Microbiology Lecture Notes Review

Flashcards covering key vocabulary, concepts, and milestones from the lecture notes on microbiology, including microbial groups, roles, organic compounds, cell structures, virus characteristics, and microbial growth.

Microbe (Microorganism)

An organism that is too small to be seen with the unaided eye, requiring a microscope.

Bacteria

One of the four major microbe groups, studied in bacteriology. Examples include E.coli and Salmonella.

Viruses

One of the four major microbe groups, studied in virology. Examples include coronavirus, herpes, and HIV.

Fungi

One of the four major microbe groups, studied in mycology. Examples include mold and yeast.

Parasites

One of the four major microbe groups, studied in parasitology. Examples include protozoan parasites and worms.

Decomposers of organic wastes

A key ecological role of bacteria and fungi that breaks down wastes and recycles elements.

Photosynthesis (Microbial)

A process carried out by bacteria (Cyanobacteria) and protozoa (Algae) that produces oxygen.

Nitrogen Fixation

A process by bacteria that converts free atmospheric Nitrogen (N2) into nitrates, which are useful for plant development.

Bioremediation

The artificial use of microbes to remove toxic substances from the environment, often by certain bacteria using pollutants as an energy source.

Antibiotics

Substances produced by some microbes (e.g., Penicillin from fungal mold) that destroy harmful bacteria.

Pathogenic Microbes (Pathogens)

Harmful living agents capable of causing disease in a host.

Normal Microbiota (Normal Flora)

Resident microbes found inside and outside the human body that typically cause no harm, play roles in human health, and prevent disease.

Van Leeuwenhoek

Considered the father of microbiology for being the first scientist to observe and make detailed drawings of live microorganisms.

Jenner

Considered the father of vaccines; developed the first vaccine (against smallpox) based on observations of cowpox protecting against smallpox.

Spontaneous Generation

The discredited theory that non-living things can give rise to living things.

Theory of Biogenesis

Established by Pasteur, stating that living cells arise only from pre-existing living cells.

Germ Theory of Disease

Supported by Robert Koch, stating that microorganisms (pathogens) cause disease.

Pasteur

Scientist who disproved spontaneous generation and established the theory of biogenesis using his S-shaped flask experiments.

Lister

A surgeon who applied the Germ Theory to medical procedures, using chemical solutions (antiseptics) to reduce surgical infections and deaths.

Koch

Established the 'Germ Theory,' discoverer of Bacillus anthracis as the cause of Anthrax, and created Koch's Postulates.

Koch's Postulates

A set of experimental steps used to relate a specific microbe to a specific disease and its symptoms.

Ehrlich

Developed the concept of chemotherapy, discovering the first chemical substance against syphilis, and coined the term 'magic bullet'.

Magic Bullet

A chemical substance designed to selectively target and destroy a pathogen without harming the infected host.

Fleming

Discovered the first antibiotic, penicillin, from a fungal mold, observing its ability to inhibit bacterial growth.

Marshall

Proved that most peptic ulcers were caused by the bacterium H. pylori, establishing a link to gastric cancer.

Emerging Infectious Diseases (EIDs)

Diseases that are new or changing and are increasing (or have the potential to increase) in frequency in the near future.

Inorganic Compounds

Small, simple molecules that usually lack carbon, such as H2O, O2, and salts.

Organic Compounds

Large, structurally complex molecules that always contain carbon and are held together by covalent bonds.

Functional Groups

Groups of atoms that can bind to the carbon skeleton of organic compounds, determining their properties.

Dehydration Synthesis

A process where several small monomers combine to form one large polymer by losing a water molecule, forming covalent bonds.

Hydrolysis

A process where one large polymer breaks down into several small monomers by adding a water molecule, breaking covalent bonds.

Carbohydrates (Carbs or Sugars)

Organic compounds composed of carbon, hydrogen, and oxygen, usually ending in '-ose'.

Monosaccharides

Simple sugars (3-7 carbon atoms) that provide a quick source of energy for living cells. Examples include Glucose and Fructose.

