Basic Understanding of DNA, RNA, and Atomic Structure

Nucleic Acids

• Thymine is only found in DNA, while Uracil is only found in RNA.
• DNA is double-stranded, whereas RNA is single-stranded.

Atomic Structure

• Protons have a positive charge and are found in the nucleus of an atom.
• Neutrons have no charge and are found in the nucleus of an atom, with a similar mass to protons.
• Electrons are small particles with a negative charge, found in the orbital "cloud" outside the nucleus.
• Atomic number is the number of protons in an atom.
• Atomic mass is the number of protons and neutrons in an atom.

Isotopes

• Isotopes are different atoms of the same element, with the same number of protons and electrons, but a different number of neutrons.
• Isotopes have identical chemical characteristics but different atomic masses.
• Examples of isotopes include Carbon-12, Carbon-13, and Carbon-14.

Chemical Bonds

• Chemical bonds hold atoms together to form molecules and compounds.
• Covalent bonds are formed by sharing electrons between atoms.
• Ionic bonds are formed by the transfer of electrons, resulting in attraction between a positively charged and negatively charged atom.
• Hydrogen bonds are weak bonds between a hydrogen atom and an oxygen or nitrogen atom.

Covalent Bonds

• Covalent bonds involve sharing electrons to complete outer energy shells.
• Nonpolar covalent bonds involve equal sharing of electrons between atoms.
• Polar covalent bonds involve unequal sharing of electrons between atoms.
• Examples of covalent bonds include single, double, and triple covalent bonds.

Hydrogen Bonds

• Hydrogen bonds occur between molecules and alter the shapes and properties of molecules.
• Examples include surface tension of water.

Ionic Bonds

• Ionic bonds form between charged atoms (ions) with opposite charges.
• Ions are atoms with either a positive charge (cations) or a negative charge (anions).
• Ionic bonds form due to attraction between positive and negative charges.

Compounds

• Inorganic compounds have 0 or 1 carbon atoms.
• Organic compounds contain 2 or more carbon atoms.
• Electrolytes are soluble inorganic molecules, like NaCl, whose + and - ions conduct an electric current.
• Buffers are compounds that regulate the pH of a solution by removing or replacing H+ ions.

Proteins

• Proteins are composed of chains of amino acid monomers.
• Amino acids form amino acid chains known as peptides.