Elements of Life:
● Hydrogen and carbon are key elements that form the basis of biological
molecules.
Isotopes and Radioisotopes:
● Isotopes are atoms of the same element with different numbers of neutrons.
● Radioisotopes are unstable isotopes that undergo radioactive decay over time by
emitting radiation.
Organic Molecules:
● Organic molecules are carbon-based, with carbon atoms bonded to hydrogen.
● Carbon's valence electron configuration determines its bonding behavior and the
structure of organic molecules.
Intramolecular Forces:
● Non-polar covalent bonds form when two atoms with similar electronegativity
share electrons equally, resulting in a nonpolar molecule.
● Intramolecular forces hold atoms together within a molecule.
Intermolecular Forces:
● Intermolecular forces occur between atoms of different molecules and determine
how molecules interact with each other.
Hydrogen Bonding:
● Hydrogen bonding is a weak association between an atom with partial negative
charge and a hydrogen atom with partial positive charge.
● Hydrogen bonding occurs between slightly positive hydrogen atoms and slightly
negative oxygen atoms, for example.
● Hydrogen bonds are weaker than ionic or covalent bonds.
Hydrophobic Interactions:
● Hydrophobic interactions occur between nonpolar molecules and polar molecules
like water.
● Nonpolar molecules tend to clump together in the presence of polar molecules,
resulting in the hydrophobic effect.
Ions in Biological Systems:
● Ions are atoms or groups of atoms that have gained or lost electrons, resulting in
a positive or negative charge.
● Cations are positively charged ions, while anions are negatively charged ions.
● Hydrogen and carbon are key elements that form the basis of biological
molecules.
Isotopes and Radioisotopes:
● Isotopes are atoms of the same element with different numbers of neutrons.
● Radioisotopes are unstable isotopes that undergo radioactive decay over time by
emitting radiation.
Organic Molecules:
● Organic molecules are carbon-based, with carbon atoms bonded to hydrogen.
● Carbon's valence electron configuration determines its bonding behavior and the
structure of organic molecules.
Intramolecular Forces:
● Non-polar covalent bonds form when two atoms with similar electronegativity
share electrons equally, resulting in a nonpolar molecule.
● Intramolecular forces hold atoms together within a molecule.
Intermolecular Forces:
● Intermolecular forces occur between atoms of different molecules and determine
how molecules interact with each other.
Hydrogen Bonding:
● Hydrogen bonding is a weak association between an atom with partial negative
charge and a hydrogen atom with partial positive charge.
● Hydrogen bonding occurs between slightly positive hydrogen atoms and slightly
negative oxygen atoms, for example.
● Hydrogen bonds are weaker than ionic or covalent bonds.
Hydrophobic Interactions:
● Hydrophobic interactions occur between nonpolar molecules and polar molecules
like water.
● Nonpolar molecules tend to clump together in the presence of polar molecules,
resulting in the hydrophobic effect.
Ions in Biological Systems:
● Ions are atoms or groups of atoms that have gained or lost electrons, resulting in
a positive or negative charge.
● Cations are positively charged ions, while anions are negatively charged ions.
