Science Lessons Exploring Life - PDF

Update your response by this document Lesson 01.01 Exploring Life What is Science? Science explores the natural world through observation and experimentation. It seeks to answer questions using evidence and logic. For example: Scientists study how plants grow under different conditions to under...

Update your response by this document Lesson 01.01 Exploring Life What is Science? Science explores the natural world through observation and experimentation. It seeks to answer questions using evidence and logic. For example: Scientists study how plants grow under different conditions to understand photosynthesis. Researchers test medicines to see if they are effective against diseases. Science involves developing hypotheses, theories, and laws based on data: A hypothesis is an educated guess (e.g., "Plants grow faster with more sunlight"). A theory explains why something happens (e.g., the Theory of Evolution explains how species adapt). A law describes what happens (e.g., Newton’s Law of Gravity describes how objects fall). Science vs. Pseudoscience Science relies on evidence, repeatable experiments, and testable hypotheses. For example: The Germ Theory of Disease explains how bacteria and viruses cause illnesses. Climate change science uses data from temperature records, ice cores, and atmospheric measurements. Pseudoscience lacks evidence and cannot be tested. Examples include: Astrology claims that star positions affect personality but cannot be proven scientifically. Crystal healing lacks empirical support for its health claims. What Questions Can Science Answer? Science answers questions about observable and measurable phenomena: "How do vaccines work?" "What causes earthquakes?" It cannot answer questions about opinions or beliefs, such as:  "What is the meaning of life?" "Is this painting beautiful?" The Scientific Method 1. Ask a question: Why does my plant wilt? 2. Do background research: Plants need water and sunlight to survive. 3. Form a hypothesis: The plant wilts because it isn’t getting enough water. 4. Test the hypothesis: Water one plant daily and leave another unwatered. 5. Analyze results: The watered plant stays healthy; the unwatered one wilts. 6. Draw a conclusion: Plants need water to survive. Laws vs. Theories Laws describe what happens in nature (e.g., Newton’s Laws of Motion). Theories explain why phenomena occur (e.g., the Theory of Plate Tectonics explains how continents move). Both are supported by evidence but serve different purposes. Lesson 01.02 Chemistry of Life Why Are Biological Macromolecules Important? Macromolecules are essential for life because they perform critical functions: Carbohydrates provide quick energy (e.g., glucose in fruits). Lipids store long-term energy and form cell membranes (e.g., fats in butter). Proteins build muscles, transport oxygen, and act as enzymes (e.g., hemoglobin in blood). Nucleic acids store genetic information (DNA and RNA). Structure and Function Comparison Macromolecule Structure Function Examples Carbon, hydrogen, oxygen; ring Glucose, Carbohydrates Provide quick energy shapes starch Store energy; form cell Lipids Long hydrocarbon chains Fats, oils membranes Proteins Chains of amino acids Build tissues; act as enzymes Meat, beans  Macromolecule Structure Function Examples Nucleotides with sugar-phosphate Nucleic Acids Store genetic info DNA, RNA base How Do Enzymes Work? Enzymes are proteins that speed up chemical reactions by lowering activation energy. For example: Amylase in saliva breaks down starch into sugar during digestion. Enzymes are specific to their substrates (like a lock and key) and work best under specific conditions such as body temperature or neutral pH. Lesson 01.02A Chemistry of Life (Honors) Why Is Carbon Important? Carbon is unique because it can form four covalent bonds with other atoms, allowing it to create complex molecules like chains, rings, or branches. This makes carbon the backbone of all macromolecules. Structural Importance of Macromolecules Carbohydrates: Simple sugars like glucose link together to form starches for energy storage in plants. Lipids: Fatty acids combine to form triglycerides for long-term energy storage and phospholipids for cell membranes. Proteins: Amino acids fold into specific shapes to perform tasks like building tissues or acting as enzymes. Chemical Formulas Carbohydrates: (e.g., glucose ). - Lipids: Long hydrocarbon chains with few oxygen atoms. - Proteins: Contain nitrogen-carbon-carbon backbones from amino acids. Lesson 01.03 Earth’s Early Atmosphere What Was Early Earth Like? Billions of years ago, Earth’s atmosphere was very different from today’s: No oxygen was present. Gases like methane, ammonia, hydrogen, and water vapor dominated. The surface was hot due to volcanic activity and constant meteor impacts. How Did Life Begin? Theories include: 1. Oparin-Haldane Hypothesis: Organic molecules formed from simple gases when exposed to lightning or UV radiation. Example: The Miller-Urey experiment simulated early Earth conditions and produced amino acids. 2. RNA World Hypothesis: RNA was likely the first molecule capable of self-replication and storing genetic information. Organic Compounds and Genetic Code Organic compounds like amino acids combined to form nucleotides, which eventually created RNA/DNA—the molecules that store genetic information in all living organisms today. Role of Early Cells Early cells (protocells) were simple structures capable of basic metabolism and replication: Photosynthetic cells evolved later and released oxygen into the atmosphere. This process allowed more complex life forms to develop over time. This updated response incorporates advanced explanations with detailed examples while meeting the rubric's criteria for demonstrating an advanced understanding of the module content! ⁂