quiz 1 microbiology

absorbance

absorbance

when a material captures the energy of a light wave

acellular organisms

without cells, not living

algae

type of protist, plant- like, can be uni or multicellular, do have cell walls made of cellulose, generally photosynthetic, don’t really cause human disease, can be found in gelatin and toothpaste

protists

eukaryotic organisms that are not plants, animals, or fungi

amplitude

height of each peak

antonie van leeuwenhoek

developed very first microscope, first to see microorganisms, he took a drop of water and called them “animalcules” or “wee little beasties”

archaea

one of the 3 domains, prokaryote, tend to be unicellular, cell walls made of pseudopeptidoglycan, tend to live in extreme environments, not currently known to cause any human disease, more genetically related to eukaryotes than bacteria

bacteria

one of the 3 domains, prokaryotic, genetic material is not housed within a true nucleus, most have cell walls that contain peptidoglycan, most are unicellular

Bergey’s manuals

used to classify prokaryotes, usually bacteria, based on serological and biochemical properties

binomial nomenclature

naming microbes, genus then species, genus always capitalized and species always lowercase, can be written as first letter capitalized, a period, then last name lowercase

brightfield microscope

most common microscope; bright background with a dark subject

candida albicans

unicellular fungus, or yeast; causative agent of vaginal yeast infections as well as oral thrush

cell theory

cells are the basic unit of life, all living things are made up of cells, all cells come from other cells

cell wall

structure that encompasses the cell membrane, protects the cell from changes in osmotic pressure, stains differentiate bacteria based on cell wall composition

cytoskeleton

matrix of fiber and tubes that provide structural support for the cell; can provide a route for materials/ vesicles to be transported in the cell

darkfield microscope

dark background with a bright subject

endomembrane system

unique to eukaryotes, a series of membranous compartments that synthesize and move components around the cell

endoplasmic reticulum

part of the endomembrane system, interconnected flattened disks that synthesize materials for the cell (rough ER: studded with ribosomes, synthesize proteins / smooth ER: appears smooth, no ribosomes, synthesizes lipids and carbs)

endospores

characteristic of prokaryotic cells, structures that protect the bacterial genome in a dormant state, can survive in dormant state for thousands of years

eukarya

one of the 3 domains (humans)

eukaryotes

have a true nucleus, except red blood cells

fermentation

chemical breakdown of a substance by bacteria, yeasts, or other microorganisms

fixation

taking either heat or chemicals and killing it and sticking it to the glass slide, permanently attached to slide, allows you to see more distinguishing features, allows you to dye the substance (types: chemical and heat)

francesco redi

disputed spontaneous generation by creating an experiment where he put rotting pieces of meat in an open container, sealed container, and one covered in gauze. the open container had maggots on the meat. the gauze- covered container had maggots on the gauze.

frequency

number of wavelengths in a specific time period (low= less waves, high= more waves)

fundamental components of cells

cytoplasm, membrane, chromosomes, ribosomes

cytoplasm

gel like substance inside of the cell

membrane

surrounds the cytoplasm, separates the inside of the cell from the outside

chromosomes

contain genetic blueprint of the cell, gives instructions on how to make a new cell

ribosomes

all cells have them, used for synthesizing proteins, prokaryotic are smaller / eukaryotic- can be clinically important as it relates to antibiotics

prokaryotic cells

lack a nucleus, can have a nucleoid, don’t have its own membrane, usually have a single circular chromosome, lack membrane- bound organelles, usually smaller

eukaryotic cells

separate nucleus surrounded by a nuclear membrane, usually contain multiple, rod- shaped chromosomes, contain several membrane bound organelles, usually larger

fungi

eukaryotic microorganism, cell walls usually composed of chitin (unicellular: yeasts; multicellular: molds)

germ theory of disease

idea that diseases are caused by germs

Giralamo Fracastoro

early proponent of germ theory, wrote a pamphlet called De Contagione et Contagiosis, found that "seed- like spores” could be transferred through the air, clothing, or direct contact (person to person)

gram stain

most common type of staining, uses 2 different dyes, distinguishes organisms based on whether they turn dark purple (crystal violet)- gram positive or pink (safranin)- gram negative

haploid

only one copy

helminths

eukaryotic microorganism, multicellular parasitic worms, larvae and eggs are typically microscopic

hypertonic

HIGHER solute concentration than another solution; water moves out of the cell, causing it to shrink

hypotonic

LOWER solute concentration than another solution, water moves into the cell, causing it to expand and eventually burst

Ignaz Semmelweis

proposed that physicians wash their hands between patients. he noticed that when a physician attended a birth, 20 % of the time either mother and/or child died from postpartum fever. he noticed that when a midwife attended a birth, only 1% of the time did the mother and/ or child developed fever and died. the midwives only delivered babies, but the physicians saw all kinds of sick patients and delivered babies.

inclusions

special to prokaryotes, groupings of excess nutrients, toxins, and proteins that they store for themselves, reduces buildup of osmotic pressure

isotonic

water moves in and out of cell, overall concentration on both sides of the cell membrane remains constant, has the SAME solute concentration as another solution

joseph lister

50% of his patients died from fever after having performed surgery. he took semmelweis’s handwashing technique and used it. he began forcing everyone to clean everything that might come into contact with a person during surgery. carbolic acid spray was used to disinfect surfaces (listerine was named after him)

louis pasteur

created pasteurization to kill microorganisms in food, also developed rabies vaccine, disproved spontaneous generation (created curved neck flasks that allowed air to come in and out. dust and physical particles could not get past the curve in the flask. he filled the flasks with broth, made them sterile, then left them. when the flask was curved, the broth stayed clear. when the flask was not curved, the broth became contaminated. the contamination was caused by the microorganisms in the dust.

