AP Biology Semester 1 Review
matter
any substance in the universe that has mass and occupies space
atoms
small particles that make up all matter
electrons
negatively charged subatomic particles that are transferred and shared between atoms
ion
a charged particle
acid
any substance that dissociates in water to increase the concentration of H+ ions; pH values of acids
are from 1-7
base
any substance that combines with H+ ions when dissolved in water; pH values from 7-14
oxidation
the loss of an electron
reduction
the gain of an electron
molecules
groups of atoms held together by energy in a stable association
chemical bond
joins atoms in a molecule
ionic bond
attraction between ions of opposite charge in an ionic compound
covalent bond
a stable chemical bond formed when two atoms share one or more pairs of electrons
pH
indicates concentration of hydrogen ions in a solution (the more H+ ions a solution produces, the
lower its pH; pH scale- less than 7 is acidic, 7 is neutral, above 7 is basic)
chemical reactions
,formation and breaking of chemical bonds
hydrogen bonds
the weak bond bridging hydrogen atoms and atoms of the opposite charge
adhesion
attraction of water molecules to other molecules
cohesion
attraction of water molecules to water molecules
reactants
original molecules before the reaction starts
products
molecules resulting from the chemical reaction
hydrophobic
when nonpolar molecules do not form hydrogen bonds with water ("fearing water")
hydrophilic
when polar molecules readily form hydrogen bonds with water ("water-loving")
hydrocarbons
biological molecules consisting only of carbon and hydrogen
functional groups
specific groups of atoms with definite chemical properties that they retain no matter where they
occur
dehydration synthesis
condensation reaction in which the -OH and H groups are removed during the synthesis of a new
molecule- water is removed
hydrolysis
process in which a hydrogen atom is attached to one subunit and a hydroxyl group to the other- water
is added
denaturation
process in which a protein's shape is changed due to a change in its environment- pH change,
temperature, or ionic concentration of surrounding solution affect it
Enzyme
Biological catalyst made of amino acids.
, Substrate
Reactant an enzyme catalyzes
Active Site
structure on the enzyme
Reactants
The molecules needed for a chemical reaction to occur
Products
Molecules that are made when a chemical reaction is over
Activation Energy
The amount of energy needed for a reaction to occur.
Heat of Reaction
The difference in energy between the reactants and products of a chemical reaction
Exothermic
a reaction that has a "-" heat of reaction b/c it releases more energy that it stores
Endothermic
a reaction that has a "+" heat of reaction and stores more energy than it releases.
Catalyst
Speeds up a chemical reaction
Variables that effect enzyme reaction rate
Temperature, pH, enzyme concentration, substrate concentration
denature
enzyme becomes "inactive" due to changes in the active site structure
enzyme specificity
enzyme only bonds to one substrate due to shape of active site
cell membrane
regulates movement of materials in and out of cells, maintains cell shape and allows cells to
communicate with each other
smooth endoplasmic reticulum
makes or synthesizes lipids, detoxification of drugs/medicines
matter
any substance in the universe that has mass and occupies space
atoms
small particles that make up all matter
electrons
negatively charged subatomic particles that are transferred and shared between atoms
ion
a charged particle
acid
any substance that dissociates in water to increase the concentration of H+ ions; pH values of acids
are from 1-7
base
any substance that combines with H+ ions when dissolved in water; pH values from 7-14
oxidation
the loss of an electron
reduction
the gain of an electron
molecules
groups of atoms held together by energy in a stable association
chemical bond
joins atoms in a molecule
ionic bond
attraction between ions of opposite charge in an ionic compound
covalent bond
a stable chemical bond formed when two atoms share one or more pairs of electrons
pH
indicates concentration of hydrogen ions in a solution (the more H+ ions a solution produces, the
lower its pH; pH scale- less than 7 is acidic, 7 is neutral, above 7 is basic)
chemical reactions
,formation and breaking of chemical bonds
hydrogen bonds
the weak bond bridging hydrogen atoms and atoms of the opposite charge
adhesion
attraction of water molecules to other molecules
cohesion
attraction of water molecules to water molecules
reactants
original molecules before the reaction starts
products
molecules resulting from the chemical reaction
hydrophobic
when nonpolar molecules do not form hydrogen bonds with water ("fearing water")
hydrophilic
when polar molecules readily form hydrogen bonds with water ("water-loving")
hydrocarbons
biological molecules consisting only of carbon and hydrogen
functional groups
specific groups of atoms with definite chemical properties that they retain no matter where they
occur
dehydration synthesis
condensation reaction in which the -OH and H groups are removed during the synthesis of a new
molecule- water is removed
hydrolysis
process in which a hydrogen atom is attached to one subunit and a hydroxyl group to the other- water
is added
denaturation
process in which a protein's shape is changed due to a change in its environment- pH change,
temperature, or ionic concentration of surrounding solution affect it
Enzyme
Biological catalyst made of amino acids.
, Substrate
Reactant an enzyme catalyzes
Active Site
structure on the enzyme
Reactants
The molecules needed for a chemical reaction to occur
Products
Molecules that are made when a chemical reaction is over
Activation Energy
The amount of energy needed for a reaction to occur.
Heat of Reaction
The difference in energy between the reactants and products of a chemical reaction
Exothermic
a reaction that has a "-" heat of reaction b/c it releases more energy that it stores
Endothermic
a reaction that has a "+" heat of reaction and stores more energy than it releases.
Catalyst
Speeds up a chemical reaction
Variables that effect enzyme reaction rate
Temperature, pH, enzyme concentration, substrate concentration
denature
enzyme becomes "inactive" due to changes in the active site structure
enzyme specificity
enzyme only bonds to one substrate due to shape of active site
cell membrane
regulates movement of materials in and out of cells, maintains cell shape and allows cells to
communicate with each other
smooth endoplasmic reticulum
makes or synthesizes lipids, detoxification of drugs/medicines
