BIO150: Content for Test 1

Introduction, Cell Biology, Factors Affecting Microbial Growth

Science

systematic way of asking questions and investigating them objectively, consistently, reproducibly, numerically, to best dispel ignorance

Dependent Variable (DV)

relates to observations/questions; what is measured/the data collected; effect

Independent Variable (IV)

relates to the hypothesis; what is being changed /tested by the scientist via manipulation; cause

Hypothesis

proposed, specific explanation to address the question

Microorganism

an organism of microscopic size, which may exist in its single-celled form or as a colony of cells; loosely defined as science evolves

Saphrophyes

heterotrophic organisms that obtain their nutrients by breaking down dead or decaying organic matter

Fungi

eukaryotic, best saprophytes in the five kingdoms; includes molds, mushrooms, yeasts

Filamentous Mold

type of fungi characterized by their thread-like structures known as hypha; able to extend filaments (tiny limbs) into decaying matter

Fruiting Body

a structure that houses the spores for reproduction in fungi

Venomous

property of an animal that bites or stings to cause harm

Poisonous

property of an animal that causes harm when ingested or touched

Metabolism

the mechanism by which living things processes its environment to create its vital energy

Genome

all of a living organism’s genetic material

Histones

structural proteins present in eukaryotic cells that help compact and organize DNA, analogous to a thread spool

Plasmids

extrachromosomal (not attached to the main chromosome) extra pieces of circular DNA floating about in the cytoplasm that replicate independently

Conjugation

transfer of plasmid DNA from one cell to another using a pilus

Pilus

physical structure that forms between two cells during conjugation to trade plasmids

Cilia

very small, finger-like projections that coat the outside of the cell; a Protozoan trait that works by beating in waves to move the cell

Amoeboid

a crawling-like type of locomotion used by cells and single-celled organisms that change their shape by pushing out temporary projections called pseudopodia

Fimbriae

short, hair-like protein appendages found on the surface of many bacteria that allow them to stick to surfaces, host cells, and other bacteria

Virulence

the ease at which an organism can cause disease; has several factors, like infectivity and severity

Infectivity

how easy it is to contract

Severity

how strong the disease is

Algae

members of a group of predominantly aquatic photosynthetic organisms, similar to plant life

Protozoa

microscopic acellular animalcules existing singly or in colonies, without tissue and organs, having one or more nuclei

Prokaryotes

organisms with cell walls made of peptidoglycan (made of peptides and polysaccharides, or proteins and sugar); has simple DNA that floats freely in the cytoplasm that contains no organelles

Archaea

genetically ancient unique among prokaryotes (very low mutation rates) and able to survive extreme environments

Cyanobacteria

bluish-greenish photosynthetic bacteria that share the same environment as algae

Micrometer (μm)

a unit of measurement for microscopic organisms 1,000 μm in a millimeter

Capsule/Glycocalix/Slime Layer

a layer of polysaccharides that envelopes the cell wall

Bio-Films

biological coating on a surface; build-up of organic matter

Cell Wall

a rigid yet porous layer outside the cell membrane that is composed of different materials depending on the type of cell; not present in animals and protozoa

Peptidoglycan

a component of bacterial cell walls that is composed of polysaccharides and tetrapeptide bridges; the “shingles” of the cell wall

Mycoplasma

a bacterial genus that lacks a cell wall

Endotoxic

characteristic of a cell that produces a toxin in which the toxin remains inside the cell as a component of the cell; the outer membrane itself is the toxin

Exotoxic

characteristic of a cell that produces a toxin in which the toxin exits the cell; can spread and cause issues in places where the cell is not present

Hypotonic Solution

the cell contains more solute than the solution

Plasmoptysis

explosion of the cells when the water rushes into the cell that inside a hypotonic solution

Hypertonic Solution

the cell contains less solute than the solution

Plasmolysis

shriveling of the cells when the water rushes out of a cell that is inside a hypertonic solution

Isotonic Solution

the solute concentration is the same across the cell and the solution

Bactericidal

characteristic of something to kill existing cells; includes substances that disrupt the cellular envelope (cell membrane and, if applicable, the cell wall)

Bacteriostatic

characteristic of something that prevents cells from dividing; includes substances that disrupt protein production/gene expression/ribosome activity

Broad Spectrum Drugs

able to kill a wide range of things; typically interferes with protein production/gene expression/ribosome activity

Narrow Spectrum Drugs

kills things with a narrow range of things by targeting specific characteristics; can prevent wiping out competition/the beneficial bacteria present; includes 𝛃 lactam

Gram-Positive Bacteria

has a thick cell wall with teichoic acids, vulnerable to 𝛃 lactam antibiotics (narrow spectrum)

