Table of contents

1. A Review of General Chemistry5h 5m
2. Molecular Representations1h 14m
3. Acids and Bases2h 46m
4. Alkanes and Cycloalkanes4h 17m
5. Chirality3h 39m
6. Thermodynamics and Kinetics1h 22m
7. Substitution Reactions1h 48m
8. Elimination Reactions2h 30m
9. Alkenes and Alkynes2h 9m
10. Addition Reactions3h 19m
11. Radical Reactions1h 58m
12. Alcohols, Ethers, Epoxides and Thiols2h 42m
13. Alcohols and Carbonyl Compounds2h 17m
14. Synthetic Techniques1h 26m
15. Analytical Techniques:IR, NMR, Mass Spect7h 3m
16. Conjugated Systems6h 13m
17. Ultraviolet Spectroscopy51m
18. Aromaticity2h 34m
19. Reactions of Aromatics: EAS and Beyond5h 1m
20. Phenols55m
21. Aldehydes and Ketones: Nucleophilic Addition4h 56m
22. Carboxylic Acid Derivatives: NAS2h 51m
23. The Chemistry of Thioesters, Phophate Ester and Phosphate Anhydrides1h 10m
24. Enolate Chemistry: Reactions at the Alpha-Carbon1h 53m
25. Condensation Chemistry2h 9m
26. Amines1h 43m
27. Heterocycles2h 0m
28. Carbohydrates5h 53m
29. Amino Acids4h 20m
30. Peptides and Proteins2h 42m
31. Catalysis in Organic Reactions1h 30m
32. Lipids 2h 50m
33. The Organic Chemistry of Metabolic Pathways2h 52m
34. Nucleic Acids1h 32m
35. Transition Metals6h 14m
36. Synthetic Polymers1h 49m

3. Acids and Bases

Organic Chemistry Reactions

Organic Chemistry

3. Acids and Bases

Organic Chemistry Reactions

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Multiple Choice

In the process of photosynthesis, where do the electrons entering Photosystem II originate from?

Carbon dioxide

Glucose

NADPH

Water molecules

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Verified step by step guidance

Understand the role of Photosystem II in photosynthesis: Photosystem II is the first protein complex in the light-dependent reactions of oxygenic photosynthesis. It captures photons and uses the energy to extract electrons from water molecules.

Identify the source of electrons: In the light-dependent reactions, water molecules are split in a process known as photolysis. This process occurs in the thylakoid membranes of chloroplasts.

Explain photolysis: Photolysis is the process by which water molecules are split into oxygen, protons, and electrons. The chemical equation for this process is: 2H₂O → 4H⁺ + 4e⁻ + O₂.

Connect photolysis to Photosystem II: The electrons released from the splitting of water molecules are transferred to Photosystem II. These electrons replace the electrons that are excited and lost from the chlorophyll molecules in Photosystem II when they absorb light energy.

Summarize the electron flow: The electrons from water molecules are essential for the continuation of the light-dependent reactions, as they are used to reduce NADP⁺ to NADPH and contribute to the formation of ATP, both of which are used in the Calvin cycle to synthesize glucose.