Chapter 1 and 2 Microbiology and Chemistry of Biology Vocabulary

75 vocabulary flashcards covering key terms from Chapter 1: Introduction and History of Microbiology and Chapter 2: Chemistry of Biology.

Microorganism, microbe

An organism or microscopic agent too small to be seen clearly with the naked eye, including bacteria, fungi, protozoa, algae, and viruses.

Fungi

Eukaryotic organisms, including molds and yeasts, that acquire nutrients from other organisms and possess cell walls.

Protozoa

Single-celled eukaryotic microorganisms that are typically motile and lack cell walls.

Algae

Photosynthetic eukaryotic organisms that possess cell walls and can be unicellular or multicellular.

Bacteria

Single-celled prokaryotic microorganisms that usually possess cell walls containing peptidoglycan and lack a membrane-bound nucleus.

Archaea

Single-celled prokaryotic microorganisms that lack peptidoglycan in their cell walls and often inhabit extreme environments.

Viruses

Acellular infectious agents composed of nucleic acid surrounded by a protein coat that require a host cell to replicate.

Prokaryotes

Microorganisms that lack a membrane-bound nucleus and other membrane-bound cellular organelles.

Eukaryotes

Organisms whose cells contain a membrane-bound nucleus and other membrane-bound cellular organelles.

Parasitic worms

Multicellular eukaryotic parasites, also known as helminthes, that cause diseases in host organisms.

Spontaneous generation

The historical hypothesis that living organisms can arise spontaneously from nonliving matter.

Scientific method

A systematic framework for scientific inquiry involving observation, hypothesis generation, experimentation, and analysis.

Fermentation

The enzymatic breakdown of carbohydrates by microorganisms in the absence of oxygen to produce alcohol, organic acids, or gases.

Germ theory of disease

The principle that specific microorganisms are the primary cause of specific infectious diseases.

Pathogen

Any microorganism or biological agent capable of causing disease in a host organism.

Koch’s postulates

A series of four experimental criteria used to demonstrate that a specific microorganism causes a specific disease.

Gram stain

A differential staining technique used to classify bacteria into Gram-positive or Gram-negative based on cell wall composition.

Nosocomial infections

Infections acquired by a patient during treatment or care within a hospital or healthcare facility.

Immunology

The branch of science that studies the body's immune system and its defenses against pathogens.

Chemotherapy

The treatment of disease using chemical substances or antimicrobial drugs.

Electron

A negatively charged subatomic particle that orbits the nucleus of an atom.

Proton

A positively charged subatomic particle located within the nucleus of an atom.

Neutron

An uncharged (neutral) subatomic particle located within the nucleus of an atom.

Atom

The smallest unit of a chemical element that retains the chemical properties of that element.

Nucleus (of an atom)

The central core region of an atom containing its protons and neutrons.

Molecule

A chemical structure consisting of two or more atoms bound together by chemical bonds.

Electron shell

A region surrounding an atomic nucleus where electrons orbit in energy levels.

Valence shell

The outermost electron shell of an atom, which determines its chemical reactivity and bonding capacity.

Compound

A substance formed when atoms of two or more different elements combine chemically in fixed ratios.

Chemical bond

An attractive force between atoms that holds them together to form molecules or compounds.

Nonpolar covalent bond

A covalent bond formed when two atoms share electrons equally due to similar electronegativities.

Polar covalent bond

A covalent bond formed when two atoms share electrons unequally, resulting in partial positive and negative charges.

Ionic bond

A chemical bond formed by electrostatic attraction between oppositely charged ions following electron transfer.

Electronegativity

A measure of the relative attraction an atom has for shared electrons in a chemical bond.

Ion

An atom or group of atoms that has acquired a net electrical charge by gaining or losing one or more electrons.

Cation

A positively charged ion formed when an atom loses one or more electrons.

Anion

A negatively charged ion formed when an atom gains one or more electrons.

Hydrogen bond

A weak attraction between a partially positive hydrogen atom in one polar molecule and an electronegative atom in another.

Chemical reaction

A process involving the breaking and forming of chemical bonds to transform reactant substances into product substances.