Gram-Negative Bacteria

has a thin cell wall and an outer lipid layer (no teichoic acids), vulnerable to broad spectrum antibiotics

Histoplasma

a fungus (specifically, a mold) that causes histoplasmosis, a fungal infection of the lungs caused by inhalation of the spores

Candida

a fungus (specifically, a yeast) that the is most common cause of fungal infections (Candidiasis) worldwide and the largest genus of medically important yeasts

Entamoeba

a protist (specifically, a protozoa) that causes a parasitic infection when consumed from a contaminated water source; causes diarrhea

Mycobacterium tuberculosis

capsulated bacterial cell that causes tuberculosis, a disease so deadly because the immune system is fooled by its antiphagocytotic measures

Streptococcus salivarius

Gram-positive bacterial capsulated cell that causes the plaque on teeth and outcompetes other pathogens present in the mouth

Klebsiella pneumonia

bacteria (king of capsule protection) that generates more capsule than any other cell; also an opportunistic and antibiotic resistant

Neisseria gonorrhoeae

Gram-negative bacteria that uses fimbriae to attach to the urogenital epithelium

Borrellia

a group of spiral-shaped bacteria (spirochete) that cause serious illnesses like Lyme disease and relapsing fever

Paramecium

a genus of eukaryotic in the kingdom Protista, singe-celled organisms known for their cilia

Clostridium difficile (C. diff)

Gram positive obligate anaerobe bacteria that causes awful gastrointestinal issues (perforation, sepsis)

Plasmodium

protozoan that causes malaria

Salmonella

bacterial infection that can be transmitted via reptile vectors

Rhabdovirus

virus that causes rabies; some mammals are vectors while others become hosts

Eastern Equine Encephalitis (EEE) Virus

a virus that can be found in the avian reservoirs

Acid

proton donor; donates protons to substances that it is exposed to

Base

proton acceptor; soaks up protons from the substances that it is exposed to

Buffer

resist pH change by acting like acids (donating protons) and bases (accepting protons), depending on the environment

Bicarbonate (HCO3-) Buffer System

maintains blood pH within the normal range of 7.35 to 7.45 by neutralizing excess acids and bases through a reversible chemical equilibrium

Endospores

bacterial survival mechanism; tough, dormant, and non-reproductive structures that certain bacteria form inside

Sporulation

the multi-step process by which certain bacteria transform from a normal, active cell (vegetative cell) into a dormant, highly resistant structure called an endospore

Mesophiles

an organism that grows best in moderate temperatures, typically between 20°C and 45°C (68°F and 113°F)

Thermophiles

specialized microorganisms that thrive in hot environments, typically growing best at temperatures between 41°C and 80°C (106°F to 176°F)

Hyperthermophiles

survive above 80°C (176°F)

Obligate Aerobes

complete aerobic respiration; must have oxygen and tolerates it well

Microaerophiles

subgroups of aerobic respirators that require oxygen but cannot tolerate copious amounts of it; not much different from obligate aerobes; microaerophiles love (-phile) just a little (micro-) oxygen (aero)

Aerotolerant Anaerobes

metabolize via several types of fermentation which does not require oxygen to generate energy; can live anywhere and able to cope with oxygen (but prefers a smaller amount)

Facultative Anaerobes

prefer to metabolize via aerobic respiration (and therefore prefers oxygen-rich environments) but are able to switch to fermentation when oxygen availability is poor

Obligate Anaerobes

metabolize via fermentation and can only survive in the absence of oxygen; oxygen causes sporulation in some cells and kills others (methanogens)

Pseudomonas

obligate aerobe that causes pneumonia and can grow in places with oxygen and evading the immune system; particularly harmful for burn victims and anyone immunosuppressed

Campylobacter

a microaerophile that causes massive issue in the poultry industry because it has to hide from too much oxygen; able to evade chlorine used to wipe out Salmonella because the chlorine is used topically (on the skin, not under it)

Clostridium

genus of obligate anaerobe, Gram positive bacteria that form endospores in the presence of oxygen and cannot reproduce; O2 does not kill the existing cells (endospores wait until favorable conditions to convert back into a vegetative cell) often found in soil, water, and animal intestines

Lactobacillus

thrives in the GI tract and female genitourinary area; outcompetes pathogens and origin of the vaginal pH

Protista

 any eukaryotic organism that is not an animal, land plant, or fungus; typically unicellular but can also exist as colonies of cells

Bacillus stearothermophilus

thermophile used to test autoclaves; one of the most heat resistant microbes known to man; cannot survive the autoclave, so it can be used to test the function of the autoclave by running a sample through it and then culturing it

ATPsynthase

protein that generates ATP in organisms that perform respiration (anaerobic and aerobic) by binding a third phosphate group onto a molecule of ADP by using the energy generated from the flow of electrons