Macromolecules: Carbohydrates, Lipids, Proteins, and Nucleic Acids

Vocabulary practice flashcards covering macromolecule types, chemical reactions, lipid structures, and protein structural levels from Lecture 6.

Dehydration Synthesis

A chemical reaction that combines monomers into polymers by removing a water molecule ($H_2O$).

Hydrolysis

A chemical reaction that breaks polymers down into monomers by adding a water molecule ($H_2O$).

Monosaccharide

The simple sugar monomer subunit that links together to form carbohydrate polymers.

Starch and Glycogen

Branched complex carbohydrates used for energy storage that can be digested by humans.

Cellulose and Chitin

Straight-chain complex carbohydrates used for structural support that cannot be digested by humans.

Nucleic Acids

Biological macromolecules ($DNA$ and $RNA$) composed of nucleotide monomers that store genetic information and code for proteins.

Nucleotide

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

Glycerol

A three-carbon lipid monomer skeleton with a hydroxyl group ($\text{-OH}$) attached to each carbon.

Fatty Acid

A lipid monomer consisting of a carboxyl group ($\text{-COOH}$) attached to a long hydrocarbon chain, often $16$ to $18$ carbons long.

Triglyceride

A lipid polymer formed by binding three fatty acid chains to a glycerol molecule via dehydration synthesis, removing $3$ water molecules ($3H_2O$).

Saturated Fatty Acid

A fatty acid filled with hydrogens containing only single carbon-carbon bonds, resulting in a straight structure that is solid at room temperature.

Unsaturated Fatty Acid

A fatty acid containing one or more double carbon-carbon bonds, creating a bent structure that is liquid at room temperature.

Hydrogenation

The process of adding hydrogens to unsaturated fatty acids to remove double bonds and convert them into saturated fats.

Cis-fatty Acid

An unsaturated fatty acid with hydrogens on the same side of the double bond, causing the molecule to fold back into a U-like formation.

Trans-fatty Acid

An unsaturated fatty acid with hydrogens on opposite sides of the double bond, resulting in a linear molecule typically produced in partially hydrogenated foods.

High-Density Lipoproteins (HDL)

Known as good cholesterol; particles that pick up excess cholesterol in the body and transport it back to the liver for processing.

Low-Density Lipoproteins (LDL)

Known as bad cholesterol; particles that transport cholesterol throughout the body, where excess buildup in artery walls narrows blood flow.

Phospholipid

An amphipathic lipid consisting of a polar, hydrophilic phosphate head and two non-polar, hydrophobic fatty acid tails.

Amphipathic

Describing a dual-nature molecule that contains both hydrophobic (water-fearing) and hydrophilic (water-loving) regions.

Amino Acid

The monomer building block of proteins, consisting of a central carbon bonded to an amino group ($\text{-NH}_2$), a carboxylic acid group ($\text{-COOH}$), a hydrogen, and a variable side chain (R group).

Primary Protein Structure

The linear sequence of amino acids in a polypeptide chain linked together by strong covalent peptide bonds.

Secondary Protein Structure

Local folding patterns in a polypeptide backbone, such as alpha helices and beta pleated sheets, stabilized by hydrogen bonding.

Tertiary Protein Structure

The overall functional 3D shape of a single polypeptide chain, stabilized by hydrogen bonds, hydrophobic interactions, disulfide bridges, and ionic bonds.

Quaternary Protein Structure

The structural level formed by the aggregation of two or more individual polypeptide chains (tertiary protein subunits), such as collagen or hemoglobin.

Myoglobin

A single-chain tertiary protein found primarily in muscle tissue that serves as an intracellular storage site for oxygen.

Denaturation

The process in which extreme environmental conditions (such as temperature or pH changes) disrupt a protein's 3D shape and function without altering its primary amino acid sequence.