Reactant

A starting substance that undergoes change during a chemical reaction.

Product

A substance produced as a result of a chemical reaction.

Polar molecule

A molecule containing an unequal distribution of electrical charge, resulting in distinct positive and negative poles.

Nonpolar molecule

A molecule possessing equal charge distribution without distinct positive or negative electrical poles.

Hydrophilic

Describing substances that have an affinity for water and readily interact with or dissolve in polar solvents.

Hydrophobic

Describing nonpolar substances that lack an affinity for water and do not dissolve in aqueous solutions.

Functional group

A specific arrangement of atoms within an organic molecule that confers characteristic chemical properties and reactions.

Hydroxyl group

A functional group consisting of a hydrogen atom bonded to an oxygen atom ($\text{-OH}$).

Amino group

A functional group consisting of a nitrogen atom bonded to two hydrogen atoms ($\text{-NH}_2$).

Carboxyl group

A functional group consisting of a carbon double-bonded to an oxygen and single-bonded to a hydroxyl group ($\text{-COOH}$).

Phosphate group

A functional group consisting of a phosphorus atom bonded to four oxygen atoms ($\text{-PO}_4^{3-}$).

Acid

A substance that dissociates in water to yield hydrogen ions ($\text{H}^+$), decreasing the solution's $\text{pH}$.

Base

A substance that accepts hydrogen ions or yields hydroxide ions ($\text{OH}^-$) in water, increasing the solution's $\text{pH}$.

pH

A logarithmic measurement of the concentration of hydrogen ions ($\text{H}^+$) in a solution, indicating acidity or alkalinity.

Endothermic

Describing a chemical reaction or physical process that absorbs thermal energy from its surroundings.

Exothermic

Describing a chemical reaction or physical process that releases thermal energy into its surroundings.

Monomer

A small molecular subunit that can bind to other similar subunits to build a larger polymer.

Polymer

A large molecule composed of many repeating monomer subunits joined together by chemical bonds.

Dehydration synthesis

A chemical reaction that joins monomer molecules together with the removal of a water molecule.

Hydrolysis

A chemical reaction that breaks covalent bonds in polymers by the addition of a water molecule.

Lipid

A diverse class of hydrophobic organic molecules, including fats, phospholipids, and steroids.

Fatty acid

A hydrocarbon chain terminating in a carboxyl group ($\text{-COOH}$) that serves as a building block for lipids.

Steroid

A lipid molecule characterized by a carbon skeleton composed of four fused rings.

Phospholipid

A lipid composed of glycerol bonded to two fatty acid tails and a polar phosphate head group, forming cellular membranes.

Carbohydrate

An organic compound composed of carbon, hydrogen, and oxygen atoms, serving as a primary energy source and structural component.

Monosaccharide

The simplest form of carbohydrate, consisting of a single sugar monomer such as glucose.

Disaccharide

A carbohydrate composed of two monosaccharide units linked by a covalent glycosidic bond.

Polysaccharide

A complex carbohydrate polymer consisting of many monosaccharide units linked together.

Protein

A biological macromolecule composed of one or more polypeptide chains folded into a specific three-dimensional structure.

Amino acid

An organic monomer containing an amino group ($\text{-NH}_2$), a carboxyl group ($\text{-COOH}$), and a distinct side chain, acting as a protein subunit.

Peptide bond

The covalent bond formed between the carboxyl group of one amino acid and the amino group of another during protein synthesis.

Polypeptides

Unbranched linear chains of amino acids linked together by peptide bonds.

Denaturation

A process in which a protein loses its native three-dimensional shape and biological activity due to external factors like heat or extreme $\text{pH}$.

Deoxyribonucleic acid

A double-stranded nucleic acid molecule (DNA) that stores the genetic code for cellular life.

Ribonucleic acid

A nucleic acid molecule (RNA) involved in protein synthesis and genetic expression, typically single-stranded.

Nucleotide and Adenosine triphosphate

A nucleotide is the monomer subunit of nucleic acids consisting of a sugar, phosphate, and nitrogenous base; Adenosine triphosphate (ATP) is a key nucleotide used for cellular energy storage and transfer.