• Autotrophs: Organisms that produce their own organic food molecules using energy from light or chemical bonds.
• Overall Equation: \(6\text{CO}_2 + 6\text{H}_2\text{O} + \text{light energy} \rightarrow \text{C}_6\text{H}_{12}\text{O}_6 + 6\text{O}_2\)
• Site of Photosynthesis: Organ: Leaf | Organelle: Chloroplast
The Two Main Stages
1. Light-Dependent Reactions:
• Location: Thylakoid membranes (labeled X in the diagram).
• Reactant used: Water (\(\text{H}_2\text{O}\)).
• Products made: Oxygen (\(\text{O}_{2}\)), ATP, and NADPH.
2. Calvin Cycle (Light-Independent Reactions):
• Location: Stroma.
• Reactant used: Carbon dioxide (\(\text{CO}_{2}\)).
• Products made: Glucose (\(\text{C}_6\text{H}_{12}\text{O}_6\)), ADP, and \(\text{NADP}^{+}\).
Reactant & Product Tracking
• Source of Carbon in Glucose: Carbon dioxide (\(\text{CO}_{2}\)).
• Source of Hydrogen in Glucose: Water (\(\text{H}_2\text{O}\)).
• Source of Released Oxygen Gas (\(\text{O}_{2}\)): Water (\(\text{H}_2\text{O}\)).
• Glucose Storage: Excess glucose is stored as starch.
• Glucose Transport: Moved through the plant via phloem tissue.
Light & Pigments
• Light-Capturing Molecule: Chlorophyll.
• Most Effective Light Colors: Blue and Red.
• Least Effective Light Color: Green (it is reflected, which is why leaves look green).
Leaf Anatomy & Gas Exchange
• Cuticle: Waxy, waterproof outer layer that prevents water loss.
• Stomata: Microscopic pores that control gas exchange (\(\text{CO}_{2}\) in, \(\text{O}_{2}\)/water vapor out).
• Guard Cells: Cells that physically open and close the stomata.
• Xylem: Vascular tissue that transports water up from roots to leaves.
• Root Hairs: Hair-like extensions that increase surface area for water absorption.
Effect of Open Stomata:
• Photosynthesis: Increases (more \(\text{CO}_{2}\) enters).
• Transpiration (Water Loss): Increases (water vapor escapes).
• Plant Water Levels: Decreases.
• Chlorophyll / Chloroplast Levels: Stays the same.
🔋 Part 2: Cellular Respiration Master Sheet
Core Formula & Concepts
• Overall Aerobic Equation: \(\text{C}_6\text{H}_{12}\text{O}_6 + 6\text{O}_2 \rightarrow 6\text{CO}_2 + 6\text{H}_2\text{O} + \text{ATP}\)
• Primary Energy Source: Glucose.
• Primary Useful Product: ATP (used directly for cellular work like active transport and muscle contraction).
• Waste Products: Carbon dioxide (\(\text{CO}_{2}\)) and Water (\(\text{H}_2\text{O}\)).
The Three Aerobic Stages (In Order)
1. Glycolysis:
• Location: Cytoplasm.
• Details: Splits glucose into pyruvate. Does not require oxygen.
2. Krebs Cycle (Citric Acid Cycle):
• Location: Mitochondrial Matrix.
• Details: Breaks down pyruvate, releases \(\text{CO}_{2}\), and charges electron carriers (NADH and \(\text{FADH}_{2}\)).
3. Electron Transport Chain (ETC):
• Location: Inner Mitochondrial Membrane (cristae).
• Details: Yields the greatest amount of ATP. Uses Oxygen (\(\text{O}_{2}\)) as the final electron/hydrogen acceptor to form water.
Cellular Respiration Atom Tracking
• Where the Carbons from Glucose end up: \(\text{CO}_{2}\).
• Where the Hydrogens/Electrons from Glucose end up: \(\text{H}_2\text{O}\).
🏃 Part 3: Anaerobic Pathways, Exercise, & Redox
Anaerobic Respiration (Fermentation)
• Definition: Breakdown of glucose to generate ATP without oxygen.
• Location: Cytoplasm.
• ATP Yield Comparison: Aerobic respiration yields 36–38 ATP | Anaerobic respiration yields only 2 ATP.
• Main Purpose of Fermentation: Regenerates \(\text{NAD}^{+}\) so glycolysis can keep running.
• Lactic Acid Fermentation: Occurs in animals. Produces lactic acid.
• Alcohol Fermentation: Occurs in yeast/plants. Produces ethanol and \(\text{CO}_{2}\).
Chemical Changes During Strenuous Exercise
• ATP: Decreases (used up rapidly).
• ADP: Increases (byproduct of breaking down ATP).
• Glucose: Decreases (consumed as fuel).
• \(\text{CO}_{2}\): Increases (waste product builds up).
• Lactic Acid: Increases (due to a lack of oxygen causing a switch to fermentation).
Redox Reactions (Electrons & Hydrogen)
• Oxidation: The loss of electrons or hydrogen atoms.
• Reduction: The gain of electrons or hydrogen atoms.
• Memory Trick: OIL RIG (Oxidation Is Loss, Reduction Is Gain).
🔄 Part 4: Plants vs. Animals (The Big Picture)
Plant Gas Concentrations in a Sealed Container
• In the Light: \(\text{CO}_{2}\) decreases. (Photosynthesis runs faster than respiration, consuming \(\text{CO}_{2}\)).
• In the Dark: \(\text{CO}_{2}\) increases. (Photosynthesis stops without light, but respiration continues, releasing \(\text{CO}_{2}\)).
Comparing Organisms
• Plants/Autotrophs: Perform both photosynthesis and cellular respiration.
• Animals/Heterotrophs: Perform only cellular respiration.
• Plant Roots: Perform only cellular respiration (they have no access to light and lack chloroplasts).
• Plant Leaves: Perform both photosynthesis and cellular respiration.
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