Unit 1 Vocabulary Flashcards

Quiz-style Q&A flashcards covering Unit 1 vocabulary terms from pages 1–4.

What is the definition of Acid?

molecule that donates hydrogen ions and increases the concentration of hydrogen ions in a solution

What is the definition of Adhesion?

attraction between water molecules and other molecules

What is the definition of Alpha Helix?

type of secondary structure of proteins formed by folding of the polypeptide into a helix shape with hydrogen bonds stabilizing the structure

What is the definition of Amine Group?

NH₂

What is the definition of Amino Acid?

monomer of a protein; has a central carbon or alpha carbon to which an amino group, a carboxyl group, a hydrogen, and an R group or side chain is attached; the R group is different for the most common 20 amino acids

What is the definition of Amphipathic?

having both hydrophilic and hydrophobic parts

What is the definition of ATP?

adenosine triphosphate, the cell’s energy currency

What is the definition of Base?

molecule that donates hydroxide ions or otherwise binds excess hydrogen ions and decreases the concentration of hydrogen ions in a solution

What is the definition of Base-Pair Rule?

set of rules that describe how nitrogenous bases pair together in DNA and RNA (adenine pairs with thymine, cytosine pairs with guanine; in RNA thymine pairs with uracil)

What is the definition of Beta Sheet?

secondary structure found in proteins in which “pleats” are formed by hydrogen bonding between atoms on the backbone of the polypeptide chain

What is the definition of Biochemistry?

study of the chemistry of biological organisms

What is the definition of Capillary Action?

occurs because water molecules are attracted to charges on the inner surfaces of narrow tubular structures such as glass tubes, drawing the water molecules to the sides of the tubes

What is the definition of Carbohydrate?

biological macromolecule in which the ratio of carbon to hydrogen and to oxygen is 1:2:1; serve as energy sources and structural support in cells

What is the definition of Carboxyl Group?

-COOH

What is the definition of Cholesterol?

a type of fate made by the body from saturated fats; a minor part of fat in foods

What is the definition of Cohesion?

intermolecular forces between water molecules cause by the polar nature of water; responsible for surface tension

What is the definition of Covalent Bond?

type of strong bond formed between two atoms of the same or different elements; forms when electrons are shared between atoms

What is the definition of Defensive Proteins?

proteins that help organisms fight infection, heal wounds, and evade predators

What is the definition of Dehydration Synthesis?

(also condensation) reaction that links monomer molecules together, releasing a molecule of water for each bond formed

What is the definition of Denaturation?

loss of shape in a protein as a result of changes in temperature, pH, or exposure to chemicals

What is the definition of Density of water?

weight of water per unit volume

What is the definition of Deoxyribose sugar?

five-carbon sugar that is a key component of DNA or deoxyribonucleic acid

What is the definition of Disaccharide?

two sugar monomers that are linked together by a glycosidic bond

What is the definition of DNA?

double-helical molecule that carries the hereditary information of the cell

What is the definition of Electronegativity?

ability of some elements to attract electrons (often of hydrogen atoms), acquiring partial negative charges in molecules and creating partial positive charges on the hydrogen atoms

What is the definition of Enzyme Proteins?

catalyze reactions

What is the definition of Fatty Acid?

carboxylic acid consisting of a hydrocarbon chain and a terminal carboxyl group

What is the definition of Glycerol?

three-carbon alcohol with a hydroxyl group attached to each carbon

What is the definition of Glycosidic Bond?

bonds formed by a dehydration reaction between two monosaccharides with the elimination of a water molecule

What is the definition of Hormonal Proteins?

provide coordination of an organism’ activities (i.e. insulin)

What is the definition of Hydrogen Bond?

weak bond between slightly positively charged hydrogen atoms and slightly negatively charged atoms in other molecules

What is the definition of Hydrolysis?

reaction that causes breakdown of larger molecules into smaller molecules with the utilization of water

What is the definition of Hydrophilic?

describes ions or polar molecules that interact well with other polar molecules such as water

What is the definition of Hydrophobic?

describes uncharged nonpolar molecules that do not interact well with polar molecules such as water

What is the definition of Hydroxyl Group?

