Chemistry - Organic Molecules

Vocabulary flashcards covering key terms from the Organic Molecules lecture notes.

Monomer

A small, simple molecule that can join with others to form polymers.

Polymer

A large molecule built from repeating monomer units linked by covalent bonds.

Dehydration synthesis (condensation) reaction

A reaction that links monomers by removing a water molecule.

Hydrolysis

A reaction that breaks polymers into monomers by adding water.

Carbohydrates

Organic molecules for quick energy and storage; monomer: monosaccharide; polymer: polysaccharide.

Monosaccharide

Simple sugar; monomer of carbohydrates.

Hexose sugar

A six-carbon monosaccharide (e.g., C6H12O6).

Pentose sugar

A five-carbon monosaccharide.

Disaccharide

Two monosaccharides joined together; formed by dehydration synthesis.

Polysaccharide

Polymer of many monosaccharides; examples include starch, glycogen, cellulose.

Starch

Polysaccharide with few branches used by plants for energy storage.

Glycogen

Highly branched polysaccharide for animal energy storage.

Cellulose

Structural, unbranched polysaccharide in plant cell walls; indigestible by humans.

Lipids

Macromolecule group with high energy content; fats, oils, phospholipids, steroids; generally hydrophobic.

Triglyceride

Glycerol bound to three fatty acids; main fat storage form.

Fatty acid

Hydrocarbon chain with a carboxyl group (COOH).

Saturated fatty acid

No double bonds in the hydrocarbon chain; usually solid at room temperature.

Unsaturated fatty acid

Contains one or more double bonds; can be cis or trans.

Cis

Hydrogen atoms on the same side of a double bond; causes a kink.

Trans

Hydrogen atoms on opposite sides of a double bond; typically straighter and less healthy.

Phospholipid

Glycerol + two fatty acids + phosphate; hydrophilic head and hydrophobic tail; forms cell membranes.

Steroid

Lipids with fused ring structure; include cholesterol and sex hormones such as testosterone and estrogen.

Proteins

Macromolecules with diverse roles (structure, enzymes, hormones, transport); monomer: amino acids; polymer: polypeptides.

Amino acid

Monomer of proteins; contains amino group, carboxyl group, and varying R group.

Peptide bond

Bond formed between amino acids via dehydration synthesis.

Dipeptide

Two amino acids linked by a single peptide bond.

Polypeptide

Long chain of amino acids forming a protein.

Primary structure

Linear sequence of amino acids in a polypeptide.

Secondary structure

Alpha helix or beta pleated sheet formed by hydrogen bonds.

Alpha helix

Coiled structure stabilized by hydrogen bonds.

Beta pleated sheet

Sheet-like structure stabilized by hydrogen bonds.

Tertiary structure

Three-dimensional folding of a polypeptide caused by R-group interactions; includes disulfide bonds.

Quaternary structure

Assembly of multiple polypeptide chains into a functional protein.

Denaturation

Loss of protein structure and function due to heat, pH, or other factors.

Prions

Infectious misfolded proteins that can induce misfolding in others; linked to TSE diseases.

Nucleic acids

DNA and RNA; polymers that store/express genetic information; ATP is a nucleotide energy currency.

Nucleotide

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

DNA

Deoxyribonucleic acid; stores genetic information; double-stranded; sugar is deoxyribose; bases A, T, G, C.

RNA

Ribonucleic acid; transient messenger for DNA; single-stranded; sugar is ribose; bases A, U, G, C.

Purine

Bases with two rings: Adenine and Guanine.

Pyrimidine

Bases with one ring: Cytosine, Thymine (DNA), Uracil (RNA).

Base pairing

A pairs with T (DNA) or U (RNA); G pairs with C via hydrogen bonds.

Double helix

Two antiparallel DNA strands wound into a helix.

ATP

Adenosine triphosphate; energy currency of the cell; hydrolysis releases energy.

Emulsification

Process by which polar and nonpolar ends of molecules disperse fats in water; aids digestion and detergents.

Phosphate group

Polar group in nucleotides and phospholipids; contributes to hydrophilicity.