Chapter 2 Part 2 - Organic Molecules

Vocabulary flashcards covering key concepts about organic molecules, polymers, biomolecules, and nucleic acids from Chapter 2 Part 2.

Organic molecule

Molecule that contains carbon and hydrogen and forms the basis of all organic compounds.

Hydrocarbon

A molecule composed primarily of carbon and hydrogen; serves as the backbone of many organic molecules.

Functional group

A specific group of atoms attached to a carbon skeleton that largely determines a molecule’s chemical behavior.

Hydroxyl group

The -OH group; a common functional group that makes molecules polar and influences reactivity.

Carboxyl group

The -COOH group with a carbonyl and hydroxyl; a key acidic functional group in organic acids.

Monomer

A single building block that can join with others to form polymers.

Polymer

A large molecule built from many monomers linked together.

Dehydration synthesis

A reaction that links monomers by removing water, forming a covalent bond and a polymer.

Hydrolysis

A reaction that breaks polymers by adding water, yielding monomers.

Monosaccharide

A simple sugar; the basic unit of carbohydrates; can have five or six carbon atoms.

Glucose

A six-carbon monosaccharide that provides most of the body’s immediate energy (via ATP).

Disaccharide

A carbohydrate formed by joining two monosaccharides via dehydration; examples include maltose, sucrose, and lactose.

Maltose

A disaccharide formed when two glucose units are linked.

Sucrose

Table sugar; a disaccharide formed from glucose and fructose.

Lactose

Milk sugar; a disaccharide in dairy products.

Polysaccharide

A polymer of many monosaccharides; used for energy storage or structural support.

Cellulose

Plant polysaccharide with beta linkages; forms fibers; a major component of dietary fiber and not easily digested by humans.

Lipids

A diverse group of nonpolar, hydrophobic biomolecules including fats, oils, phospholipids, and steroids.

Fatty acid tail

Long hydrocarbon chain forming the hydrophobic tail of a lipid.

Glycerol

The backbone to which fatty acids attach to form fats/oils.

Saturated fat

Fatty acids with no double bonds; straight tails; typically solid at room temperature.

Unsaturated fat

Fatty acids with one or more double bonds causing kinks; typically liquid at room temperature.

Phospholipid

A lipid with two fatty acid tails and a phosphate-containing head; essential for forming cell membranes.

Phospholipid bilayer

Two-layer arrangement of phospholipids forming the cell membrane.

Steroid

A lipid with four fused rings; includes hormones like testosterone and estrogen.

Cholesterol

A steroid essential for membrane stability and a precursor to other steroids.

Protein

A biomolecule made of amino acids that performs a wide range of cellular functions.

Amino acid

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

Peptide bond

Covalent bond joining amino acids during dehydration synthesis.

Dipeptide

Two amino acids linked by a peptide bond.

Polypeptide

A chain of many amino acids; can become a functional protein after proper folding.

Primary structure

Linear sequence of amino acids in a polypeptide.

Secondary structure

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

Tertiary structure

Three-dimensional folding of a single polypeptide, driven by side-chain interactions.

Quaternary structure

Arrangement of multiple folded polypeptides into a functional protein.

Denaturation

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

Nucleic acid

Biomolecule (DNA or RNA) composed of nucleotides that stores and transmits genetic information.

DNA

Deoxyribonucleic acid; double-stranded, uses deoxyribose, bases A, T, C, G, and forms a double helix.

RNA

Ribonucleic acid; typically single-stranded, uses ribose, bases A, U, C, G, and functions in transcription and translation.

ATP

Adenosine triphosphate; a nucleotide that stores and transfers energy via phosphate bonds.