Microbiology Unit 1 Overview: Key Concepts and Terms

Pathogen

Disease causing microbes

Parasite

Lives on or in the body of another organism called the host and causes damage to the host.

Commensal

Provides benefit to one party and neither harm nor benefit to the other.

Symbiont

Provides benefit to both parties.

Heterotroph

Relies on consuming other organisms, cannot synthesize its own sources of food.

Bacteria

Unicellular, prokaryotic microorganisms that can be found virtually everywhere.

Fungus

Eukaryotic organism that can be unicellular (yeasts) or multicellular (molds, mushrooms) and decomposes organic material.

Virus

Acellular entities made of RNA or DNA enclosed in a protein coat that require a host.

Protozoa

Eukaryotic, unicellular organisms that are mobile, live in water, and are disease causing.

Helminths

Eukaryotic, multicellular worms.

Binomial nomenclature

The correct method of writing scientific names of organisms, which should be underlined.

Normal microbiota

Microorganisms that should be found in the skin, GI tract, mouth, respiratory tract, and outer reproductive organs.

Beneficial functions of microorganisms

Food Production, Biotechnology & Genetic Engineering, Bioremediation, Nutrient Cycling.

Louis Pasteur

Conducted an experiment using Swan Neck flasks to show that bacteria does not just appear from thin air.

Koch's Postulates

1. Causative agent must be found in every case and absent from healthy hosts. 2. Agent must be isolated and grown outside host. 3. When agent is introduced to healthy host, the host gets sick.

Van Leeuwenhoek

Improved the microscope lens and was the first to observe and describe bacteria, protozoa, sperm cells, and red blood cells.

Germ Theory of Disease

The theory that microbes cause disease and spoilage and fermentation.

Pasteurization

Technique invented by Pasteur to kill harmful bacteria in food and drink.

Nutrient Cycling

The process involving decomposers that recycle nutrients in the environment.

Bioremediation

Using organisms to remedy an environmental problem, such as oil spills.

Gram

Developed Gram Stain

Gram-Positive stain

Purple

Gram-negative stain

Pink

Semmelweis

Handwashing to help prevent Puerperal fever

Lister

Antiseptic techniques

Handwashing before surgeries

A practice to reduce infection rates

Disinfecting surgical wounds with carbolic acid

Reduced mortality rates from surgical infections from 45% to 15% in 4 years

Nightingale and Nursing

Introduced idea of cleaning hospitals, bedding, and patients

Jenner

Edward Jenner's Vaccine

Cowpox

Used to prevent deadly smallpox

Immunology

Launched field of immunology and vaccination

Atoms

The smallest chemical units of matter

Nucleus

Structure containing protons and neutrons

Neutrons

Uncharged particles

Protons

Positively charged particles

Electrons

Negatively charged particles circling the nucleus

Valence electrons

Electrons in the outermost shell that interact with other atoms to form chemical bonds

Chemical Bonds

Form when atoms share or transfer valence electrons

Covalent Bond

Sharing a pair of electrons by two atoms (very strong bond)

Nonpolar Covalent Bond

Shared electrons spend an equal amount of time around each nucleus

Polar Covalent Bond

Unequal sharing of electrons due to different electronegative (pull on the electrons)

Ionic Bond

Occurs when 2 atoms with different electronegative come together and transfer electrons

Hydrogen Bonds

Weak forces that occur with polar covalent bonds

Metabolism

The sum of all chemical reactions in an organism

Anabolic

Involve the formation of larger, more complex molecules

Endothermic

Requires an input of energy

Dehydration Synthesis

Removal of -OH from one molecule and -H from another to form a new bond, producing water as a byproduct

Decomposition Reactions

Break bonds within larger molecules by adding water to form smaller substances.

Hydrolysis

A catabolic reaction that involves breaking down larger molecules by adding water.

Exothermic

Reactions that release energy.

Cellular Respiration

The process of breaking down substances to make ATP.

Digestion

The process of breaking down food into smaller components.