Disaccharides

Formed when two monosaccharides link via a glycosidic bond, providing structural components. Examples include Sucrose and Lactose.

Polysaccharides

Consist of many monosaccharides joined together, functioning as long-term energy sources and structural components. Examples include Starch, Glycogen, and Cellulose.

Proteins

Essential organic compounds composed of amino acids, vital for cell structure and function, and are the most diverse organic compounds.

Structural Proteins

Proteins like keratin that reinforce skin, acting as a physical barrier to infection.

Transporter Proteins

Proteins in cell membranes (e.g., channels, carriers) involved in facilitating movement across membranes.

Enzymes

Proteins that speed up chemical reactions.

Antibodies

Proteins involved in the immune response.

Amino Acids

The building blocks (subunits) of proteins, characterized by a central carbon, amino group, carboxyl group, hydrogen, and a variable side group (R group).

Peptide Bonds

Covalent bonds linking two amino acids together via dehydration synthesis.

Protein Denaturation

The process where a protein loses or changes its shape (structure) and thus its function, often due to harsh environments like high temperature or low pH.

Primary Protein Structure

A linear sequence of amino acids, forming a polypeptide chain.

Secondary Protein Structure

Occurs when the amino acid chain folds and coils into a helix or pleated sheet due to hydrogen bonds.

Tertiary Protein Structure

Occurs when the helix or pleated sheet folds irregularly into a 3D shape, involving disulfide bridges, hydrogen bonds, and ionic bonds.

Quaternary Protein Structure

Consists of two or more polypeptide chains (tertiary subunits) bound to each other, forming a bulky and complex protein, such as hemoglobin or antibodies.

Lipids

Organic compounds characterized by carbons, hydrogens, and oxygen; primary components of cell membranes.

Triglycerides

Subunits (building blocks) of simple lipids, containing one glycerol and three fatty acid chains linked by ester bonds.

Saturated Fatty Acids

Fatty acids that contain no double bonds, only single bonds.

Unsaturated Fatty Acids

Fatty acids that contain one or more double bonds.

Phospholipids

Complex lipids with polar heads and nonpolar fatty acid tails, forming the phospholipid bilayer of cell membranes and regulating transport.

Steroids and Sterols

Lipids formed from three 6-carbon rings attached to one 5-carbon ring, with sterols specifically having an -OH group attached.

Cholesterol

A sterol found in animal cell membranes.

Nucleic Acids

Organic compounds composed of carbon, hydrogen, oxygen, and nitrogen, functioning in storing genetic information and protein synthesis.

Nucleotides

The subunits (building blocks) of nucleic acids, consisting of a 5-carbon pentose sugar, a phosphate group, and a nitrogen-containing base.

Purine

Nitrogen-containing bases including Adenine and Guanine, found in nucleic acids.

Pyrimidine

Nitrogen-containing bases including Cytosine, Uracil, and Thymine, found in nucleic acids.

DNA (Deoxyribonucleic Acid)

A double-stranded molecule (double helix) that stores genetic information, characterized by A-T and C-G pairing and containing Thymine.

RNA (Ribonucleic Acid)

Usually a single-stranded molecule involved in protein synthesis (mRNA, tRNA, rRNA), characterized by containing Uracil instead of Thymine.

ATP (Adenosine Triphosphate)

A high-energy nucleic acid (single nucleotide) where stored chemical energy is released by hydrolysis of bonds connecting its phosphate groups.

Monomorphic

Describes bacteria that maintain an identical shape, typical for the majority of bacterial species.

Pleomorphic

Describes bacteria that can exhibit several different shapes, indicating potential presence of more than one bacterial type.

Coccus

A basic spherical or round shape for bacteria.

Bacillus

A basic rod-shaped form for bacteria.

Spiral (Bacteria Shape)

A general category for motile bacteria including Vibrio, Spirillum, and Spirochetes.

Vibrio

A comma-shaped or bent spiral bacterium.

Spirillum/Spirilla

Rigid, short/thick, loosely-coiled spiral bacteria that move via external flagella.

