Biology Basics: Living Things and Biomolecules

Vocabulary flashcards covering biology basics: life concepts, cells, genetics, metabolism, homeostasis, evolution, and the four biomolecules (carbohydrates, lipids, proteins, nucleic acids) plus enzymes and pH concepts.

Biology

The science that studies life and living organisms.

Bios

Life or living things.

-ology

A suffix meaning study of; used to name scientific fields.

Cell

The smallest unit of an organism that is alive.

Unicellular

Consisting of one cell.

Multicellular

Consisting of many cells.

Reproduction

Production of new organisms.

DNA

Deoxyribonucleic acid; the universal genetic code that stores genetic information.

Growth

An increase in size.

Development

Changes that occur as an organism grows.

Producers

Organisms that make their own food (autotrophs).

Consumers

Organisms that eat other living things (heterotrophs).

Respond to environment

Living things respond to stimuli such as temperature or light.

Homeostasis

Maintenance of a relatively stable internal environment.

Evolution

Change over time in a group of living things.

Macromolecules

Large molecules formed by joining smaller units (monomers) into polymers.

Monomer

A single unit that can join to form polymers.

Polymer

A large molecule made of many monomer units.

Macromolecule (general)

Large organic molecules like carbohydrates, lipids, proteins, and nucleic acids.

Carbohydrates

Macromolecules made of glucose; primary energy source; examples include glucose, starch; cellulose and chitin are structural carbohydrates.

Glucose

A monosaccharide; C6H12O6; a main energy source for cells.

Proteins

Macromolecules made of amino acids; perform many functions (enzymes, antibodies, structural components).

Amino Acids

Monomers of proteins.

Lipids

Macromolecules made of fatty acids and glycerol; store energy and form cell membranes.

Nucleic Acids

Macromolecules made of nucleotides; include DNA and RNA; store and transmit genetic information.

Nucleotide

Monomer of nucleic acids.

DNA (Deoxyribonucleic Acid)

Stores genetic information; typically double-helix structure.

RNA (Ribonucleic Acid)

Involved in protein synthesis; usually single-stranded.

Base Pair

Complementary nucleobases that form the rungs of DNA (A-T, G-C) or RNA (A-U, G-C).

Enzymes

Proteins that act as biological catalysts to speed up chemical reactions.

Active Site

The region of an enzyme where substrates bind.

Substrate

The reactants that bind to an enzyme’s active site.

Lock-and-Key Model

Model of enzyme action where substrate fits the active site like a key fits a lock.

Catalyst

A substance that speeds up a chemical reaction by lowering its activation energy; enzymes are biological catalysts.

Optimal Temperature

The temperature at which an enzyme works best; deviations can affect activity.

pH

A measure of how acidic or basic a solution is; scale 0-14; 7 is neutral.

Buffer

Weak acids or bases that resist changes in pH.

Acid

A substance that donates H+ ions; pH < 7.

Base

A substance that accepts H+ ions; pH > 7.

Lactase

Enzyme that digests lactose; deficiency can cause lactose intolerance.