Ch 1-10

Flashcards on core microbiology topics including historical foundations, taxonomy, cell transport, prokaryotes vs eukaryotes, DNA replication, enzymes, and microbial control.

Louis Pasteur

A key scientist ($1822\text{--}1895$) who helped found microbiology, disproved spontaneous generation using S-shaped flasks, and developed pasteurization and modern aseptic techniques.

Carolus Linnaeus

Scientist who established the basic naming and classification system for living organisms in $1735$, designing the binomial nomenclature system.

Biogenesis

The hypothesis that living cells arise only from preexisting living cells.

Pasteurization

A heat treatment method developed by Louis Pasteur to destroy microorganisms responsible for food spoilage.

Binomial Nomenclature

A naming system created in $1735$ where every organism is given a two-part latinized name consisting of its capitalized genus and uncapitalized specific epithet.

Taxonomy

The science of classifying organisms and establishing relationships among them.

Robert Koch

Microbiologist ($1843\text{--}1910$) who proved in $1876$ that bacteria cause disease using Bacillus anthracis and formulated Koch's postulates.

Koch's Postulates

A set of experimental steps used to link a specific pathogen to a specific disease, such as anthrax or tuberculosis.

Carl Woese

Microbiologist who in $1978$ proposed the three-domain classification system based on cellular organization and ribosomal RNA phylogeny.

Joseph Lister

Surgeon who introduced aseptic medical techniques in the $1860\text{s}$, using phenol (carbolic acid) and chloride of lime to prevent surgical infections.

Domain Bacteria

A domain of prokaryotic organisms whose cell walls contain peptidoglycan.

Domain Archaea

A domain of prokaryotic organisms whose cell walls lack peptidoglycan, often including methanogens and extremophiles.

Domain Eukarya

A domain comprising organisms composed of eukaryotic cells, including protists, fungi, plants, and animals.

Prokaryote

An organism lacking a nucleus or membrane-enclosed organelles, usually containing a single circular chromosome, typically $0.2\,\text{--}\,2.0\,\mu\text{m}$ in diameter, and dividing by binary fission.

Eukaryote

An organism whose cells contain a distinct membrane-bound nucleus, histones, membrane-enclosed organelles, and are typically $10\text{--}100\,\mu\text{m}$ in diameter.

Isotonic Solution

A solution where solute concentration outside the cell equals that inside, resulting in zero net water movement and stable cell volume.

Hypotonic Solution

A solution with a lower solute concentration outside the cell than inside, causing water to enter the cell and potentially causing osmotic lysis.

Hypertonic Solution

A solution with a higher solute concentration outside the cell than inside, causing water to move out of the cell and leading to plasmolysis.

Osmotic Lysis

The bursting of a cell due to excess water influx in a hypotonic environment when the cell wall is weak or damaged.

Plasmolysis

The shrinking of a cell's cytoplasm away from its cell wall when placed in a hypertonic environment.

Passive Transport

The movement of substances across a plasma membrane down their concentration gradient without cellular energy consumption.

Simple Diffusion

The passive movement of molecules or ions directly through the lipid bilayer from high to low concentration until equilibrium is reached.

Facilitated Diffusion

Passive movement of substances across a membrane from high to low concentration using specific carriers or nonspecific channel transporter proteins.

Osmosis

The diffusion of water molecules across a selectively permeable membrane through the lipid bilayer or specialized aquaporin channels.

Active Transport

Energy-requiring movement of substances across a membrane against their concentration gradient (low to high) via transporter proteins.

Group Translocation

A form of active transport in prokaryotes where a substance is chemically modified (e.g., phosphorylated) during transport, trapping it inside the cell.

Origin of Replication

The specific sequence or site on a DNA molecule where DNA replication begins.

Replication Fork

The Y-shaped region where parent DNA strands are opened up and new strands are synthesized during DNA replication.

Leading Strand

The newly synthesized DNA strand built continuously in the $5' \rightarrow 3'$ direction towards the replication fork.

Lagging Strand

The newly synthesized DNA strand constructed discontinuously in short pieces away from the replication fork.

Okazaki Fragments

Short segments of DNA synthesized on the lagging strand during DNA replication.

DNA Polymerase

The enzyme responsible for adding new DNA nucleotides exclusively to the $3'$ end of a growing DNA strand.

Active Site

The specific region on an enzyme where the substrate binds to form an enzyme-substrate complex.

Denaturation

The loss of an enzyme's functional three-dimensional structure due to adverse environmental factors like high heat or extreme pH.

Competitive Inhibition

Enzyme inhibition where an inhibitor directly competes with the substrate for binding to the active site.

Noncompetitive Inhibition

Enzyme inhibition where an inhibitor binds to an allosteric site other than the active site, changing the enzyme's shape and preventing proper activity.

Feedback Inhibition

A control process where the final end product of a metabolic pathway inhibits an enzyme operating early in that pathway.

Gene

A specific transcribable segment of DNA that encodes functional biological information for synthesizing a protein or an RNA.

Gene Expression

The complete process by which information stored in a gene is transcribed into mRNA and translated to manufacture a functional product like a protein.

Ionizing Radiation

High-energy radiation (such as X-rays and gamma rays) that ionizes cellular water, generating reactive hydroxyl radicals that destroy DNA backbones and kill microorganisms.

Mitochondria

Power house (produces ATP)

Ribosomes

Factory (builds proteins)

Nucleus

DNA/control center (the brain)

Golgi apparatus

Shipping center (post office)

Lysosomes

Organelles that act as the stomach and garbage disposal

Chloroplast

Photosynthesis (turns sunlight into food, present in plant and algal cells)

Cell membrane

Controls entry/exit (separates its inside contents from the outside environment)

Robert Hook

And 1665 reported that all things are composed of little “cells”

Rudolph Virchow

In 1858 stated that living cells arise from pre-existing cells (theory of biogenesis)

Edward Jenner

In 1796 gave a person cowpox that became immune to smallpox

Alexander Fleming

In 1928 he discovered the first antibiotic by accident. Noticed a penicillin fungus→ Produced penicillin (An antibiotic) → killed staphylococcus aureus. In 1940s it was tested on patients in mass as of medicine.

mycology

The study of fungi bacteriology parasitology. The way a gene expresses itself not the gene itself.

Molecular Biology

Studies how DNA carries genetic information

James Watson and Francis crick

In 1953 proposed a model of DNA structure

Francois jacob and Jacques Monod

In 1961 discovered mRNA in protein synthesis

Genome

All the genetic information in a cell

Genotype

The genetic makeup of an organism

Phenotype

Expression of genes

Amino acids

Are in a particular sequence, they are joined by peptide bond

Constitutive

Genes that are continuously being produced. example enzymes keratin, hemoglobin, and collagen

Repression

Minimizes gene expression

Induction

Turns on gene expression