Polymers and Biopolymers: Polymers, DNA, and Proteins

A curated set of vocabulary flashcards covering polymers, condensation and addition polymerization, biopolymers, and protein/DNA structure to prepare for exams.

Ethene (Ethylene)

The two-carbon alkene (C2H4) that serves as the monomer for polyethylene; its double bond opens during polymerization to form long carbon–carbon chains.

Addition polymerization

A polymerization mechanism in which monomers with carbon–carbon double bonds open and add to a growing chain, forming polymers like polyethylene.

Polyethylene family

Polymers based on ethylene where the core repeating unit is two carbons; properties are tuned by branching and side groups.

Core repeating unit (polyethylene)

Two-carbon unit (–CH2–CH2–) that repeats along the polymer backbone after the double bond opens.

Homopolymer

A polymer made from a single type of monomer.

Copolymer

A polymer made from two or more different monomers.

Isotactic

A configuration where all side chains on the polymer backbone are on the same side, often giving higher density and strength.

Syndiotactic

A configuration where side chains alternate sides along the backbone.

Atactic

A configuration where side chains are arranged randomly along the backbone.

Thermoplastic

A polymer that softens or melts when heated and can be reshaped without crosslinking.

Thermoset

A crosslinked polymer that does not melt or deform upon heating.

HDPE (High-Density Polyethylene)

Polyethylene with little branching, leading to high density and strong, stiff material.

LDPE (Low-Density Polyethylene)

Polyethylene with more branching, resulting in lower density and more flexible material.

PVC (Polyvinyl chloride)

Polymer made from vinyl chloride monomer; widely used in pipes and plastics.

Teflon (PTFE)

Polytetrafluoroethylene; a highly heat-resistant, nonstick polymer used in cookware coatings and other applications.

Polystyrene

Polymer made from styrene; known for applications like Styrofoam.

Dehydration (condensation) polymerization

Reaction where water is eliminated as monomers join to form a polymer, creating ester or amide linkages in many polymers.

Diol

A molecule with two hydroxyl (–OH) groups; example in polyester and nylon formation.

Diacid

A molecule with two carboxyl (–COOH) groups; participates with diols or diamines in condensation polymers.

Ester linkage

Bond formed between a carbonyl carbon and an oxygen in polyesters after condensation (–COO–).

Polyester

A polymer formed from diol and diacid via dehydration, containing ester linkages.

Nylon (polyamide)

A polymer formed from a diol (or diamine) and a diamine (or diacid); common nylons include nylon with various monomer counts, e.g., nylon 6,6.

Dehydration reaction

Removal of water as monomers join to form polymers; central to biological and synthetic polymer formation.

Sucrose

Disaccharide formed from glucose and fructose via dehydration; common table sugar.

Amylose

Linear polymer of α-glucose in starch; digestible by humans and used for energy storage in plants.

Starch

Polymer of α-glucose (amylose and amylopectin) used for energy storage in plants; digestible by humans.

Cellulose

Polymer of β-glucose; structural carbohydrate in plants; not digestible by humans.

Alpha glucose

Isomer of glucose that forms starch (amylose) when polymerized; cyclizes into a ring in solution.

Beta glucose

Isomer of glucose that forms cellulose when polymerized; cyclizes into a ring in solution.

Glucose cyclization (α/β forms)

In water, glucose can cyclize to form two ring forms: alpha and beta, differing by the orientation of the ring hydroxyl group.

DNA backbone

Sugar–phosphate backbone formed by linking deoxyribose sugars and phosphate groups; bases attach to sugars.

Base pairing (DNA)

A pairs with T and C pairs with G through hydrogen bonding, forming the DNA double helix.

Deoxyribose vs. ribose

Deoxyribose is the sugar in DNA; ribose is the sugar in RNA; both are five‑carbon sugars ending in -ose.

Nucleotide

A building block of DNA/RNA consisting of a sugar (deoxyribose or ribose), a phosphate, and a nitrogenous base.

Amino acid

Building blocks of proteins; each contains an amino group, a carboxyl group, and a unique side chain (R).

Peptide bond

Covalent amide bond formed between amino acids by dehydration, linking them into a polypeptide chain.

Primary structure

Linear sequence of amino acids in a protein.

Secondary structure

Local folding patterns such as alpha helices and beta sheets held together by hydrogen bonds.

Tertiary structure

Three-dimensional folding of a single polypeptide, stabilized by hydrophobic, polar, ionic, and covalent interactions.

Denaturation

Unfolding of a protein’s native structure due to heat or chemical treatment, often destroying function.