General Biochemistry terms

Atom

The basic unit of matter.

Element

A substance consisting of only one type of atom.

Proton

Positively charged subatomic particles in the nucleus.

Neutron

Neutrally charged subatomic particles orbiting the nucleus.

Electron

Negatively charged subatomic particles orbiting the nucleus

Atomic Number

Number of protons in an atom (defines the element).

Atomic Mass

Total mass of protons, neutrons, and electrons in an atom.

Isotope

Atoms of the same element with different numbers of neutrons.

Chemical Bond

Forces that hold atoms together in molecules

Covalent Bond

A strong bond formed by the sharing of electrons between atoms

Polar Covalent Bond

Unequal sharing of electrons resulting in charged ions.

Nonpolar Covalent Bond

Equal sharing of electrons

Ionic Bond

A Bond formed by the transfer of electrons resulting in charged ions

Ion

An atom or molecule with a net electrical charge

Hydrogen Bond

A weak attraction between a partially positive hydrogen atom in one molecule and a partially negative atom (like oxygen or nitrogen) in another molecule.

C - Carbon

The backbone of all organic molecules (carbohydrates, lipids, proteins, and nucleic acids) due to its ability to form four stable covalent bonds.

H - Hydrogen

A crucial component of water and all organic molecules. It’s involved in hydrogen bonding, which is vital for the properties of water and the structure of macromolecules

N - Nitrogen

Essential for the formation of proteins (as part of amino acids) and nucleic acids (as part of nitrogenous bases in DNA and RNA).

O - Oxygen

A major component of water and all organic molecules. It’s critical for cellular respiration, where it acts as the final electron acceptor.

P - Phosphorous

Key component of nucleic acid (in the phosphate backbone of DNA and RNA) and ATP (adenosine triphosphate), the primary energy currency of the cell.

S - Sulfur

Found in certain amino acids (cysteine and methionine), which are crucial for the proper folding and structure of proteins (disulfide bonds).

Calcium (Ca)

Important for bone formation, muscles contraction, nerve transmission, and cell signaling.

Potassium (K)

Essential for nerve impulses and muscle function.

Sodium (Na)

Crucial for nerve impulses and maintaining water balence.

Chlorine (Cl)

Important for fluid balance and nerve function.

Magnesium (Mg)

A cofactor in many enzymatic reactions.

Iron (Fe)

A component of hemoglobin (for oxygen transport) and various enzymes.

Iodine (I)

Required for thyroid hormone synthesis.