Spirochetes

Flexible, longer/thin, tightly-coiled spiral bacteria that move via internal endoflagella.

Diplo-

A prefix indicating bacteria arranged in pairs (e.g., diplococci, diplobacilli).

Staphylo-

A prefix indicating bacteria arranged in clusters (e.g., staphylococci).

Strepto-

A prefix indicating bacteria arranged in chains (e.g., streptococci, streptobacilli).

Glycocalyx

An optional, viscous, and gelatinous layer external to the cell wall of some bacteria, made of polysaccharide or polypeptide.

Capsule

A thick, organized, and tightly attached type of glycocalyx, often made of polysaccharide, aiding bacterial attachment and escape from phagocytosis.

Slime Layer

A thin, unorganized, and loosely attached type of glycocalyx, typically made of protein.

Flagellum

A structure composed of a filament, hook, and basal body, used by some bacteria for motility.

Axial Filament (Endoflagella)

An internal structure found in Spirochetes, anchored at one end, made of proteins, whose rotation causes a corkscrew-like cell movement.

Fimbriae

Hair-like protein appendages external to the cell that allow for attachment to surfaces.

Pili

Protein appendages external to the cell involved in 'twitching' motility and DNA transfer between cells (e.g., conjugation pilus).

Cell Wall (Prokaryotic)

The outermost layer of most bacteria, preventing osmotic lysis, protecting the cell membrane, and containing peptidoglycan.

Peptidoglycan

A primary component of bacterial cell walls, consisting of rows of carbohydrates connected to proteins, varying in amount between different bacterial types.

Gram-Positive Bacteria

Bacteria characterized by a thick peptidoglycan layer in their cell walls, which stains purple with Gram stain.

Gram-Negative Bacteria

Bacteria characterized by a thin peptidoglycan layer in their cell walls and an outer membrane, which stains red/pink with Gram stain.

Lipo-poly-saccharide (LPS)

A complex molecule found in the outer membrane of Gram-negative cell walls, containing Lipid A (a toxin) and O polysaccharide (an antigen).

Lipid A

A component of LPS embedded in the outer membrane of Gram-negative cell walls, functioning as a toxin.

O Polysaccharide

A component of LPS that sticks out from the Gram-negative cell wall's outer membrane, acting as a surface marker or antigen.

Teichoic Acids

Polymers found only in Gram-positive cell walls that attract ions to strengthen the cell wall and add rigidity.

Gram Staining

A differential staining method used to classify and identify bacteria based on their cell wall differences, resulting in purple for Gram-positive and red/pink for Gram-negative.

Mycobacterium (Cell Wall)

A genus of bacteria that possesses an extra waxy lipid, mycolic acid, bound to peptidoglycan in its cell wall, making it resistant to digestion by phagocytosis.

Mycolic Acid

A waxy lipid material present in the cell wall of Mycobacterium tuberculosis, preventing its digestion by phagocytes.

Mycoplasma (Cell Wall)

A genus of bacteria that lacks cell walls.

Domain Archaea (Cell Wall)

Prokaryotic organisms whose cell walls do not contain peptidoglycan.

Plasma (Cell) Membrane (Prokaryotic)

A phospholipid bilayer deep to the cell wall that encloses the cytoplasm, selectively permeable, and the site of ATP production and photosynthesis in bacteria.

Selective Permeability

The property of the cell membrane that allows the passage of some molecules but not others, regulating what enters and leaves the cell.

Passive Transport

The movement of particles from an area of high to low concentration without requiring cellular energy.

Simple Diffusion

Passive transport involving the movement of small, uncharged particles directly across the cell membrane.

Facilitated Diffusion

Passive transport of large, charged particles that requires a protein channel or carrier.

Osmosis

Passive transport involving the movement of water across a membrane, moving towards an area of higher particle concentration.

Isotonic Solution

A solution where the concentration of particles is the same inside and outside the cell, resulting in no net water movement.

Hypotonic Solution

A solution with a lower particle concentration than inside the cell, causing the cell to swell as water enters.