Biology Exam 1 Study Guide Flashcards

Vocabulary practice flashcards covering core concepts in introductory biology and chemistry, including levels of organization, scientific methods, taxonomic classification, subatomic structure, chemical bonding, and biological macromolecules.

Cell

The smallest unit of life that can exist as a separate entity.

Community

An ecological level of organization that includes all populations of all species in a given area.

Ecosystem

An ecological level of organization where living organisms interact with physical and chemical environment factors such as sunlight, rainfall, and temperature.

Photosynthesis

The chemical process that converts solar energy into chemical energy.

Homeostasis

The state in which a cell or organism maintains a relatively constant internal environment within a limited range of variation.

Scientific Name

A formal two-part biological designation consisting of a genus name followed by a species name.

Genera

The plural form of the word genus.

Domain

The most inclusive biological taxonomic category that encompasses all other classification groups.

Protista

A taxonomic group consisting of eukaryotic, single-celled organisms of considerable internal complexity.

Archaea

A domain of prokaryotic organisms that is evolutionarily closest to eukaryotes.

Plantae

A taxonomic kingdom of multicellular photosynthetic producers.

Fungi

A taxonomic kingdom composed of multicellular decomposers.

Bacteria

Single-celled prokaryotic organisms that lack membrane-bound nuclei and are not eukaryotes.

Mutation

A molecular change in the hereditary instructions (DNA) of an organism.

Population

A group of individuals of the same species occupying a specified area; the level of biological organization at which evolution occurs.

Hypothesis

A testable prediction or tentative explanation offered for an observed problem or phenomenon.

Experiment

A systematic test or procedure conducted by scientists to test a hypothesis and arrive at a solution.

Control Group

In an experiment, a subject group treated identically to the experimental group except for one variable, providing a standard of comparison.

Atom

The smallest unit of an element that retains all the specific properties of that element.

Proton

A positively charged subatomic particle located in the nucleus of an atom.

Neutron

An uncharged (neutral) subatomic particle located in the nucleus of an atom.

Electron

A negatively charged subatomic particle that occupies orbitals surrounding the atomic nucleus.

Atomic Number

The total number of protons found in the nucleus of an atom.

Atomic Mass

The value determined by the combined masses of an atom's protons and neutrons.

Demitri Mendeleev

The scientist who devised the periodic table of the elements.

Radioactive Isotope

An unstable form of an element characterized by having excess neutrons in its nucleus.

Ion

An atom or molecule that has gained or lost one or more electrons, acquiring an electrical charge.

Compound

A chemical combination of two or more different elements in fixed proportions.

Ionic Bond

A chemical bond formed by the attraction between oppositely charged ions, such as in table salt ($\text{NaCl}$).

Nonpolar Covalent Bond

A covalent bond in which both participating atoms exert an equal pull on shared electrons.

Hydrogen Bond

An attractive force between a hydrogen atom and either an oxygen or nitrogen atom located in another molecule or within the same molecule.

Hydrophobic Molecules

Nonpolar molecules that are repelled by water.

Hydroxyl Group ($\text{--OH}$)

A functional group consisting of an oxygen atom bonded to a hydrogen atom, occurring repeatedly in sugars.

Methyl Group ($\text{--CH}_3$)

A nonpolar functional group consisting of one carbon atom covalently bonded to three hydrogen atoms.

Amino Group ($\text{--NH}_2$)

An amine functional group located at the amino-terminal end of proteins.

Carboxyl Group ($\text{--COOH}$)

An acidic functional group located at the carboxyl-terminal end of proteins.

Condensation Reaction

A chemical reaction that forms larger molecules by linking smaller monomers together while releasing water molecules.

Hydrolysis Reaction

The breakdown of large molecules into smaller subunits by the enzymatic addition of water.

Sucrose

The most plentiful sugar in nature, formed by a disaccharide combination of one glucose molecule and one fructose molecule.

Starch

A storage polysaccharide used by plants to store excess carbohydrates.

Glycogen

A polysaccharide used for energy storage in animals.

Triglycerides

Neutral fat lipid molecules produced by condensation reactions linking one glycerol molecule with three fatty acid chains.

Primary Protein Structure

The linear sequence of amino acids held together by covalent peptide bonds in a polypeptide chain.

Secondary Protein Structure

Structural shapes adopted by protein chains, taking the form of twists, bends, loops, and folds.

Nucleotides

The basic building block monomers for nucleic acids and energy-carrying molecules like ATP, NAD+, and FAD.