Organic Molecules: Functional Groups and Macromolecules

Vocabulary-style flashcards covering functional groups, macromolecules, their monomers, polymers, and key examples mentioned in the notes.

Hydroxyl group

OH group; found in sugars and alcohols (often written as -OH).

Methyl group

CH3 group; found in fats, steroids, and amino acids; commonly shown in structural shorthand.

Carboxyl group

COOH group; important in amino acids and proteins; also found in some sugars; acts as an acid.

Amino group

NH2 group; part of amino acids; enables formation of proteins.

Phosphate group

PO4 group; important in nucleic acids and ATP; contributes to energy transfer and backbone chemistry.

Macromolecule

Large organic molecule with high molecular weight; examples include carbohydrates, lipids, proteins, and nucleic acids.

Polymer

Large molecule made up of many repeating monomer units.

Monomer

One repeating unit; building block of polymers; can be identical or different.

Dehydration synthesis

Chemical reaction that joins monomers by removing water; forms covalent bonds.

Hydrolysis

Chemical reaction that breaks bonds by adding water; splits polymers into monomers.

Monosaccharide

Single sugar unit; building block of carbohydrates; examples include glucose, galactose, and fructose.

Glucose

A hexose monosaccharide (C6H12O6); primary energy source in metabolism.

Galactose

Monosaccharide isomer of glucose; one of the simple sugars.

Fructose

Monosaccharide isomer of glucose; fruit sugar.

Disaccharide

Two monosaccharides covalently bonded; can be hydrolyzed into two monosaccharides; examples include sucrose, lactose, maltose.

Sucrose

Disaccharide composed of glucose and fructose; common table sugar.

Lactose

Disaccharide composed of glucose and galactose; milk sugar.

Maltose

Disaccharide composed of two glucose units.

Oligosaccharide

Three or more monosaccharides linked together; can be hydrolyzed.

Glycogen

Polysaccharide; storage form of glucose in liver, muscle, brain, uterus, and vagina.

Starch

Polysaccharide stored by plants; digestible carbohydrate.

Cellulose

Polysaccharide in plants; indigestible by humans; dietary fiber.

Carbohydrate (class)

Organic molecules with formula (CH2O)n; main energy source; monomer is monosaccharide; includes starch, glycogen, cellulose.

Glycolipid

Carbohydrate bound to lipid in a conjugated carbohydrate–lipid molecule.

Glycoprotein

Carbohydrate bound to protein in a conjugated molecule.

Proteoglycan

Macromolecule with a carbohydrate-rich component; contributes to tissue structure; moieties describe parts of the molecule.

Moiety

A part or portion of a larger molecule; a component of a conjugated macromolecule.

Lipid

Hydrophobic organic molecules; high hydrogen content; energy-dense; includes fatty acids, triglycerides, phospholipids, eicosanoids, and steroids.

Fatty acids

Hydrocarbon chain with a carboxyl end (4–24 carbons); can be saturated (no double bonds) or unsaturated (one or more double bonds).

Triglyceride

Three fatty acids attached to glycerol; primary energy storage; formed by dehydration synthesis; neutral fats.

Phospholipid

Modified triglyceride with two fatty acids and a phosphate group; amphipathic; forms cell membranes.

Eicosanoids

20-carbon fatty acid derivatives from arachidonic acid; include prostaglandins; involved in inflammation and signaling.

Prostaglandins

A type of eicosanoid; mediators of inflammation, clotting, labor, and vascular function.

Steroids

Lipids with four fused carbon rings; cholesterol is the parent steroid; include cortisol, estrogens, testosterone, bile acids.

Cholesterol

Steroid important for cell membranes; precursor to other steroids; mostly synthesized in the liver; HDL/LDL reflect transport in blood.

HDL (high-density lipoprotein)

“Good” cholesterol; lower lipid-to-protein ratio; helps remove cholesterol from tissues.

LDL (low-density lipoprotein)

“Bad” cholesterol; higher lipid-to-protein ratio; carries cholesterol in blood.

Amino acid

Monomer of proteins; contains amino group, carboxyl group, and variable R-group; linked by peptide bonds to form proteins.

Protein

Polymer of amino acids; performs structural, enzymatic, transport, and signaling roles in cells.

Nucleic acids

Polymers of nucleotides; store and transmit genetic information (DNA and RNA); contain a sugar (ribose or deoxyribose), phosphate backbone, and bases.

Nucleotide

Monomer of nucleic acids; consists of sugar, phosphate, and a nitrogenous base.