Honors Anatomy Chapter 2: Chemical Basis of Life

Vocabulary flashcards covering the chemical foundations of anatomy and physiology, including atomic structure, chemical bonds, acid-base balance, and the major classes of organic macromolecules.

Matter

Anything that has mass and takes up space.

Mass

The amount of matter in an object.

Weight

The force of gravity acting on a mass.

Isotopes

Atoms of an element that have the same number of protons and the same atomic number, but differing numbers of neutrons and different atomic weights.

Cation

An atom that has lost electrons and acquired a positive charge.

Anion

An atom that has gained electrons and acquired a negative charge.

Covalent Bond

A chemical bond formed when atoms share pairs of electrons.

Ionic Bond

A chemical bond formed when atoms gain or lose electrons.

Biochemistry

The branch of chemistry devoted to the study of living organisms.

Bulk Elements

The six elements required by the human body in large quantities: carbon, hydrogen, oxygen, nitrogen, phosphorus, and sulfur.

Trace Elements

Elements required by the body in small amounts.

Ultratrace Elements

Elements required by the body in very small amounts.

Inert (Noble) Atom

An atom whose outermost electron shell is completely full, rendering it non-reactive with other atoms.

Polar Molecule

A molecule that results from the uneven sharing of electrons within covalent bonds.

Hydrogen Bond

A weak attraction that holds one water molecule to an adjacent water molecule.

Molecular Formula

A notation stating the specific elements involved in a compound and the exact number of each element present.

Structural Formula

A diagrammatic representation showing how the atoms of elements are arranged within a molecule.

Alkalosis

A clinical condition occurring when blood pH rises above the normal range of $7.35$ to $7.45$.

Acidosis

A clinical condition occurring when blood pH falls below the normal range of $7.35$ to $7.45$.

Buffers

Chemical substances that resist shifts in pH.

Catalyst

A substance that alters the rate or speed of a chemical reaction without influencing its direction.

Synthesis Reaction

A chemical reaction in which two or more atoms or simpler molecules combine to produce a more complex molecule.

Exchange Reaction

A reaction where two different types of molecules trade components, represented as $AB + CD \rightarrow AD + CB$.

Acid

A substance that releases ions and has a higher concentration of hydrogen ions ($H^+$) than hydroxide ions ($OH^-$).

Base

A substance that has a higher concentration of hydroxide ions ($OH^-$) than hydrogen ions ($H^+$).

Electrolytes

Substances that release ions when dissolved in water.

Salts

Compounds formed as products when acids and bases interact.

Steroids

Lipid structures composed of connected rings of carbon atoms, exemplified by cholesterol.

Organic Compounds

Chemical compounds that contain both carbon and hydrogen.

Inorganic Compounds

Chemical compounds that do not contain both carbon and hydrogen.

Non-electrolytes

Organic compounds that dissolve in water without releasing ions.

Phospholipid

A lipid molecule composed of $1$ glycerol, $2$ fatty acids, and $1$ phosphate group, possessing a water-soluble (hydrophilic) head and insoluble (hydrophobic) tails.

Monosaccharide

A simple carbohydrate composed of a single sugar unit, such as glucose.

Disaccharide

A complex carbohydrate composed of two linked sugar units.

Saturated Lipid

A lipid that contains zero ($0$) double bonds between carbon atoms in its hydrocarbon chain.

Unsaturated Lipid

A lipid that contains one or more double bonds between carbon atoms.

Triglyceride

The most common form of fat in the body, composed of $1$ glycerol molecule bonded to $3$ fatty acids.

Conformation

The unique three-dimensional shape of a protein that determines its biological function.

Glycoprotein

A macromolecule formed when a protein binds with a carbohydrate.

Enzyme

A protein that acts as a biological catalyst by lowering the activation energy of a reaction.

Peptide Bond

A covalent bond formed between the amino group of one amino acid and the carboxyl group of another.

Polypeptide

A polymer consisting of a chain of more than three linked amino acids.

Gene

A short sequence of DNA that codes for a specific trait, with humans possessing approximately $20{,}000$ in total.

DNA (Deoxyribonucleic Acid)

A double-stranded nucleic acid that contains deoxyribose sugar and thymine, responsible for storing genetic information and instructions.

RNA (Ribonucleic Acid)

A usually single-stranded nucleic acid containing ribose sugar and uracil that carries instructions for putting amino acids in order to synthesize proteins.

Nucleotide

The fundamental building block of nucleic acids, consisting of a $5$-carbon sugar, a nitrogenous base, and a phosphate group.

Denaturation

The disruption or unfolding of a protein's normal three-dimensional shape caused by heat, extreme pH, or high salt concentrations, rendering it non-functional.