Flashcards in Chapter 1: The Chemical Basis of Life Deck (88)
Different atoms of the same element containing the same number of protons but a different number of neutrons.
Radioactive atoms of an element that spontaneously decay into smaller atoms, subatomic particles, and energy.
The time it takes for one-half of the nuclei in a radioactive sample to decay.
Radioisotopes that are used to follow chemicals through chemical reactions and trace their path as they move through the cells and bodies of organisms
Volumes of space around the nucleus where electrons are most likely to be found.
Electrons located in outermost s and p orbitals that determine an atom's chemical behavior.
Intramolecular Forces of Attraction
The covalent bond that holds the atoms of a molecule together, and the ionic bond that holds ions together in a salt.
A measure of an atom's ability to attract a shared electron pair when it is participating in a covalent bond.
For atoms, a modification of the valence orbitals that changes the orientation of the valence electrons; in genetic coding, complementary base pairing between strands of nucleic acids via hydrogen bonding.
Chemical bonds between molecules.
Van der Waals Forces
Intermolecular forces of attraction including London Forces, dipole-dipole forces and hydrogen bonds.
Describes liquids that dissolve into one another.
Describes liquids that form separate liquids instead of dissolving.
Having an aversion to water; the tendancy of nonpolar molecules to exclude water.
Having an affinity to water; the tendency of polar and ionic substances to dissolve in water.
The reaction of an acid and a base to produce water and salt.
Acids that ionize completely in aqueous solution.
Bases that ionize completely in aqueous solution.
Acids that partially ionize in aqueous solution.
Bases that partially ionize in aqueous solution.
A condition in which opposing reactions occur at equal rates.
Chemical systems containing a substance that can donate H+ ions when they are required and containing a substance that can remove H+ ions when there are too many in a solution.
The difference between the energy level of the transition state and the potential energy of reacting molecules.
A substance that binds to an allosteric site on an enzyme and stabilizes the protein conformation that keeps all the active site available to their substrates.
The location where the substrate binds to an enzyme.
Adenosine Triphosphate (ATP)
A nucleotide derivative that acts as the primary energy-transferring molecule in living organisms.
A substance that binds to an allosteric site on an enzyme and stabilizes the inactive form of the enzyme.
Receptor sites, some distance from the active site of certain enzymes, that bind substances that may inhibit or stimulate an enzyme’s activity.
Alpha (α) Helix
A type of polypeptide secondary structure characterized by a tight coil that is stabilized by hydrogen bonds.