AP Bio Key term Chapter 5

Macromolecule

giant, complex molecules essential for life

Monomer

a small, basic molecule that acts as the fundamental building block

Polymer

a large molecule made by chaining together many smaller, identical or similar building blocks called monomers

Polymerization

a chemical process where small, basic molecules (called monomers) link together to form long, chain-like structures (called polymers).

Dehydration synthesis

a chemical reaction where smaller molecules, called monomers, bond together to form a larger molecule, known as a polymer

Hydrolysis

common chemical reaction where water (\(H_{2}O\)) is used to break the chemical bonds within a larger molecule

Enzyme

specialized proteins that act as biological catalysts

Carbohydrate

made of only one or two sugar molecules, allowing them to be digested and absorbed very quickly

Monosaccharide

the most basic unit of carbohydrates, commonly known as a "simple sugar"

Disaccharide

a "double sugar" made by joining two single sugars together

Polysaccharide

a complex carbohydrate made of long chains of simple sugar molecules (monosaccharides) linked together

Glycosidic bond

a strong covalent bond that joins a sugar (carbohydrate) molecule to another group

Starch

the specific type of chemical connection that links individual sugar molecules (glucose) together to form a large, complex starch molecule

Glycogen

the chemical connection that binds individual glucose sugar molecules together to form glycogen

Cellulose

the chemical link that holds individual sugar (glucose) molecules together into long, rigid chains to form cellulose

Chitin

a tough, natural sugar-based carbohydrate that acts as nature's building material

Lipid

a diverse group of organic compounds that are insoluble in water but dissolve in organic solvents

Fatty acid

the basic building blocks of fats and oils

Saturated fatty acid

a type of fat molecule where the carbon chain is completely "saturated" with hydrogen atoms

Unsaturated fatty acid

a type of fat containing one or more "kinks" or double bonds in its chemical structure, which means it is not completely packed with hydrogen atoms

Triglyceride

the most common type of fat in your body

Phospholipid

a type of lipid molecule that is the primary building block of cell membranes

Steroid

defined by a specific chemical structure of four fused carbon rings. Steroids act as essential structural components of cell membranes (like cholesterol)

Cholesterol

a waxy, fat-like substance that is essential for human life

Amphipathic

a molecule that has both a water-loving (hydrophilic) part and a water-fearing (hydrophobic) part

Lipid bilayer

a double-layered barrier that surrounds all cells.

Nucleic acid

large biological molecules that store and transmit genetic information

Nucleotide

the fundamental building blocks of DNA and RNA

Deoxyribose

a simple, five-carbon sugar that serves as a core building block of DNA (Uses thymine)

Ribose

a naturally occurring simple sugar containing five carbon atoms (Uses uracil)

Nitrogenous base

the essential, nitrogen-containing building blocks of DNA and RNA

Antiparallel

two strands that run parallel to each other, but point in opposite directions

Double helix

the term used to describe the physical structure of DNA.

Phosphodiester bond

the strong covalent link that joins individual nucleotides together to form the backbone of DNA and RNA

3’ end

(pronounced "three-prime end"); tail end of a DNA or RNA strand that has a free hydroxyl (-OH) group attached to the third carbon of the sugar ring. It is the "active" end where new building blocks (nucleotides)

5’ end

the start of a DNA or RNA strand

Amino acid

organic compounds that serve as the building blocks of proteins

R group (side chain)

the unique, variable part of an amino acid that dictates its chemical behavior.

Peptide bond

a strong covalent chemical bond that links amino acids together to form proteins.

Peptide bond

the exact sequence of amino acids in a polypeptide chain

Polypeptide

a long, continuous chain of amino acids linked together by chemical bonds called peptide bonds.

Primary structure

its exact, linear sequence of amino acids.

Secondary structure

the localized, repeating 3D shapes formed by the backbone of a biological molecule

Tertiary structure

the overall three-dimensional shape of a single protein molecule

Quaternary structure

the highest level of protein organization in biology.

a-helix

a common, ribbon-like shape found in proteins

B-pleated sheet

a common folded shape in proteins (a "secondary structure")

Disulfide bridge

a strong, permanent chemical bond between the sulfur atoms of two cysteine amino acids in a protein

Hydrophobic interaction

the natural tendency of "water-fearing" (nonpolar) molecules to clump together and hide from water

Ionic interaction

an electrostatic attraction between a positively charged atom or molecule and a negatively charged one