lysosomes

small organelles that contain digestive enzymes, allow cells to perform phagocytosis and destroy macromolecules

magnification

ability of a lens to enlarge an image

microscopy

science of using microscopes

microorganisms

too small to be seen with the naked eye, can be multicellular, found everywhere on earth

nucleoid

characteristic of prokaryotic cell, condensed area of DNA, chromosomes are usually haploid and not bound by a membrane

opacity

solid, not see through

osmotic pressure

occurs because of differences in concentrations of solutes

peptidoglycan

protein found in cell walls

phylogenies

taxonomy that takes evolutionary relationships into account (early: easily seen with eyes / modern: genetics, biochemical properties, not easily observable, can it eat lactose, glucose, and citrate as a food source?

plasmid

characteristic of prokaryotic cell, extra bits of extrachromosomal DNA, can often carry genes that can be advantageous (extra toxins, antibiotic resistance)

prokaryotes

don’t have a true nucleus

protozoa

type of protist, animal- like, tend to be unicellular, no cell wall, feed on organic matter `

reflection

when a light wave bounces off a material (white- reflects all colors / black- absorbs all colors)

refraction

occurs when light waves change direction as they move through different materials

resolution

ability to tell that 2 separate points or objects are separate (blurry = low resolution; not blurry = high resolution)

ribosomes

characteristic of prokaryotic cell, used for synthesizing proteins, smaller than eukaryotic ribosomes

in eukaryotic cells, ribosomes

can be clinically important as it relates to antibiotics

robert koch

proved a human disease was caused by a single bacteria

rough ER

studded with ribosomes

saccharomyces spp.

yeast responsible for making bread rise

smooth ER

no ribosomes, appears smooth

theory of spontaneous generation

idea that life can arise from non- living matter

Thucydides

father of scientific history, first person to note plague in athens that killed 1/3 of the population, found out that previously infected people could not get it again

taxonomy

process of classifying different organisms based on description and identification

linnaean taxonomy

first to create categories of organisms (3: animals, plants, and minerals)

transmittance

when a wave travels through a material

transparency

see through

Trichomoniasis

very common STD caused by infection with Trichomonas vaginalis, a protozoan parasite

viruses

organisms not composed of cells, contain proteins and some sort of genetic material (either DNA or RNA), cannot survive outside of a host cell, takes over the host cell, doesn’t only infect humans, lack ribosomes, infect other cells to take over their ribosomes and metabolic properties

wavelength

distance between peaks

wet mount

put it on microscope slide and look at it, very easy, still alive, can see changes in movement, cannot use immersion oil, highest you can go is 40x

chloroplasts

eukaryotic organelle, at least 3 membrane systems, photosynthesis- creating energy from light

golgi apparatus

part of endomembrane system, series of flattened disks that contain enzymes that change the materials produced in the ER, produces glycolipids and glycoproteins

lysosomes

part of the endomembrane system, small organelle that contains digestive enzymes, allows cell to perform (phagocytosis- cell eating) and destroy macromolecules

endospores

characteristic of prokaryotic cells, structures that protect the bacterial genome in a dormant state, can survive in dormant state for thousands of years

clostridium botulinum

cause of botulism, can survive a lot of food preservation methods due to endospores, specifically canning

clostridium difficile

lives in the digestive tract of humans, forms endospores, very hard to kill

filamentous appendages in prokaryotic cells

fimbriae and pili- similar structures that aid in surface attachment (reaching or grabbing) or DNA transfer / Flagella- used for movement in aqueous environments, usually rotational, propels bacteria forward (TAIL)

filamentous appendages in eukaryotic cells

flagella- used for locomotion and more whiplike, larger, 1 or 2 / cilia- shorter appendages used for locomotion or “sweeping” and use a faster waving motion, millions of these

mitochondria

eukaryotic organelle, double membrane, aerobic cellular respiration- produces energy from chemicals

morphology (cell shape)

prokaryotic- maintained by the cell wall, only a handful identified / eukaryotic- morphology is much more varied than prokaryotic cells

coccus

round

bacillus

rod

vibrio

curved rod

coccobacillus

short rod

spirillum

spiral

spirochete

long, loose, helical spiral

nucleoid

characteristic of prokaryotic cell, condensed area of DNA, chromosomes are usually haploid and circular, and not bound by a true nuclear membrane

nucleus

eukaryotic cells- DNA genome is contained within a complex membrane, controls all activity of the cell, typically have DNA organized into multiple linear chromosomes, cell has total control because the chromosomes are condensed

typical prokaryotic cell

has a cell membrane, unicellular, most have cell walls, chromosomal DNA within a nucleoid, ribosomes, may have flagella, pili, fimbriae, and capsules

why can bacteria become resistant to antibiotics very quickly?

plasmids

antibiotics tend to focus on ways the prokaryote is different from the eukaryote, which are

ribosomes and the cell wall

plasma membrane

characteristic of prokaryotic cells, allows for selective permeability, most are a bilayer with embedded proteins