PHOTOSYNTHESIS
Photosynthesis Involves the Use Of light Energy to convert Water (H20) and Carbon Dioxide (CO2) into Oxygen (O2) and High Energy Carbohydrates (sugars, e.g. Glucose) & Starches
The Photosynthesis Equation
PHOTOSYNTHESIS HAPPENS IN CHLOROPLASTS THYLAKOIDS GRANUM (pl. grana) = sac-like photosynthetic = stack of thylakoids membranes inside chloroplast
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
PHOTOSYNTHESIS HAPPENS IN CHLOROPLASTS Proteins that are part of the thylakoid membrane organize ________________________________ into clusters called _____________________ Light absorbing PIGMENTS PHOTOSYSTEMS
Pigments In addition to water, carbon dioxide, and light energy, photosynthesis requires Pigments Chlorophyll is the primary light-absorbing pigment in autotrophs Chlorophyll is found inside chloroplasts
Light and Pigments Light Contains A Mixture Of Wavelengths Different Wavelengths Have Different Colors
Light & Pigments Different pigments absorb different wavelengths of light Energy from light “excites” electrons in the plant’s pigments Excited electrons carry the absorbed energy
PHOTOSYNTHESIS Light-Dependent Reaction Oxygen Light & Water ATP NADPH Light-Independent Reactions
LIGHT-DEPENDENT REACTIONS ATP SYNTHASE INSIDE THYLAKOID SPACE ↓ PHOTOSYSTEM II ↓ ELECTRON TRANSPORT SYSTEM ↓ PHOTOSYSTEM I OUTSIDE THYLAKOID IN STROMA
↓ ↓ WHY DOES PHOTOSYSTEM II COME BEFORE PHOTOSYSTEM I? It was discovered and named 1st PHOTOSYSTEM II ↓ ↓ PHOTOSYSTEM I
REMEMBER DIFFUSION? Molecules move automatically from where there’s A LOT to where there’s NOT
= ________________________ Diffusion happens anytime there is a difference in concentration in one place compared to another = ________________________ CONCENTRATION GRADIENT
LIGHT-DEPENDENT REACTIONS SEE A MOVIE ATP SYNTHASE IN ACTION
LIGHT DEPENDENT REACTION Requires ______________ Pigments that absorb light are part of ____________________________ Made up of ____________________________ connected by ______________________________ & ___________________ Uses light energy to create _______ and _________ 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
Click the image to play the video segment. Calvin Cycle (8E) Click the image to play the video segment. Video 5
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 ____________ LIGHT INDEPENDENT (also called _________________________) ____________ require ____________ Happens in the _________ 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 OXYGEN Carbon dioxide Sugars WATER Oxygen PHOTOSYNTHESIS provides the _____________ we breathe and the __________ heterotrophs (like us) consume to survive OXYGEN sugars Carbon dioxide Sugars WATER Oxygen _____________ + ____________ _______________ + ____________
Concept Map Photosynthesis Section 8-3 includes takes place in uses take place in to produce of to produce
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
SOUTH DAKOTA SCIENCE STANDARDS Chapter 8 - Photosynthesis: The students will be able to: explain the biochemical processes that a plant uses in photosynthesis explain the role ADP-ATP cycle has within the chloroplast of the cell (9-12.L.1.1) explain the light reaction (9-12.L.1.1) explain the steps of photophosphorylation and the Calvin Cycle (9-12.L.1.1)
SOUTH DAKOTA CORE SCIENCE STANDARDS LIFE SCIENCE: Indicator 1: Understand the fundamental structures, functions, classifications, and mechanisms found in living things 9-12.L.1.1. Students are able to relate cellular functions and processes to specialized structures within cells. Photosynthesis and respiration ATP-ADP energy cycle Role of enzymes Mitochondria Chloroplasts
Core High School Life Science Performance Descriptors High school students performing at the ADVANCED level: explain the steps of photophosphorylation and the Calvin Cycle; analyze chemical reaction and chemical processes involved in the Calvin Cycle and Krebs Cycle; predict the function of a given structure; predict how homeostasis is maintained within living systems PROFICIENT level: describe and give examples of chemical reactions required to sustain life (hydrolysis, dehydration synthesis, photosynthesis, cellular respiration, ADP/ATP, role of enzymes); describe the relationship between structure and function explain how homeostasis is maintained within living systems; predict how life systems respond to changes in the environment; BASIC level name chemical reactions required to sustain life (hydrolysis, dehydration synthesis, photosynthesis, cellular respiration, ADP/ATP, role of enzymes); recognize that different structures perform different functions; define homeostasis;
SOUTH DAKOTA ADVANCED SCIENCE STANDARDS LIFE SCIENCE: Indicator 1: Understand the fundamental structures, functions, classifications, and mechanisms found in living things. 9-12.L.1.1A. Students are able to explain the physical and chemical processes of photosynthesis and cell respiration and their importance to plant and animal life. (SYNTHESIS) Examples: photosystems, photophosphorylation, Calvin Cycle and Krebs Cycle
SOUTH DAKOTA ADVANCED STANDARDS LIFE SCIENCE Indicator 1: Understand the fundamental structures, functions, classifications, and mechanisms found in living things. 9-12.L.1.2A. (Synthesis) Describe how living systems use biofeedback mechanisms to maintain homeostasis. 9-12.L.1.4A. (Application) Identify factors that change the rates of enzyme catalyzed reactions.