INTRODUCTION TO BIOCHEMISTRY
atom - Answer- The basic unit of matter.
protons - Answer- subatomic particle with positive charge found in the nucleus of an atom
neutrons - Answer- subatomic particle with no charge (neutral) found in the nucleus of an atom
electrons - Answer- subatomic particle with negative charge found in energy levels outside the
nucleus
valence electrons - Answer- electrons found in the outermost energy level that are involved with
bonding
element - Answer- pure substance, consisting of only 1 type of atom (like sodium)
compound - Answer- substance formed from the chemical combination of two or more elements in
definite proportions
isotope - Answer- atoms of the same element with different numbers of neutrons
ion - Answer- charged atom formed when atom either loses electron(s) (and becomes + charged)
or gains electron(s) becoming negatively charged
ionic bonds - Answer- involve a transfer of electrons and produces ions. Happens only between
metals and nonmetals
covalent bonds - Answer- electrons are shared between atoms. Occurs between two nonmetals or
in diatomic molecules.
chemical reaction - Answer- process by which atoms or groups of atoms in substances are
reorganized into different substances
chemical equation - Answer- chemical formulas and symbols describe the substances in the
reaction and arrows indicate the process of change
reactants - Answer- starting substances in a chemical reaction found on the left side of the (arrow)
equation
products - Answer- substances formed during the reaction and found on the right side of the
(arrow) chemical equation
activation energy - Answer- the minimum amount of energy needed for reactants to form products
in a chemical reaction
enzyme - Answer- a special type of protein called a catalyst because it speeds up a chemical
reactions in cells by lowering the activation energy
atom - Answer- The basic unit of matter.
protons - Answer- subatomic particle with positive charge found in the nucleus of an atom
neutrons - Answer- subatomic particle with no charge (neutral) found in the nucleus of an atom
electrons - Answer- subatomic particle with negative charge found in energy levels outside the
nucleus
valence electrons - Answer- electrons found in the outermost energy level that are involved with
bonding
element - Answer- pure substance, consisting of only 1 type of atom (like sodium)
compound - Answer- substance formed from the chemical combination of two or more elements in
definite proportions
isotope - Answer- atoms of the same element with different numbers of neutrons
ion - Answer- charged atom formed when atom either loses electron(s) (and becomes + charged)
or gains electron(s) becoming negatively charged
ionic bonds - Answer- involve a transfer of electrons and produces ions. Happens only between
metals and nonmetals
covalent bonds - Answer- electrons are shared between atoms. Occurs between two nonmetals or
in diatomic molecules.
chemical reaction - Answer- process by which atoms or groups of atoms in substances are
reorganized into different substances
chemical equation - Answer- chemical formulas and symbols describe the substances in the
reaction and arrows indicate the process of change
reactants - Answer- starting substances in a chemical reaction found on the left side of the (arrow)
equation
products - Answer- substances formed during the reaction and found on the right side of the
(arrow) chemical equation
activation energy - Answer- the minimum amount of energy needed for reactants to form products
in a chemical reaction
enzyme - Answer- a special type of protein called a catalyst because it speeds up a chemical
reactions in cells by lowering the activation energy
