Biology self test five

the weak type of bonding which attracts molecules to molecules is

hydrogen

difference between covalent and ionic bonding

Ionic bonding involves the transfer of electrons from atom to atom. covalent bonding involves the sharing of electrons

Amnio acids are building blocks of

Proteins

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

+2

a strong acid has a pH approaching

0

number of elements that have been identified is

109

What's the necessary of cofactors

Cofactors are nonprotein substances which must be present for enzymes to function as a catalysts

What are enzymes?

Enzymes are proteins catalysts which causes reactions to occur at temperatures and pH values common to living cells

(TorF)enzyme molecules react with reactants to produce substrate molecules

False

cofactor:

a nonprotein substance which allows an enzyme to function; an activator of an enzyme

A catalyst is:

a substance which accelerates a chemical reaction

the energy required to start a chemical reaction is called

activation energy

Four classes of organic molecules are

carbohydrates, lipids, proteins, nucleic acids

Carbohydrates contain the elements ______ ______ and _______

carbon, hydrogen, and oxygen

elements found most often in organic molecules are

carbon, hydrogen, nitrogen, and oxygen

carbon forms ___ bonds

covalent

acid + base -> salt + water is an example of a/an _______ reaction

exchanged

Because enzymes have high specificity, fewer than 15 are required in an organism

false

organic catalysts are called polysaccharides

false

number of atoms in a molecule of ammonia (NH3) is

four

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

fourteen

the simplest structured unit of the water compound is one

molecule

the largest organic molecules are

nucleic acids

Draw and label

p=protons n=neutrons

if one product of a reversible chemical reaction is removed, the rate of reaction __________

slows

that part of the enzyme which takes part in digestion is the

surface

substrate:

that substance upon which an enzyme works; is chemically changed in a reaction

Optimial:

the best possible

active sites:

those specific parts of an enzyme molecule at which substrates interact with enzyme

chemical reaction in cells are faster than the same reactions outside cells.

true

enzymes comprise only a small minority of cellular mass

true

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

true