General Biology: Foundations, Chemistry of Life, and Organic Molecules

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Qualitative Data: Descriptive data that characterizes but does not measure attributes, properties, or phenomena. Example: Color, texture, or behavior.
Quantitative Data: Numerical data that can be measured and quantified. Example: Length, mass, temperature.
Hypothesis: A testable statement or prediction about the natural world, often based on prior knowledge and observation.
Theory: A well-substantiated explanation of some aspect of the natural world, based on a body of evidence and repeatedly tested and confirmed.

Biology is the scientific study of life and living organisms, including their structure, function, growth, evolution, distribution, and taxonomy.
Seven Aspects of Life often include: organization, metabolism, homeostasis, growth, reproduction, response to stimuli, and adaptation/evolution.
Controls in Experiments: Controls are essential for comparison in scientific experiments. Negative controls lack the factor being tested, while positive controls contain the factor and are expected to produce a known result.
Inductive Reasoning: Drawing general conclusions from specific observations.
Deductive Reasoning: Making specific predictions based on general principles or premises.

Qualitative vs. Quantitative Data: Qualitative data describes qualities; quantitative data measures quantities.
Hypothesis vs. Theory: A hypothesis is a proposed explanation; a theory is a comprehensive, tested explanation.

Atom: The smallest unit of matter that retains the properties of an element.
Proton: Positively charged subatomic particle found in the nucleus.
Neutron: Neutral subatomic particle found in the nucleus.
Electron: Negatively charged subatomic particle found in orbitals around the nucleus.
Atomic Number: Number of protons in an atom's nucleus.
Mass Number: Sum of protons and neutrons in the nucleus.
Isotope: Atoms of the same element with different numbers of neutrons.
Valence Shell: The outermost electron shell of an atom; determines chemical reactivity.
Electronegativity: The tendency of an atom to attract electrons in a chemical bond.
Covalent Bond: A chemical bond formed by the sharing of electron pairs between atoms.
Nonpolar Covalent Bond: Electrons are shared equally between atoms.
Polar Covalent Bond: Electrons are shared unequally, creating partial charges.
Ionic Bond: A bond formed by the transfer of electrons from one atom to another, resulting in oppositely charged ions.
Hydrogen Bond: A weak bond between a hydrogen atom and an electronegative atom (e.g., oxygen, nitrogen).
Van der Waals Interactions: Weak attractions between molecules or parts of molecules due to transient local partial charges.

Atoms consist of protons, neutrons, and electrons. Protons and neutrons are located in the nucleus; electrons orbit in shells.
The atomic number identifies the element and equals the number of protons.
The mass number is the sum of protons and neutrons.
Isotopes are atoms of the same element with different numbers of neutrons, affecting atomic mass but not chemical properties.
Valence electrons are electrons in the outermost shell and are crucial for chemical bonding.

Ionic bonds form between atoms that transfer electrons, resulting in charged ions.
Covalent bonds form when atoms share electron pairs.
Polar covalent bonds create molecules with partial positive and negative charges (e.g., water).
Nonpolar covalent bonds share electrons equally (e.g., O2).
Hydrogen bonds are important in stabilizing biological molecules like DNA and proteins.
Van der Waals interactions contribute to the three-dimensional structure of molecules.

A chemical reaction involves the breaking and forming of chemical bonds, resulting in new substances.
To balance a chemical equation, ensure the number of atoms of each element is equal on both sides of the equation.

Polar Molecule: A molecule with an uneven distribution of charges.
Cohesion: Attraction between molecules of the same substance (e.g., water molecules).
Adhesion: Attraction between molecules of different substances.
Heat: Energy transferred between substances due to temperature difference.
Temperature: Measure of the average kinetic energy of particles.
Specific Heat: Amount of heat required to raise the temperature of 1 gram of a substance by 1°C.
Heat of Vaporization: Amount of energy required to convert 1 gram of a liquid to a gas.
Evaporative Cooling: Reduction in temperature resulting from the evaporation of a liquid.
Solution: Homogeneous mixture of two or more substances.
Solvent: Substance that dissolves the solute (e.g., water).
Solute: Substance dissolved in a solvent.
Hydrophilic: "Water-loving"; substances that dissolve easily in water.
Hydrophobic: "Water-fearing"; substances that do not dissolve easily in water.
Mole: SI unit for amount of substance; 1 mole = particles.
Molarity: Concentration of a solution, measured as moles of solute per liter of solution ().
Acid: Substance that increases the hydrogen ion concentration in a solution.
Base: Substance that reduces the hydrogen ion concentration in a solution.
Buffer: Substance that minimizes changes in pH by accepting or donating H+ ions.

Water is essential for life due to its unique properties: high specific heat, cohesion, adhesion, and ability to dissolve many substances.
Cohesion allows water molecules to stick together, contributing to surface tension.
Adhesion enables water to cling to other surfaces, important in processes like capillary action.
Hydrogen bonding is responsible for water's high specific heat and heat of vaporization.
Evaporative cooling helps regulate temperature in organisms and environments.

Solvent (e.g., water) dissolves solutes (e.g., salt) to form solutions.
Hydrophilic substances dissolve in water; hydrophobic substances do not.
Acids donate H+ ions; bases accept H+ ions.
pH measures hydrogen ion concentration:
Buffers stabilize pH in biological systems.

Carbon skeletons vary in length, branching, and ring structure, contributing to molecular diversity.
Isomers are compounds with the same molecular formula but different structures.
Types of isomers:
- Structural isomers: Differ in covalent arrangement of atoms.
- Geometric isomers: Differ in spatial arrangement around a double bond.
- Enantiomers: Mirror-image isomers, important in biological activity.

Functional Group	Structure	Properties/Function
Hydroxyl	-OH	Polar, forms hydrogen bonds, increases solubility in water
Sulfhydryl	-SH	Forms disulfide bonds, stabilizes protein structure
Methyl	-CH3	Nonpolar, affects gene expression and molecular shape
Carbonyl	-C=O	Found in aldehydes (end of chain) and ketones (within chain), increases reactivity
Carboxyl	-COOH	Acts as an acid, donates H+, found in amino acids and fatty acids
Phosphate	-PO4	Contributes negative charge, involved in energy transfer (ATP)

Recognizing functional groups is essential for understanding the chemical behavior of organic molecules.