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Unit 8: Cellular Respiration and Photosynthesis Key Topics 1. Equations a. Cellular Respiration (CR): C6H12O6+6O2→6CO2+6H2O+Energy (ATP)\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{Energy (ATP)}C6...

Unit 8: Cellular Respiration and Photosynthesis Key Topics 1. Equations a. Cellular Respiration (CR): C6H12O6+6O2→6CO2+6H2O+Energy (ATP)\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{Energy (ATP)}C6 H12 O6 +6O2 →6CO2 +6H2 O+Energy (ATP) b. Photosynthesis (PS): 6CO2+6H2O+light energy→C6H12O6+6O26\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}_26CO2 +6H2 O+light energy→C6 H12 O6 +6O2 2. Aerobic vs. Anaerobic Respiration a. Aerobic: Requires oxygen; produces more ATP. b. Anaerobic: Does not require oxygen; produces less ATP (e.g., lactic acid fermentation). 3. Role of ATP a. ATP is the energy currency of the cell. b. Provides energy for cellular processes like muscle contraction, transport, and biosynthesis. 4. Organelles Critical for CR and PS a. Mitochondria: Site of cellular respiration. b. Chloroplasts: Site of photosynthesis. 5. Experiments a. Phenol Red in the Experiment: i. Used as a pH indicator to detect changes in CO₂ levels. ii. CO₂ production during respiration makes the solution more acidic (color change). b. Exercise and Cellular Respiration: i. Monitored by measuring changes in breathing rate or CO₂ production during physical activity. 6. Role of Light in Photosynthesis a. Light provides energy to excite electrons in chlorophyll, driving the light- dependent reactions of photosynthesis. Unit 9: DNA Preparation for GMO Detection Key Topics 1. GMOs a. Genetically Modified Organisms. b. Created by introducing a foreign gene into an organism's genome. 2. Regulatory Sequence a. A DNA segment that controls gene expression. b. Ensures the inserted gene is expressed in the target organism. 3. Steps to Isolate DNA a. Steps: Grinding sample, Chelex, centrifugation. 4. Chemicals Used: chelex 5. Equipment for DNA Isolation a. Centrifuge, pipettes, microtubes, thermocycler, vortex 6. Supernatant vs. Pellet a. Supernatant: Liquid portion containing DNA. b. Pellet: Solid debris after centrifugation. Unit 10 PCR (Polymerase Chain Reaction) Amplifies specific DNA sequences. Stages: Denaturation: high temperature (94°C) to separate the two DNA strands Annealing: cools the reaction (50-65°C) which allows the primers to bind to complementary sequences in the DNA. Extension: temperature up a little (72°C) so that that Taq polymerase can optimally extend the sequence between the two primers by adding new DNA c. PCR Master Mix Components:  i. Template DNA: Target for amplification. ii. Primers: Define start and end of target DNA (CAMV or NOS) iii. Taq Polymerase: Enzyme for DNA synthesis. iv. dNTPs: Building blocks of DNA. v MgCl 2 – The magnesium is needed as a cofactor for the Taq polymerase. 7. Control Groups a. Negative Control: Contains no DNA; ensures no contamination. b. Positive Control: Contains known target DNA; confirms PCR worked. Primers used: CAMV and NOS 8. Pros and Cons of GMOs a. Pros: Higher yield, pest resistance, enhanced nutrition. b. Cons: Environmental concerns, allergen risks. 9. Stages of Mitosis and Cytokinesis a. Mitosis Stages: Prophase, Metaphase, Anaphase, Telophase. b. Cytokinesis: Division of the cytoplasm. 10. Garlic Root Compounds a. Used for observing cell division under a microscope (mitosis). Unit 11: Gel Electrophoresis for GMO Analysis Key Topics 1. Gel Composition a. Made of agarose (a polysaccharide). 2. Fluorescing Dye a. Commonly ethidium bromide (EtBr) or GelGreen to visualize DNA under UV light. (DNA loading dye) 3. Submersion Solution a. Buffer solution (TAE) Maintains pH and conducts electricity. Equipment Used b. Gel box, power supply, pipettes, UV transilluminator. 4. How Gel Electrophoresis Works  a. DNA fragments are negatively charged. b. Travel toward the positive electrode through the gel. c. Smaller fragments move faster and farther than larger ones. 5. Determining DNA Fragment Sizes a. Compare the sample bands to a DNA ladder (a marker with known fragment sizes).