OH⁻

What is the definition of Ion?

atom or chemical group that does not contain equal numbers of protons and electrons

What is the definition of Ionic Bond?

chemical bond that forms between ions with opposite charges (cations and anions)

What is the definition of Lipid?

macromolecule that is nonpolar and insoluble in water

What is the definition of Macromolecule?

large molecule, typically formed by the joining of smaller molecules

What is the definition of Methyl Group?

CH₃

What is the definition of Monomer?

smallest unit of larger molecules called polymers

What is the definition of Monosaccharide?

single unit or monomer of carbohydrates

What is the definition of Motor Proteins?

a protein that interacts with cytoskeletal elements and other cell components, producing movements of the cell or parts of the cell, used for movement

What is the definition of Non-Polar Molecule?

molecule where the electrical charge is evenly distributed across its structure, meaning there are no distinct positive or negative poles, and the molecule has no separation of charge due to its symmetrical arrangement of atoms with similar electronegativity

What is the definition of Nucleic Acid?

biological macromolecule that carries the genetic blueprint of a cell and carries instructions for the functioning of the cell

What is the definition of Nucleotide?

monomer of nucleic acids; contains a pentose sugar, one or more phosphate groups, and a nitrogenous base

What is the definition of Organic Molecule?

any molecule containing carbon (except carbon dioxide)

What is the definition of Peptide Bond?

bond formed between two amino acids by a dehydration reaction

What is the definition of pH?

a measurement of how acidic or basic a solution is; indicates the concentration of hydrogen ions (h+) in a substance

What is the definition of Phosphate Group?

PO₄

What is the definition of Phospholipid?

major constituent of the membranes; composed of two fatty acids and a phosphate-containing group attached to a glycerol backbone

What is the definition of Polar Molecule?

molecule where the electrons are distributed unevenly, creating distinct regions of positive and negative charge

What is the definition of Polymer?

chain of monomer residues that is linked by covalent bonds; polymerization is the process of polymer formation from monomers by condensation

What is the definition of Polypeptide?

long chain of amino acids linked by peptide bonds

What is the definition of Polysaccharide?

long chain of monosaccharides may be branched or unbranched

What is the definition of Primary Structure?

linear sequence of amino acids in a protein

What is the definition of Protein?

biological macromolecule composed of one or more chains of amino acids

What is the definition of Proton (H+)?

positively charged particle that resides in the nucleus of an atom; has a mass of one amu and a charge of +1

What is the definition of Purines?

type of nitrogenous base in DNA and RNA; adenine and guanine are purines

What is the definition of Pyrimidines?

type of nitrogenous base in DNA and RNA; cytosine, thymine, and uracil are pyrimidines

What is the definition of Quaternary Structure?

association of discrete polypeptide subunits in a protein

What is the definition of R-Group?

a functional group that defines a particular amino acid and gives it special properties

What is the definition of Receptor Proteins?

a protein that interacts with cytoskeletal elements and other cell components, producing movement of the whole cell or parts of the cell, used in communication and cell signaling

What is the definition of Ribose Sugar?

sugar used in RNA to make up the “backbone”

What is the definition of RNA?

single-stranded, often internally base paired, molecule that is involved in protein synthesis

What is the definition of Saturated Fat?

long chain of hydrocarbon with single covalent bonds in the carbon chain; the number of hydrogen atoms attached to the carbon skeleton is maximized

What is the definition of Solute?

substance dissolved in a liquid to form a solution

What is the definition of Solution?

a homogeneous mixture of two or more substances

What is the definition of Solvent?

substance capable of dissolving another substance

What is the definition of Specific Heat Capacity?

the amount of heat one gram of a substance must absorb or lose to change its temperature by one degree Celsius

What is the definition of Storage Proteins?

store amino acids for later use

What is the definition of Structural Proteins?

provide physical stability and movement

What is the definition of Surface Tension?

tension at the surface of a body of liquid that prevents the molecules from separating; created by the cohesive forces between the molecules of the liquid

What is the definition of Tertiary Structure?

three-dimensional conformation of a protein, including interactions between secondary structural elements; formed from interactions between amino acid side chains

What is the definition of Transport Proteins?

membrane protein that facilitates passage of a substance across a membrane by binding it

What is the definition of Triglyceride?

fat molecule; consists of three fatty acids linked to a glycerol molecule

What is the definition of Unsaturated Fat?

long-chain hydrocarbon that has one or more double bonds in the hydrocarbon chain

What is the definition of Water-universal solvent?

Water is the universal solvent