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