The Structure and Function of Macromolecules: Carbohydrates, Lipids & Phospholipids

Vocabulary flashcards generated from the lecture transcript covering the structure and function of biological macromolecules, focusing on carbohydrates and lipids.

Macromolecules

Large biological molecules composed of thousands of covalently bonded atoms.

Polymer

A long molecule consisting of many similar building blocks called monomers.

Monomers

Small building-block molecules that serve as the subunits of polymers.

Dehydration reaction

A chemical reaction in which two monomers bond together through the loss of a water molecule.

Hydrolysis

A chemical reaction that disassembles polymers into monomers by adding a water molecule.

Monosaccharides

The simplest carbohydrates, or single sugars, which usually have molecular formulas that are multiples of $CH_2O$.

Glucose

The most common monosaccharide, having the molecular formula $C_6H_{12}O_6$.

Disaccharide

A double sugar formed when a dehydration reaction joins two monosaccharides.

Glycosidic linkage

A covalent bond formed between two monosaccharides by a dehydration reaction.

Polysaccharides

Carbohydrate polymers composed of many sugar building blocks that function in storage and structure.

Starch

A storage polysaccharide in plants consisting entirely of glucose monomers, stored as granules within chloroplasts and other plastids.

Amylose

The simplest form of starch.

Glycogen

A storage polysaccharide in animals, stored mainly in liver and muscle cells.

Cellulose

A structural polysaccharide composed of glucose monomers with beta ($\beta$) glycosidic linkages that forms tough plant cell walls.

Chitin

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

Lipids

A diverse class of large biological molecules consisting mostly of hydrocarbons that do not form polymers and are hydrophobic.

Glycerol

A three-carbon alcohol with a hydroxyl group attached to each carbon, forming part of a fat molecule.

Fatty acid

A molecule consisting of a carboxyl group attached to a long carbon skeleton.

Ester linkage

The bond joining the carbon of a fatty acid carboxyl group to the oxygen of a glycerol hydroxyl group.

Triacylglycerol

A lipid created by joining three fatty acids to a single glycerol molecule via ester linkages; also called a triglyceride.

Saturated fatty acids

Fatty acids that have no double bonds in their hydrocarbon chains and hold the maximum number of hydrogen atoms possible.

Unsaturated fatty acids

Fatty acids that have one or more double bonds in their hydrocarbon chains.

Hydrogenation

The process of converting unsaturated fats to saturated fats by adding hydrogen.

Trans fats

Unsaturated fats with trans double bonds created during the hydrogenation of vegetable oils.

Essential fatty acids

Unsaturated fatty acids required for normal growth that cannot be synthesized in the human body, such as omega-3 fatty acids.

Adipose cells

Specialized cells in humans and other mammals that store fat for energy storage, organ cushioning, and insulation.

Phospholipids

Lipids made of a hydrophilic head and two hydrophobic tails that self-assemble into bilayers, forming the major component of cell membranes.

Steroids

Lipids characterized by a carbon skeleton composed of four fused rings.

Cholesterol

An important steroid component of animal cell membranes that serves as a precursor for other steroids.