Basic Biochemistry and Molecular Biology Review

Vocabulary flashcards covering atomic structure, bonding, solutions, pH, biomolecules, nucleic acids, and energy metabolism from the lecture.

Proton

Positively charged subatomic particle located in an atom’s nucleus.

Neutron

Neutral subatomic particle in the nucleus; differing numbers create isotopes.

Electron

Negatively charged subatomic particle orbiting the nucleus with little mass.

Nucleus

Dense atomic core containing protons and neutrons; source of atomic mass.

Isotope

Variant of an element with the same protons but different neutron count.

Valence Electron

Electron in an atom’s outer shell that participates in bonding.

Polar Molecule

Molecule with uneven electron distribution; water-soluble.

Nonpolar Molecule

Molecule with even electron distribution; insoluble in water.

Electronegativity

Measure of an atom’s ability to attract shared electrons; drives polarity.

Ionic Bond

Chemical bond formed by complete electron transfer and attraction of oppositely charged ions.

Covalent Bond

Chemical bond created by sharing electron pairs between atoms.

Solvent

Larger component of a solution that dissolves the solute (e.g., water).

Solute

Smaller component dissolved in a solvent.

Acid

Substance that donates hydrogen ions; high [H⁺] and low pH.

pH Scale

Logarithmic 0–14 scale measuring acidity/alkalinity; each unit is a 10-fold change in [H⁺].

Organic Compound

Carbon-based molecule, often containing H, O, and N; foundation of life chemistry.

Monosaccharide

Single sugar unit serving as a carbohydrate building block.

Lipid

Hydrophobic biomolecule that includes triglycerides, phospholipids, waxes, and steroids.

Nucleotide

Monomer of nucleic acids: nitrogen base + pentose sugar + phosphate group.

Purine

Double-ring nitrogen base; adenine (A) or guanine (G).

Pyrimidine

Single-ring nitrogen base; cytosine (C), thymine (T), or uracil (U).

Polymer

Large molecule composed of repeating monomer subunits.

Hormone

Chemical messenger that coordinates physiology and behavior.

Enzyme

Biological catalyst that speeds up biochemical reactions.

Glycogen

Glucose storage polysaccharide found in animals.

Cellulose

Plant structural polysaccharide indigestible to humans.

Amino Acid

Protein monomer containing an amino group, carboxyl group, hydrogen, and R group on an alpha carbon.

Alpha Carbon

Central carbon in an amino acid bonded to the amino, carboxyl, hydrogen, and R groups.

Carboxyl Group

–COOH functional group that acts as an acid in amino acids.

Phosphate Backbone

Repeating sugar–phosphate chain providing DNA/RNA structure and negative charge.

DNA

Double-helical nucleic acid storing genetic information with bases A, T, C, and G.

RNA

Single-stranded nucleic acid that translates genetic code into proteins; contains A, U, C, G.

Adenosine Triphosphate (ATP)

Primary energy currency of the cell; adenine + ribose + three phosphate groups.