Quiz 5: Enzymes

An ion which has lost two electrons has a charge of:

+2

The weak type of bonding which attracts molecules to molecules is:

hydrogen

Amino acids are the building blocks of

proteins

The total number of elements that have been identified is:

118

The number of atoms in a molecule of ammonia 3(NH3) is:

12

A strong acid has a pH approaching:

0

The energy required to start a chemical reaction is called:

activation energy

The four classes of organic molecules are

carbohydrates, lipids, nucleic acids,and proteins

The elements most often found in organic molecules are

carbon, hydrogen, nitrogen, and oxygen

Non protein substance (such as vitamins and some metal ions) which need to be present for enzymes to function are called

cofactors

Carbon forms

covalent bonds

Protein catalysts which cause reactions to occur at temperatures and pH values which are common to living cells are called

enzymes

Acid + base yields salt + water is an example of an:

exchange reaction

An organism can live without enzymes

false

Because enzymes have high specificity, fewer than fifteen are required by any organism

false

Enzyme molecules react with reactants to produce substrate molecules

false

Organic catalysts are called polysaccharides

false

The atomic mass of an atom with six electrons, eight neutrons, and six protons is:

fourteen

The simplest structured unit of a compound is a:

molecule

The largest organic molecules are

nucleic acids

covalent

sharing of electrons

The substance upon which an enzyme acts is called the

substrate

ionic

transfer of electrons

Chemical reactions in cells are faster than the same reactions outside cells

true

The effect of a catalyst is the reduction of activation energy required to initiate a chemical reaction

true

Enzymes are produced only

within an active cell