Chemical Composition of the Body

These flashcards cover essential vocabulary and concepts from the lecture notes on the chemical composition of the body, helping to reinforce understanding and preparation for the exam.

Atom

Smallest unit of an element made up of protons, neutrons, and electrons.

Valence electrons

Electrons in the outer shell of an atom that participate in chemical reactions.

Chemical bond

An interaction where atoms give, take, or share electrons to achieve a full outer orbital.

Covalent bond

A type of chemical bond where two or more atoms share pairs of valence electrons.

Ionic bond

A chemical bond formed when one atom gives electrons to another, creating ions.

Hydrogen bond

A weak attraction between polar molecules, important for the structure of water and macromolecules.

Hydrophilic

Substances that are soluble in water; polar molecules and ions.

Hydrophobic

Substances that do not dissolve in water; typically nonpolar molecules.

pH scale

A scale from 0 to 14 used to quantify the acidity or alkalinity of a solution.

Macromolecules

Large organic molecules such as carbohydrates, lipids, proteins, and nucleic acids.

Carbohydrates

Sugars and starches that serve as a major source of energy; contain C, H, and O in a 1:2:1 ratio.

Proteins

Diverse molecules made of amino acids that have structural, enzymatic, and regulatory functions.

Amino acid

Building block of proteins, containing an amino group, carboxyl group, and a side chain.

Nucleotide

Building block of nucleic acids consisting of a sugar, a phosphate group, and a nitrogenous base.

DNA

Deoxyribonucleic acid, a double-helix molecule that contains genetic information.

RNA

Ribonucleic acid, usually single-stranded, involved in protein synthesis and contains uracil instead of thymine.

Peptide bond

Covalent bond linking the carboxyl group of one amino acid to the amino group of another.