Chemistry and Biological Molecules - Anatomy Lecture 5-19-26

A complete set of vocabulary flashcards covering basic chemistry, atomic structure, isotopes, reaction types, pH, and the major classes of organic macromolecules as detailed in the lecture.

Biochemistry

The study of the chemical processes within and relating to living organisms.

Matter

Anything that has mass and takes up space, existing in three states: solid, liquid, or gas.

Protons

Subatomic particles located in the nucleus of an atom that carry a positive charge.

Neutrons

Subatomic particles located in the nucleus of an atom that carry no electrical charge.

Electron

A subatomic particle that orbits the nucleus and carries a negative charge.

Valence electrons

The electrons located in the outermost shell of an atom that determine its chemical bonding properties.

Isotopes

Varieties of an element that differ from one another only in the number of neutrons and therefore in atomic weight.

Deuterium ($^2H$)

An isotope of hydrogen containing $1$ proton, $1$ neutron, and $1$ electron.

Tritium ($^3H$)

An isotope of hydrogen containing $1$ proton, $2$ neutrons, and $1$ electron.

Anion

A particle that gains electrons and acquires a negative charge ($-$).

Cation

A particle that loses electrons and acquires a positive charge ($+$).

Electrolytes

Substances that ionize in water and form solutions capable of conducting electric current.

Major elements

The four chemical elements ($C, H, O, N$) that make up the vast majority of the body.

Lesser elements

A group of elements including $Ca, P, K, S, Na,$ and $Fe$ found in smaller amounts in the body.

Trace elements

Elements found in very minute amounts in the body, such as $Cu$ and $Se$.

Molecule

Chemical particles composed of two or more atoms united by a chemical bond.

Compound

Molecules composed of two or more different elements.

Kinetic energy

Energy in motion, which includes forms such as chemical, radiant, electrical, and mechanical energy.

Potential energy

Energy that is stored and has the potential to do work.

Catabolism

The sum of all decomposition reactions in the body, which are generally exergonic and release energy.

Anabolism

The sum of all synthesis reactions in the body, which are generally endergonic and require energy input.

Exergonic

Chemical reactions in which energy is released, such as in catabolic processes.

Endergonic

Chemical reactions in which energy is supplied or required, such as in anabolic processes.

Ionic bonds

Strong attractions between anions and cations that involve the transfer of electrons from one atom to another.

Covalent bonds

Chemical bonds formed by the sharing of one or more pairs of electrons between atoms.

Hydrogen bonds

A weak attraction between a slightly positive hydrogen atom in one molecule and a slightly negative oxygen or nitrogen atom in another.

Decomposition reaction

A reaction where a large molecule breaks down into two or more smaller ones, represented as $AB \rightarrow A + B$.

Synthesis reaction

A reaction where two or more small molecules combine to form a larger one, represented as $A + B \rightarrow AB$.

Exchange reaction

A reaction in which two molecules exchange atoms or groups of atoms, represented as $AB + CD \rightarrow AC + BD$.

Reversible reaction

A reaction that can proceed in either direction under different circumstances, such as the reaction between $CO_2$ and $H_2O$.

Catalysts

Substances such as enzymes that accelerate reaction rates by lowering the activation energy.

pH

A measure of acidity or basicity derived from the molarity of $H^+$ and calculated as $-\text{log} [H^+]$.

Buffer

A chemical or solution that resists changes in pH.

Adhesion

The tendency of one substance to cling to another substance.

Cohesion

The tendency of molecules of the same substance to cling to each other.

Carbohydrates

Organic compounds containing carbon, hydrogen, and oxygen, including sugars and starches.

Monosaccharides

Simple sugars with the general formula $C_6H_{12}O_6$, including isomers like glucose, galactose, and fructose.

Isomers

Molecules with the same molecular formula but different structural arrangements.

Disaccharides

Sugars composed of two monosaccharides, such as sucrose, lactose, and maltose.

Polysaccharides

Complex carbohydrates consisting of long chains of monosaccharides.

Lipids

Hydrophobic organic molecules including fatty acids, triglycerides, phospholipids, and steroids.

Triglycerides

Neutral fats composed of a single glycerol molecule and three fatty acid chains.

Phospholipids

Amphiphilic molecules consisting of a polar phosphorus-containing 'head' and two nonpolar fatty acid 'tails'.

Amphiphilic

A molecule that possesses both hydrophobic and hydrophilic regions.

Steroids

A category of lipids defined by a carbon skeleton with four fused rings, such as cholesterol.

Amino acid

The building blocks of proteins, consisting of an amino group ($NH_2$), a carboxy group ($COOH$), and a unique functional R group.

Primary structure

The sequence of amino acids joined together by peptide bonds.

Secondary structure

The alpha helix or beta sheet shape formed by hydrogen bonding in a protein.

Tertiary structure

The further folding and coiling of a protein due to interactions among R groups.

Quaternary structure

The association of two or more polypeptide chains with each other.

Protein Denaturation

A drastic conformational change in a protein that destroys its function and renders it unable to bind substrates.

Enzymes

Biological catalysts, usually named with the suffix '-ase', that speed up chemical reactions.

Substrate

The specific molecule that binds to the active site of an enzyme to undergo a chemical reaction.

ATP (Adenosine triphosphate)

A high-energy nucleotide composed of adenine, ribose, and three phosphate groups used to transfer energy within cells.

DNA (Deoxyribonucleic acid)

The double-stranded nucleic acid that contains the genetic material of the cell.

RNA (Ribonucleic acid)

A single-stranded nucleic acid containing ribose sugar and the base uracil instead of thymine.