Chapters 1-4: Themes in the Study of Life, Chemical Context, Water, and Carbon Diversity

A set of vocabulary flashcards keying in on terms, definitions, and concepts presented across biology lecture chapters 1 through 4.

Descriptive Science

A form of science based on observation and inductive reasoning, where a set of observations leads to a general conclusion.

Inductive Reasoning

A type of logic that derives a general conclusion from a set of specific observations.

Hypothesis Based Science

A systematic approach to science that tests hypotheses through experimentation using deductive reasoning.

Deductive Reasoning

A type of logic that proceeds from general premises to specific results.

Pseudoscience

An area of study or claim that appears to be science or scientific, but is not.

Scientific Theory

A broad explanation that is not determined by a single experiment, but is supported by extensive evidence from many different scientific disciplines.

Homeostasis

An organism's ability to maintain internal equilibrium.

Evolution

A change in the genetic composition of a population over generations.

Matter

Anything formed by atoms bonded together, moving in scale from subatomic particles to atoms, molecules, and physical objects.

Element

A substance with a nucleus containing protons and neutrons, surrounded by $7$ known energy levels of electrons.

Compound

A molecule formed specifically by an ionic bond.

Protons ($p^+$)

Positively charged subatomic particles located in an atom's nucleus.

Neutrons ($n^0$)

Subatomic particles with a neutral charge located in an atom's nucleus.

Electrons ($e^-$)

Negatively charged subatomic particles surrounding the nucleus of an atom.

Atomic Number

The total number of protons ($p^+$) contained in an atom's nucleus.

Atomic Weight

The average weight of protons ($p^+$) and neutrons ($n^0$) amongst an element's isotopes.

Potential Energy

Energy that is stored within matter.

Electron Shells

Energy levels surrounding an atomic nucleus where electrons reside, possessing energy due to their relative proximity to the nucleus.

Valence Electrons

The electrons located in the outermost shell or energy level of an atom.

Octet Rule

The principle that an atom is most stable when its valence shell is completely full with a maximum of $8$ electrons (except $\text{H}$ and $\text{He}$, which require only $2$).

Covalent Bond

The strongest chemical bond, formed when atoms share electrons to reach stability.

Non-Polar Covalent Bond

A biologically strong covalent bond formed when electrons are shared equally between atoms.

Polar Covalent Bond

A covalent bond formed when electrons are shared unequally between atoms.

Ionic Bond

A chemical bond of medium strength formed by the mutual attraction between oppositely charged ions (cations and anions).

Cations

Positively charged ions ($+$) that have lost electrons, resulting in $p^+ > e^-$.

Anions

Negatively charged ions (-$ $) that have gained electrons, resulting in p^+ < e^-$$.

Hydrogen Bond

The weakest chemical bond, formed by the attraction between a slightly positive $\text{H}$ atom of one molecule and a slightly negative atom (typically $\text{N}$ or $\text{O}$) of another molecule.

Cohesion

The property of water molecules binding or sticking to other water molecules.

Adhesion

The property of water molecules sticking to other non-water molecules.

Surface Tension

A property where water molecules bind together at the surface to form a hard surface layer.

High Specific Heat

The amount of heat required to raise the temperature of $1\text{ g}$ of a substance's mass by $1^\text{o}\text{C}$.

High Heat of Vaporization

The quantity of heat required to convert $1\text{ g}$ of a liquid into a gas.

Evaporative Cooling

A process where water absorbs body heat and cools organisms as it evaporates from their surface.

Solute

The specific substance or object being dissolved in a solution.

Solvent

The liquid component of a solution that dissolves the solute.

Solution

A homogeneous mixture created when a solute dissolves into a solvent.

Hydrophilic

Water-loving molecules containing ionic or polar regions that allow them to dissolve in water.

Hydrophobic

Water-repelling molecules composed of non-polar covalent bonds that cannot form hydrogen bonds with water.

Acids

Substances that release $H^+$ ions into a solution, increasing hydrogen ion concentration and lowering the pH.

Bases

Substances that accept $H^+$ ions in a solution, decreasing hydrogen ion concentration and raising the pH.

pH

A measure of hydrogen ion concentration in a solution, calculated as $\text{pH} = -\text{log}[H^+]$.

Buffers

Substances that possess both acidic and basic properties, helping to maintain a constant pH level in biological systems.

Organic Chemistry

The branch of chemistry devoted to the study of carbon-containing compounds.

Hydrocarbons

Organic molecules composed exclusively of carbon ($\text{C}$) and hydrogen ($\text{H}$) atoms.

Isomers

Compounds that share the same molecular formula but have different physical structures and biological functions.

Structural Isomers

Isomers that differ in the covalent arrangement of their constituent atoms.

Geometric Isomers

Isomers that maintain identical covalent partnerships but differ in spatial position around double-bonded carbon atoms.

Enantiomers

Isomers that are non-superimposable mirror images of one another due to an asymmetrical carbon center.

Functional Groups

Specific combinations of atoms attached to a carbon skeleton that display consistent chemical properties.