General Biology Study Outline Chapters 1, 2, and 3

General Biology Study Outline: Chapters 1, 2, and 3

Chapter 1: Introduction to Biology and Chemistry

• Science as a Process: Science is the study of the natural world utilizing the scientific method.

• Scientific Method:

  • Observe and generalize: Initial observations about the natural world.

  • Formulate a hypothesis: A testable explanation for the observation.

  • Make a testable prediction: A statement about what will happen if the hypothesis is correct.

  • Experiment or observe: Conduct experiments or make observations to test the prediction.

  • Modify the hypothesis: Revise the hypothesis based on the experimental results; repeat the process.

  • Share with the scientific community: Communicate findings through publications and presentations.

• Key Definitions:

  • Hypothesis: A testable explanation for an observation.

  • Scientific Theory: A well-substantiated explanation of some aspect of the natural world, based on a body of facts that have been repeatedly confirmed through observation and experiment.

• Examples of Theories:

  • Cell Theory: All living organisms are composed of cells.

  • Evolution via Natural Selection: The process by which organisms change over time as a result of changes in heritable physical or behavioral traits.

• Characteristics of Living Organisms:

  • Composed of one or more cells.

  • Reproduce autonomously using DNA.

  • Obtain energy from the environment for cellular work.

  • Sense and respond to the environment.

  • Maintain a separate and fairly consistent internal environment (homeostasis).

  • Evolve, adapt, and change in response to the environment.

• Definitions:

  • Chemistry: The study of matter and its properties as well as how matter changes.

  • Matter: Anything that has mass and takes up space.

  • Elements: Substances that cannot be broken down into simpler substances by chemical means.

• Energy:

  • Energy: The capacity to do work.

  • Potential Energy: Stored energy.

  • Kinetic Energy: Energy of motion.

• Atomic Structure:

  • Atoms are composed of protons, neutrons, and electrons.

• Chemical Bonds:

  • Covalent Bond: Sharing of electrons between atoms (e.g., bond in a water molecule).

  • Ionic Bond: Transfer of electrons between atoms, resulting in ions that are attracted to each other (e.g., NaCl).

  • Hydrogen Bond: Weak attraction between a hydrogen atom with a partial positive charge and another atom with a partial negative charge (e.g., between water molecules).

• Water:

  • Polar Molecule: Unequal sharing of electrons creates partial charges.

  • Liquid at Body Temperature: Suitable medium for biological reactions.

  • High Heat Capacity: Absorbs and holds heat energy, moderating temperature.

  • Biological Solvent: Dissolves many substances necessary for life.

  • Temperature Regulation: Helps regulate body temperature due to its high heat capacity.

• Definitions:

  • Solute: A substance that is dissolved in a solvent.

  • Solvent: A substance that dissolves a solute.

  • Hydrophilic: Substances that dissolve in water ("water-loving").

  • Hydrophobic: Substances that do not dissolve in water ("water-fearing").

• pH Scale:

  • pH Scale: A measure of the acidity or alkalinity of a solution.

  • Acids: Substances with a pH less than 7.

  • Bases: Substances with a pH greater than 7.

  • Neutral pH: pH of 7 (e.g., pure water).

  • Buffers: Substances that resist changes in pH.

Chapter 2: Macromolecules

• Definitions:

  • Atoms: The basic units of matter.

  • Elements: Substances that cannot be broken down into simpler substances by chemical means.

  • Chemical Reactions: Processes that involve the rearrangement of atoms and molecules.

  • Organic Molecules: Molecules containing carbon.

• Importance of Carbon:

  • Comprises 18% of the human body by weight.

  • Forms four covalent bonds, allowing for diverse molecular structures.

  • Can form single or double bonds.

  • Can build micro- or macromolecules.

• Dehydration Synthesis and Hydrolysis:

  • Dehydration Synthesis: A chemical reaction that removes a water molecule to form a bond.

  • Hydrolysis: A chemical reaction that adds a water molecule to break a bond.

• Carbohydrates:

  • Formed from sugars.

  • Monosaccharides: Simple sugars (e.g., Glucose, Fructose, Galactose, Ribose, Deoxyribose).

  • Disaccharides: Two monosaccharides bonded together (e.g., Sucrose, Maltose, Lactose).

  • Polysaccharides: Thousands of monosaccharides joined in chains and branches (e.g., starch, glycogen, cellulose).

• Lipids:

  • Hydrophobic macromolecules.

  • Triglycerides: Glycerol and three fatty acid chains; classified as saturated and unsaturated fats.

  • Phospholipids: Glycerol, phosphate group, and two fatty acid chains; main component of plasma membranes. Head is hydrophilic, tails are hydrophobic.

  • Steroids: Four carbon rings (e.g., cholesterol, estrogen, testosterone).

• Proteins:

  • Large macromolecules composed of amino acids.

  • Amino Acids: 20 known amino acids; 8 are essential (not manufactured solely in the human body).

  • Peptide Bonds: Bonds between amino acids.

  • Three-Dimensional Structure: Determines the function of the molecule. Primary, secondary, tertiary, and quaternary structure.

  • Denaturation: Change in protein shape due to temperature or pH changes, leading to loss of function.

  • Enzymes: Proteins that catalyze chemical reactions and speed them up. Essential for life.

• Nucleic Acids:

  • Store genetic information (DNA and RNA).

  • DNA (Deoxyribonucleic Acid): Deoxyribose sugar, phosphate, and four nucleic acid bases (Adenine, Thymine, Cytosine, Guanine). Double-stranded helix with A pairing with T and C pairing with G.

  • RNA (Ribonucleic Acid): Ribose sugar, phosphate, and four nucleic acid bases (Adenine, Uracil, Cytosine, Guanine). Single-stranded.

  • DNA -> RNA -> Protein: DNAs are the instructions for making RNAs and RNAs are the instructions for making proteins.

  • ATP (Adenosine Triphosphate): Energy source for cellular life. Phosphate bonds are broken from ATP to release energy, forming ADP.

Chapter 3: Cells

• Levels of Biological Study:

  • Atoms/Molecules, Cell, Tissue, Organ, Organ Systems, Organism, Population, Community, Ecosystem, Biosphere.

• Animal Cell Components:

  • Nucleus, Smooth ER, Rough ER, Cytoskeleton, Mitochondria, Golgi Apparatus, Plasma Membrane, Ribosomes, Lysosomes, Centriole, Flagellum.

• Plant Cell Components:

  • Nucleus, Smooth ER, Rough ER, Cytoskeleton, Mitochondria, Golgi Apparatus, Plasma Membrane, Ribosomes, Chloroplast, Cell Wall, Vacuole.

• Plastids:

  • Organelles in plant cells.

    • Chloroplasts: Photosynthesis.

    • Chromoplasts: Add color to plants.

    • Leucoplasts: Storage of starch or oil.

• Advances in Genetic Research:

  • Human insulin production from bacteria with inserted human insulin gene.

• Genome Sequencing:

  • Human genome sequenced; many prokaryote genomes sequenced; dozens of eukaryote genomes sequenced each year.

• Synthetic Biology:

  • 2008: First synthetic chromosome produced.

  • 2010: First synthetic cell (Mycoplasma) produced.

• Transport Across Plasma Membrane:

  • Passive Transport: Diffusion, facilitated diffusion, and osmosis.

  • Active Transport: Requires energy to move substances against their concentration gradients.