Unit 2- Biochemisty

hydrogen bond

weak attraction between a hydrogen atom and another atom

polar molecule

molecule with an unequal distribution of charge, resulting in the molecule having a positive end and a negative end

nonpolar

No partial charges. Do not mix with water.

hydroxyl group

OH-

Sulfhydryl

-SH

carboxyl group

A -COOH group, found in organic acids.

amino group

a chemical group consisting of a nitrogen atom bonded to two hydrogen atoms

phosphate group

A functional group consisting of a phosphorus atom covalently bonded to four oxygen atoms

Aldehyde (Carbonyl)

O\=C-H

Ketone (Carbonyl)

functioning group of C\=O where O is bonded in the middle of the carbon chain

Lipids

Energy-rich organic compounds, such as fats, oils, and waxes, that are made of carbon, hydrogen, and oxygen.

Carbohydrates

the starches and sugars present in foods

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

ester bond

The bond formed when fatty acid molecules are joined to glycerol molecules in condensation reactions.

glycosidic linkage

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

Monomer

A simple compound whose molecules can join together to form polymers

Polymer

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

Glycogen

a substance deposited in bodily tissues as a store of carbohydrates. It is a polysaccharide that forms glucose on hydrolysis.

primary protein structure

sequence of a chain of amino acids

secondary protein structure

occurs when the sequence of amino acids are linked by hydrogen bonds

tertiary structure

The third level of protein structure; the overall, three-dimensional shape of a polypeptide due to interactions of the R groups of the amino acids making up the chain.

quaternary structure

The fourth level of protein structure; the shape resulting from the association of two or more polypeptide subunits.

Catabolic

A process in which large molecules are broken down

Anabolic

A process in which large molecules are built from small molecules

Enzyme

protein that acts as a biological catalyst

Substrate

reactant of an enzyme-catalyzed reaction

Active site of an enzyme

the region of an enzyme that attaches to a substrate

competitive inhibition

substance that resembles the normal substrate competes with the substrate for the active site

noncompetitive inhibitor

A substance that reduces the activity of an enzyme by binding to a location remote from the active site, changing its conformation so that it no longer binds to the substrate.

allosteric site

The place on an enzyme where a molecule that is not a substrate may bind, thus changing the shape of the enzyme and influencing its ability to be active.

denatured protein

a protein whose structure has been changed by physical or chemical agents

induced fit model

Change in the shape of an enzyme's active site that enhances the fit between the active site and its substrate(s)

lock and key model

The model of the enzyme that shows the substrate fitting perfectly into the active site

inorganic compounds

A compound that does not contain the element carbon or contains carbon bound to elements other than hydrogen.

organic compounds

Compounds that contain carbon