Chapter 3 - Chapter 5 Organic Molecules

Hydrocarbons

Organic compounds consisting entirely of hydrogen and carbon.

Lipid

A group of organic compounds that are insoluble in water but soluble in organic solvents, including fats, oils, and waxes.

Fats

Esters of glycerol and fatty acids, serving as a major energy reserve in organisms.

Fatty acid

A carboxylic acid with a long hydrocarbon chain, which can be saturated or unsaturated.

Ester linkage

A bond formed between a fatty acid and glycerol in lipids, resulting in the release of water.

Saturated fat

A type of fat that has no double bonds between carbon atoms, typically solid at room temperature.

Unsaturated fat

A type of fat that contains one or more double bonds between carbon atoms, usually liquid at room temperature.

Polyunsaturated fat

A type of fat that contains multiple double bonds in its fatty acid chains.

Waxes

Lipids that are esters of long-chain fatty acids and long-chain alcohols, often used for waterproofing.

Oils

Liquid lipids at room temperature, primarily composed of unsaturated fatty acids.

Steroid

A type of lipid characterized by a carbon skeleton with four fused rings, important in cell signaling.

Phospholipid

A lipid molecule that is a major component of cell membranes, consisting of two fatty acids and a phosphate group attached to glycerol.

Amphipathic

Molecules that have both hydrophilic (water-attracting) and hydrophobic (water-repelling) parts.

Carbohydrate (sugar)

Organic compounds made of carbon, hydrogen, and oxygen, serving as energy sources and structural components.

Monosaccharides

The simplest form of carbohydrates, consisting of single sugar molecules like glucose and fructose.

Disaccharides

Carbohydrates formed from two monosaccharides linked by a glycosidic bond, such as sucrose.

Oligosaccharides

Carbohydrates composed of a small number of monosaccharide units, typically 3 to 10.

Polysaccharides

Carbohydrates that are long chains of monosaccharide units, such as starch and cellulose.

Glycosidic linkage

A type of covalent bond that connects monosaccharides to form disaccharides and polysaccharides.

Glycogen

A polysaccharide that serves as a form of energy storage in animals, primarily found in the liver and muscles.

Starch

A polysaccharide that serves as a form of energy storage in plants, composed of amylose and amylopectin.

Cellulose

A polysaccharide that forms the structural component of plant cell walls, composed of linear chains of glucose.

Chitin

A structural polysaccharide found in the exoskeletons of arthropods and the cell walls of fungi.

Peptidoglycan

A polymer that makes up the cell wall of bacteria, consisting of sugars and amino acids.

DNA

Deoxyribonucleic acid, the molecule that carries genetic information in living organisms.

RNA

Ribonucleic acid, a molecule involved in protein synthesis and gene expression.

RNA world hypothesis

The theory that RNA was the first self-replicating molecule, leading to the evolution of life.

Nucleic acid

Biomolecules, such as DNA and RNA, that store and transmit genetic information.

Nucleotide

The basic building block of nucleic acids, consisting of a sugar, a phosphate group, and a nitrogenous base.

Phosphodiester linkage (bond)

The bond that connects the sugar of one nucleotide to the phosphate group of another in a nucleic acid strand.

Nitrogenous base

A component of nucleotides in nucleic acids, which can be adenine, thymine, cytosine, guanine, or uracil.

Antiparallel

Referring to the opposite orientation of the two strands of DNA, where one strand runs 5' to 3' and the other runs 3' to 5'.

Complementary base pairing (Watson-Crick pairing)

The specific pairing of nitrogenous bases in DNA, where adenine pairs with thymine and cytosine pairs with guanine.

Ribozyme

An RNA molecule that has catalytic properties, capable of performing specific biochemical reactions.

Amino acids

Organic compounds that serve as the building blocks of proteins, containing an amino group, a carboxyl group, and a side chain.

Hydrophobic

Describing molecules that do not interact well with water, often nonpolar.

Hydrophilic

Describing molecules that interact well with water, often polar or charged.

Peptide bond

The covalent bond formed between two amino acids during protein synthesis.

Polypeptide

A chain of amino acids linked by peptide bonds, which folds into a functional protein.

Protein

Large biomolecules made up of one or more polypeptides, essential for various biological functions.

Denature

The process by which a protein loses its native structure due to factors like heat or pH changes, resulting in loss of function.

Catalyze

To increase the rate of a chemical reaction, often through the action of an enzyme.

Enzyme

A biological catalyst that accelerates chemical reactions in living organisms.