Microbiology: Chemical Principles

Flashcards for Microbiology Lecture Review

Chemistry

The study of interactions between atoms and molecules.

Atom

The smallest unit of matter that cannot be subdivided without losing its properties.

Electrons, Protons, Neutrons

Subatomic particles that compose atoms.

Chemical Element

Atoms with the same number of protons.

Most Abundant Chemical Elements in Living Organisms

Hydrogen, Carbon, Nitrogen, Oxygen

Chemical Bonds

Attractive forces between atoms due to valence electrons.

Molecule

Group of two or more atoms held together by chemical bonds.

Compound

A molecule containing two or more kinds of atoms.

Ions

Charged atoms that have gained or lost electrons.

Cations

Ions with a positive charge.

Anions

Ions with a negative charge.

Ionic Bonds

Attractions between ions of opposite charge.

Covalent Bonds

Bonds formed when two atoms share one or more pairs of electrons.

Hydrogen Bonds

Bonds formed when a hydrogen atom covalently bonded to an O or N atom is attracted to another N or O atom.

Chemical Reactions

Involve the making or breaking of bonds between atoms

Synthesis Reactions

Atoms, ions, or molecules combine to form new, larger molecules.

Anabolism

The synthesis of molecules in a cell.

Decomposition Reactions

A molecule is split into smaller molecules, ions, or atoms.

Catabolism

Decomposition reactions in a cell.

Exchange Reactions

Reactions that are part synthesis and part decomposition.

Organic Compounds

Compounds that always contain carbon and hydrogen.

Inorganic Compounds

Compounds that typically lack carbon-hydrogen bonds.

Polar Molecule

Unequal distribution of charges in a molecule.

Acids

Substances that dissociate into one or more hydrogen ions and one or more negative ions.

Bases

Substances that dissociate into one or more hydroxide ions and one or more positive ions.

Salts

Substances that dissociate into cations and anions, neither of which is H+ or OH-

pH

The concentration of H+ in solution.

Carbon Skeleton

The chain of carbon atoms in an organic molecule.

Functional Groups

Responsible for most of the chemical properties of a particular organic compound.

Macromolecules

Large polymers consisting of many small repeating molecules called monomers.

Carbohydrates

Serve as cell structures and cellular energy sources, including sugars and starches.

Proteins

Essential in cell structure and function, including enzymes, transporter proteins, and structural components.

Amino Acids

Subunits (monomers) that make up proteins

Denaturation

Occurs when proteins encounter hostile environments and lose their shapes and functions.

Nucleic Acids

Carry genetic information and include DNA and RNA.

Nucleotides

Building blocks of nucleic acids, consist of a pentose sugar, phosphate group, and nitrogen-containing base.

DNA (Deoxyribonucleic Acid)

Contains deoxyribose, exists as a double helix, stores genetic instructions.

RNA (Ribonucleic Acid)

Contains ribose, is single-stranded.

Adenosine Triphosphate (ATP)

Principle energy-carrying molecule of all cells.

Lipids

Nonpolar molecules insoluble in water, function as structural components and energy storage.

Simple Lipids

Fats or triglycerides, contain glycerol and fatty acids.

Complex Lipids

Include phospholipids and steroids, cell membranes are made of phospholipids.

Steroids

Four carbon rings with an -OH group attached to one ring.