Fat Breakdown

The process of decomposing fats into smaller molecules.

Water

A substance with special characteristics that are critically important in living organisms.

Polar Covalent Bonds

Bonds that involve the unequal sharing of electrons between atoms.

Hydrogen Bonds

Weak attractions between a hydrogen atom and an electronegative atom.

Cohesive Molecules

Molecules that give strong surface tension due to their cohesive properties.

Solvent

A substance that can dissolve other substances due to its polarity.

pH

The negative log of hydrogen ions; a measure of acidity or alkalinity.

Acid

Substances that release H+ (hydrogen ions) and one or more anion when dissolved in water.

Base

Substances that bind to H+ when dissolved in water; some release cations and OH- (hydroxide ions).

Buffers

Solutions that resist pH level changes when small amounts of acid or base are added.

Functional Groups

Groups of atoms that contain carbon, hydrogen, and sometimes nitrogen and sulfur, contributing to the chemical properties of organic molecules.

Hydroxyl Group

A functional group (-OH) that increases solubility in water, found in ethanol and sugars.

Carbonyl Group

A functional group (-C=O) where a carbon atom is double bonded to an oxygen atom, found in acetone and formaldehyde.

Carboxyl Group

A functional group (-COOH) that acts as an acid by donating H+, found in acetic acid (vinegar).

Amino Group

A functional group (-NH2) that acts as a base, essential to the structure of amino acids and proteins.

Sulfhydryl Group

A functional group (-SH) that helps to stabilize protein structure, found in cysteine.

Phosphate Group

A functional group (-PO4^3-) that contributes to energy transfer in cells, found in ATP.

Methyl Group

A functional group (-CH3) that affects gene expression, found in methylated DNA.

Macromolecules

Large molecules made up of smaller units called monomers, essential for biological functions.

Macromolecules

Polymers made from monomers.

Monomers

The basic building blocks of macromolecules.

Carbohydrates

Composed of carbon, hydrogen, and oxygen.

Monosaccharides

Simple sugars such as glucose and fructose.

Disaccharides

Sugars composed of two monosaccharides, like sucrose and lactose.

Polysaccharides

Complex carbohydrates such as starch, cellulose, and chitin.

Energy sources

Primary function of carbohydrates.

Proteins

Composed of carbon, hydrogen, oxygen, nitrogen, phosphorus, and sulfur (CHONPS).

Amino Acids

Building blocks of proteins, containing a central carbon, amino group, carboxyl group, hydrogen atom, and R group.

Enzyme Catalysis

The process by which enzymes speed up chemical reactions, exemplified by lactase.

Lipids

Hydrophobic molecules primarily made of carbon and hydrogen.

Glycerol

A component of lipids.

Fatty Acids

Building blocks of lipids.

Triglycerides

A type of lipid formed from glycerol and fatty acids.

Saturated fat

A fat with no double bonds between carbon atoms.

Unsaturated fat

A fat with one or more double bonds between carbon atoms.

Nucleic Acids

Biopolymers essential for all known forms of life, composed of nucleotides.

Nucleotides

Building blocks of nucleic acids, consisting of phosphate, sugar, and nitrogenous bases.

DNA

Deoxyribonucleic acid, a molecule that carries genetic instructions.

RNA

Ribonucleic acid, involved in protein synthesis.

ATP

A nucleotide that serves as a short-term, recyclable energy supply for cells.

Peptide Bond

The bond formed between amino acids in proteins.

Glycosidic Bond

The bond formed between monosaccharides in carbohydrates.

Ester Bond

The bond formed between glycerol and fatty acids in lipids.

Phosphodiester Bond

The bond that links nucleotides in nucleic acids.

Unsaturated Fatty Acids

One or more double bond.

Saturated Fat

NO double bond.

Phospholipid

Molecule with a hydrophilic head (polar) and a hydrophobic tail (non-polar), making it amphipathic.

Hydrophilic Head

Part of a phospholipid that is attracted to water, consisting of a nitrogen group, phosphate group, and glycerol.