BIO105 – Basic Chemistry & Molecular Biology Vocabulary

Vocabulary flashcards covering key terms from chemistry and molecular biology sections of BIO105 quizzes, including bonding, atomic structure, biomolecules, genetics, and evolutionary concepts.

Covalent Bond

A chemical bond formed when two atoms share one or more pairs of electrons.

Electron

A negatively charged sub-atomic particle; loss or gain of an electron turns an atom into an ion.

Atomic Mass (Daltons)

The combined number of protons and neutrons in an atom’s nucleus, measured in daltons (e.g., carbon ≈ 12 Da).

Electronegativity

An atom’s tendency to attract shared electrons in a covalent bond.

Non-polar Covalent Bond

A covalent bond in which electrons are shared equally because atoms have similar electronegativities (e.g., C–H).

Polar Covalent Bond

A covalent bond with unequal electron sharing due to differing electronegativities (e.g., O–H in water).

Ion

An atom or molecule with a net electric charge resulting from the loss or gain of electrons (e.g., Na⁺ after losing one electron).

Atomic Number

The number of protons in an element’s nucleus; defines the element itself (Na always has 11).

Hydrophilic

Literally “water-loving”; describes polar or charged molecules that are soluble in water.

Hydrophobic

“Water-fearing”; describes non-polar molecules that are insoluble in water but soluble in lipids.

Amino Acid

The monomer building block of proteins, containing an amino group, carboxyl group, and variable side chain.

Allele

One of multiple alternative versions of a gene found in different individuals of a species.

Ortholog

A gene in two different species that evolved from a common ancestral gene and retains the same function.

Protein Structure

The three-dimensional arrangement of amino acids in a protein; critical to its functionality.

Protein Function

The specific biological activity a protein performs, determined largely by its structure.

Evolution (Process & Pattern)

The heritable change in populations over time (process) and the observable outcomes of those changes (pattern).

Fossil

Preserved remains or traces of ancient life; evidence for the pattern of evolution.

BLAST

A bioinformatics program used to search databases for DNA or protein sequences similar to a query sequence.

Insulin Gene

The DNA sequence that encodes the insulin protein; sequence varies slightly between individuals (alleles).

Emergent Properties

New characteristics that arise at a higher level of biological organization that are not present at lower levels (e.g., a cell’s functions emerging from its molecular parts).