Functional Groups and Macromolecules

Sulfhydryl

-SH, polar. 2 SH can react, forming a cross link

Hydroxyl

-OH, polar. Found in alcohols, tend to make substances dissolve in water.

Carbonyl

C=O, polar

Ketone

C=O in the middle

Aldehyde

C=O at the end

Carboxyl

COOH, polar. Acts like an acid (donates H+ ions and lowers PH)

Amino

NH2, acts like a base (picks up H+ ions and increases PH)

Phosphate

-OPO3^-2, Polar in 2 places, often involved in energy reactions (ATP)

Methyl

-CH3, nonpolar

Polymer

A long molecule consisting of many similar or identical monomers linked together.

Monomer

A simple compound whose molecules can join together to form polymers

dehydration synthesis

A chemical reaction in which two molecules covalently bond to each other with the removal of a water molecule.

Hydrolysis

Breaking down complex molecules by the chemical addition of water

Enzyme

A type of special macromolecule that speeds up a chemical reaction (making and breaking polymers)

Carbohydrates

Sugars and polymers of sugars

Monosaccharides

Simple sugars. Usually have multiples of CH20. serve as a major fuel for cells and as raw material for building molecules

Glucose

Most common monosaccharide. C6H12O6

Disaccharide

A double sugar, consisting of two monosaccharides joined by dehydration synthesis.

glycosidic linkage

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

Polysaccharides

Carbohydrates that are made up of more than two monosaccharides. Have storage and structural roles. Structure and function are determined by its sugar monomers and position of glycosidic linkages.

Starch

A storage polysaccharide in plants consisting entirely of glucose. Simplest form is amylose. helical structure.

Glycogen

An extensively branched glucose storage polysaccharide found in the liver and muscle of animals; the animal equivalent of starch. Hydrolysis of glycogen releases glucose when needed

Cellulose

polysaccharide consisting of glucose monomers that reinforces plant-cell walls. straight and unbranched structure

alpha and beta ring structures

Hydroxyl group attached in different position
(in alpha the hydroxyl group is attached to number 1 carbon below the plane of the ring, in beta the hydroxyl group is attached to number 1 carbon above the plane of the ring)

Chitin

A structural polysaccharide, consisting of amino sugar monomers, found in many fungal cell walls and in the exoskeletons of all arthropods.

Lipids

one class of large biological molecules that does not include true polymers. Unifying trait is that they all mix poorly with water. consist mainly of hydrocarbons

Fats

constructed from two types of smaller molecules: glycerol and fatty acids

glycerol

a three-carbon alcohol with a hydroxyl group attached to each carbon

fatty acid

carboxyl group attached to a long carbon skeleton

triaclyglycerol/triglyceride (fat)

3 fatty acids and 1 glycerol molecule
ester linkage between glycerol and each fatty acid chain (dehydration synthesis)
hydrophobic molecule

ester linkage

The linkage formed between the glycerol molecule and the fatty acids in a fat is the ester linkage. This bond is formed through dehydration synthesis.

saturated fatty acid

A fatty acid in which all carbons in the hydrocarbon tail are connected by single bonds. solid at room temp. found in animals

unsaturated fatty acid

A fatty acid possessing one or more double bonds between the carbons in the hydrocarbon tail. liquid at room temp. found in plants and fish

Hydrogenation

The process of converting unsaturated fats to saturated fats by adding hydrogen (trans fats)

Phospholipids

a lipid consisting of a glycerol bound to two fatty acids and a phosphate group. phosphate group and attatchments form a hydrophilic head, but fatty acid chains are hydrophobic.

phospholipid bilayer

A double layer of phospholipids that makes up plasma and organelle membranes. boundary between cell and external environment

Steriods

Steroids are a class of lipids that have a basic structure of four linked carbon rings and include cholesterol, vitamin D, and a variety of hormones.

Protein

a biologically functional molecule that consists of one or more polypeptides

protein functions

structural support, storage, transport, cellular communications, movement, and defense against foreign substances

Enzymes

Proteins that speed up chemical reactions

Polypeptide

A polymer (chain) of many amino acids linked together by peptide bonds. Unbranched

peptide bond

The chemical bond that forms between the carboxyl group of one amino acid and the amino group of another amino acid

4 parts of amino acids

-central carbon (alpha carbon)
-amine group *NH2
-carboxyl group *COOH
-R group (20 different groups)

• hydrogen

Gene

A unit of inheritance that programs the amino acid sequence of a polypeptide

deoxyribonucleic acid (DNA)

A double-stranded, helical nucleic acid molecule capable of replicating and determining the inherited structure of a cell's proteins. makes up genes. contains deoxyribose sugar.

ribonucleic acid (RNA)

single-stranded nucleic acid that contains the sugar ribose

Nitrogenious base of DNA

Adenine, Thymine, Cytosine, Guanine

Nitrogenous base of RNA

Adenine, Uracil, Guanine, Cytosine

Purine bases

Adenine and Guanine, double ring structure

Pyrimidine bases

cytosine, thymine, uracil, single ring structure

polynucleotide

A polymer consisting of many nucleotide monomers in a chain; nucleotides can be those of DNA or RNA. (another word for nucleic acid)

Nucleotide structure

nitrogenous base, pentose sugar, 1+ phosphate group

Nucleoside

nitrogenous base + sugar (without phosphate)

phosphodiester bond

the type of bond that links the nucleotides in DNA or RNA. joins the phosphate group of one nucleotide to the hydroxyl group on the sugar of another nucleotide

Isomers

Two different molecules that have the same chemical formula

structural isomers

same atoms, but differ in the covalent arrangements of their atoms

cis-trans isomers

carbons have covalent bonds to the same atoms, but these atoms differ in their spatial arrangements

Enantiomers

isomers that are mirror images of each other