates _________________ CO2 donates ______________ to make __________ LIGHT INDEPENDENT DOES NOT LIGHT STROMA Hydrogen + electrons ENERGY Carbon & oxygen GLUCOSE http://www.estrellamountain.edu/faculty/farabee/biobk/BioBookCHEM2.html

Factors that Affect Photosynthesis AMOUNT OF WATER ____________________ Water is one of the raw materials needed, so A shortage of water can ________________ photosynthesis slow or stop Desert plants and conifers that live in dry conditions have a waxy coating on their leaves to prevent water loss. http://www.hononegah.org/departments/Anderson/cactus.JPG

Factors that Affect Photosynthesis TEMPERATURE Photosynthesis enzymes function best between 0° C - 35° C At temperatures above or below this range, photosynthesis will slow or stop Conifers in winter may carry out photosynthesis only occasionally http://www.sustland.umn.edu/maint/images/evergreen10.jpg

Enzymes work BEST at a certain ___ and __________. REMEMBER CELL BIO Enzymes work BEST at a certain ___ and __________. Conditions that are TOO ACIDIC or TOO HOT cause proteins to unwind or _________ pH temperature DENATURE http://www.desktopfotos.de/Downloads/melt_cd.jpg http://www.nealbrownstudio.com/adm/photo/163_nb_fried_egg.jpg

Denaturing changes the shape of the enzyme making it not work HOMEOSTASIS (keeping pH and temperature constant) is important for maintaining enzyme function. Image from:http://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookCHEM2.html

Factors that Affect Photosynthesis LIGHT INTENSITY ____________________ More light increases rate of photosynthesis up to a certain level until plant reaches its maximum rate of photosynthesis See effect of light experiment http://www.teachnet.ie/foneill/exper.htm http://206.173.89.42/REALTYWITHALOHA_COM/piphoto/funny%20sun%20with%20sunglasses.gif

THE BIG PICTURE sugars PHOTOSYNTHESIS provides the _____________ we breathe and the __________ heterotrophs (like us) consume to survive OXYGEN sugars Carbon dioxide Sugars WATER Oxygen _____________ + ____________ _______________ + ____________

Concept Map Photosynthesis Light- dependent reactions Calvin cycle Section 8-3 Photosynthesis includes Light- dependent reactions Calvin cycle takes place in uses use take place in Thylakoid membranes Stroma NADPH ATP Energy from sunlight to produce of to produce ATP NADPH O2 Chloroplasts High-energy sugars