Biochemistry Grade 12 Vocabulary

Question 1

a chemical that compensates for pH changes in a solution by accepting or donating H+ ions

Answer 1

buffer

Question 2

a process in which small subunits are linked to form a large molecule

Answer 2

polymerization

Question 3

an ion that has a negative charge

Answer 3

anion

Question 4

a non-protein group that binds to an enzyme and is essential for catalytic activity

Answer 4

cofactor

Question 5

a chain of amino acid subunits that are connected by covalent bonds

Answer 5

peptide

Question 6

the amount of thermal energy required to raise the temperature of a given quantity of a substance by 1 degree C

Answer 6

specific heat

Question 7

a covalent bond that links amino acids

Answer 7

peptide bond

Question 8

a peptide with more than 50 amino acids

Answer 8

polypeptide

Question 9

a chemical reaction in which subunits of a larger molecule are joined by the removal of water; also called a condensation reaction

Answer 9

dehydration reaction

Question 10

a fat with one or more double bonds in the fatty acid chain (monounsaturated = one double bond; polyunsaturated = more than one double bond)

Answer 10

unsaturated fat

Question 11

the loss of both the structure and function of a protein

Answer 11

denaturation

Question 12

a small molecule that can bind chemically to other molecules

Answer 12

monomer

Question 13

a bond that results from the attraction between two oppositely charged atoms or molecules

Answer 13

ionic bond

Question 14

a type of fat in which the fatty acid chains have single bonds

Answer 14

saturated fat

Question 15

a lipid with a structure consisting of four fused hydrocarbon rings forming the bulky steroid structure

Answer 15

cholesterol

Question 16

the force of attraction between two molecules

Answer 16

intermolecular force

Question 17

a molecule that is composed of hundreds to thousands of monosaccharides linked together

Answer 17

complex carbohydrate

Question 18

polar or charged molecules that are strongly attracted to water

Answer 18

hydrophilic molecules

Question 19

oriented in opposite directions

Answer 19

antiparallel

Question 20

Non-polar molecules that are not strongly attracted to water

Answer 20

hydrophobic molecules

Question 21

-COOH, with a double bond between the carbon and one of the oxygens

Answer 21

carboxyl group

Question 22

the simplest form of carbohydrate, consisting of a single sugar unit; a building block for more complex carbohydrates

Answer 22

monosaccharide

Question 23

a biological catalyst, usually a protein, that speeds up a chemical reaction

Answer 23

enzyme

Question 24

a biomolecule that consists of carbon, oxygen, and hydrogens, usually with a hydrogen:oxygen atom ratio of 2:1

Answer 24

carbohydrate

Question 25

a group of atoms that affects the function of a molecule by participating in chemical reactions

Answer 25

functional group

Question 26

C3H8O3; its chemical structure consists of three hydroxyl (-OH) group attached to the carbon atoms

Answer 26

glycerol

Question 27

an ion that has a positive charge

Answer 27

cation

Question 28

a link that is formed between nucleotides by a phosphate bridge

Answer 28

phosphodiester bond

Question 29

a model of enzyme activity that describes how an enzyme changes shape to better accommodate a substrate

Answer 29

induced-fit model

Question 30

a large molecule that is formed when monomers link together chemically in a chain

Answer 30

polymer

Question 31

a non-polar compound that is made mostly of carbon and hydrogen

Answer 31

lipid

Question 32

the process in which a molecule spontaneously dissociates into ions

Answer 32

autoionization

Question 33

a reaction in which a molecule loses electrons

Answer 33

oxidation

Question 34

three fatty acid chains linked to a glycerol molecule

Answer 34

triglyceride

Question 35

a molecule that has the same composition as another, but a different arrangement of atoms

Answer 35

isomer

Question 36

a lipid that consists of two fatty acids and a phosphate group bound to glycerol

Answer 36

phospholipid

Question 37

the regulation of a pathway by one of the products of this pathway

Answer 37

feedback inhibition

Question 38

the attractive force between a partially positively charged hydrogen atom and a partially negatively charged atom in another molecule

Answer 38

hydrogen bond

Question 39

a bond between two monosaccharides

Answer 39

glycosidic bond

Question 40

a region of space that is occupied by electrons located around the nucleus of the atom

Answer 40

orbital

Question 41

partial positive or negative charge at the ends of a molecule

Answer 41

polarity

Question 42

the measure of an atom's attraction to shared electrons

Answer 42

electronegativity

Question 43

a large molecule that consists of many amino acid subunits that are joined together by peptide bonds folded into a specific three-dimensional shape

Answer 43

protein

Question 44

a carbohydrate molecule that is made from two monosaccharide units

Answer 44

disaccharide

Question 45

a bond between two atoms, made up of unequally shared electrons

Answer 45

polar covalent bond

Question 46

a binding site on an enzyme that binds regulatory molecules

Answer 46

allosteric site

Question 47

a reaction in which an acid and a base combine to create a salt and water

Answer 47

neutralization reaction

Question 48

a molecule that contains a carboxyl group and an amino group; serves as the monomer subunit of proteins

Answer 48

amino acid

Question 49

a blueprint for proteins that are synthesized in cells; stores hereditary information

Answer 49

nucleic acid

Question 50

a chemical reaction in which water is used as a reactant to split a larger molecule into smaller subunits

Answer 50

hydrolysis reaction

Question 51

the regulation of one site of a protein by binding to another site on the same protein

Answer 51

allosteric regulation

Question 52

the building block of nucleic acids; consists of a 5-carbon sugar, a nitrogenous base, and one to three phosphate groups

Answer 52

nucleotide

Question 53

a molecule that consists of a carboxyl group and a hydrocarbon chain

Answer 53

fatty acid

Question 54

a lipid that is formed when long fatty acid chains are joined to alcohols or carbon rings

Answer 54

wax

Question 55

an electron in the outermost energy level or shell of an atom

Answer 55

valence electron

Question 56

a chemical compound derived from an acid in which at least one hydroxyl group is replaced by an alkoxy group (usually derived from a carboxylic acid and an alcohol)

Answer 56

ester

Question 57

a lipid that is composed of four carbon rings

Answer 57

steroid

Question 58

an organic compound in which a hydroxyl group (-OH) is bound to a carbon atom, which in turn is bound to other hydrogen and/or carbon atoms

Answer 58

alcohol

Question 59

a situation in which molecules bind to an enzyme at a site that is not the active site, thus blocking enzyme activity

Answer 59

noncompetitive inhibition

Question 60

an organic molecule that acts as a cofactor of an enzyme

Answer 60

coenzyme

Question 61

a molecule that contains many linked monosaccharides

Answer 61

polysaccharide molecule

Question 62

an electron transfer reaction

Answer 62

redox reaction

Question 63

a situation in which a competitor substance binds to a normal substrate binding site to block enzyme activity

Answer 63

competitive inhibition

Question 64

very weak attractions between two molecules, or parts of molecules, when they are close together

Answer 64

van der Waals forces

Question 65

a reaction in which a molecule gains electrons

Answer 65

reduction