Biology Chapter 1: The Science of Biology

Study Notes

Chapter 1: The Science of Biology

Biology integrates chemistry, physics, and mathematics.
Key characteristics of life include: cellular organization, ordered complexity, sensitivity, growth/development/reproduction, energy utilization, homeostasis, and evolutionary adaptation.
Hierarchical organization of life ranges from cellular to biosphere levels.
Emergent properties develop at each level, not predictable from lower ones.
Science uses observation and reasoning.
Deductive reasoning proceeds from general to specific, while inductive reasoning goes from specific to general.
Hypothesis-driven science involves testable explanations (hypotheses).
A good hypothesis is testable, falsifiable, allows for predictions, and is refined with data.
Experiments isolate and test variables.
Scientific theories explain natural phenomena, supported by evidence.
Charles Darwin observed variations among species on the HMS Beagle.
He developed natural selection, a mechanism for evolution.
Natural selection favors traits enhancing survival/reproduction, influenced by limited resources (Malthus).
Evidence for evolution includes the fossil record (transitional forms), comparative anatomy (homologous/analogous structures), and molecular evidence (DNA/protein similarities).
Life adheres to physical and chemical laws.
Structure dictates function in biological systems.
Living systems transform energy and matter.
Living systems rely on information transactions, like genetic code (DNA).
Evolution explains the unity and diversity of life.

Chapter 2: The Nature of Molecules and the Properties of Water

Matter is composed of atoms.
Atom structure includes protons, neutrons, and electrons.
Atomic number identifies an element.
Atomic mass is the sum of protons and neutrons.
Ions are atoms with unequal numbers of protons and electrons (cations/anions).
Living systems primarily use Carbon (C), Hydrogen (H), Oxygen (O), and Nitrogen (N).
Trace elements are crucial in small amounts.
Chemical bonds hold atoms together to form molecules.
Ionic bonds occur due to opposite charges.
Covalent bonds involve electron sharing (polar/nonpolar).
Hydrogen bonds involve partial charges.
Water is a polar molecule due to unequal electron sharing.
Hydrogen bonds between water molecules give it unique properties.
Water has a high specific heat, high heat of vaporization, and ice floats due to lower density than liquid water.
Water is a solvent for polar substances.
Nonpolar molecules cluster in water.
Water dissociates into H⁺ and OH⁻ ions.
Acids increase H⁺ concentration, raising acidity.
Bases decrease H⁺ concentration (increasing pH).
Buffers resist pH change by taking up or releasing H⁺ ions.

Chapter 3: The Chemical Building Blocks of Life

Carbon forms 4 covalent bonds, creating diverse structures in biological molecules.
Hydrocarbons are composed only of carbon and hydrogen, and are hydrophobic.
Functional groups influence molecule behavior and reactivity.
Carbohydrates store energy and provide structure.
Monosaccharides are simple sugars.
Disaccharides are two monosaccharides joined.
Polysaccharides are long carbohydrate chains (starch, glycogen, cellulose, chitin).
Nucleic acids store and transmit genetic information.
DNA is double-stranded and stores genetic instructions.
RNA is single-stranded and plays a role in protein synthesis.
RNA and DNA are composed of nucleotides (sugar, phosphate, base).
ATP is the primary energy currency in cells.
Proteins are polymers of amino acids.
Amino acids contain an amino group, carboxyl group, hydrogen, and a variable R group.
Proteins exhibit levels of structure (primary, secondary, tertiary, quaternary).
Proteins have diverse functions (catalysis, defense, transport, etc.).
Denaturation is the loss of protein structure due to environmental factors.
Lipids are hydrophobic molecules (fats, oils, phospholipids, steroids, waxes).
Fats are composed of glycerol and fatty acids (saturated/unsaturated).
Phospholipids form cell membranes through a bilayer structure.
Steroids have four fused carbon rings (cholesterol, hormones).
Dehydration synthesis builds polymers, bonding monomers by removing water.
Hydrolysis breaks down polymers by adding water.

Description

Explore the fundamental concepts of biology in this quiz, including the integration of chemistry, physics, and mathematics. Delve into the characteristics of life, the hierarchical organization, and the scientific methods used to formulate and test hypotheses. This chapter sets the stage for understanding the science that explains natural phenomena.