Microbiology: Exam 1

circle logic

the end is the beginning for either the same cycle or for the next part of the cycle

antibiotic resistance

when bacteria/fungi develop the ability to defeat the antibiotics designed to kill them

epidemiology

study of the frequency, distribution, and spread of disease

fulminant

severe and sudden onset of disease or symptom

pathogenesis

study of how/why diseases develop; why one bacteria causes one disease while another causes a different disease

host defense

study of how we survive infection and why

prevention

an almost nonexistent part of modern medicine; treatment and control

virulence

degree of pathogenicity; infectivity of the agent and the severity of the disease it causes

virulence factors

factors porduced by the infectous agent that affect the agents virulence; ability to live and feed in host

innate immunity

organism’s nonspecific host defenses against infection

adaptive immunity

organism’s specific host defenses against infection; develops after initial infection

sterilization

complete killing of vegetative cells and endospores

sanitation

cleaning dust and dirt from surface

antisepsis

killing of all vegetative cells, but not spores from a biological surface

disenfection

killing of all vegetative cells, but not spores from inanimate surfaces

macromolecules

carbohydrates, lipids, nucleic acids, proteins

simple sugar

glucose

complex sugar

disaccharide

common complex sugars

glycogen, plant starches, and cellulose

lipids

nonpolar molescules; used in cell membranes for structure and in cell for energy

phospholipid

polar head group and nonpolar tail; make up cell membrane

isoprenoid lipids

5 carbon lipids that can be used to make chains or rings

proteins

amino acids

peptide bonds are made through this

dehydration synthesis

peptide bones are broken through this

hydrolysis

nucleic acids

make up DNA and RNA

polymers

chains of units

3 domains of life

bacteria, archaea, and eukarya

strain

specific subgroup of the species that is different from other subgroups

serotype

grouping with antibodies

prokaryotes

bacteria and archaea

eukaryotes

humans, fungi, and protists

differences between prokaryotic cell and eukaryotic cells

eukaryotic cells have membrane bound organelles and a nucleus. prokaryotic cells have no organelles and no nucleus

membrane

layer of lipids that separates from the outside world

genome

DNA instructions for making proteins and RNA

RNA

interpreter of DNA to make protein

protein

workhorse, struture, hands that bring things into the cell

simple staining

all cells are one color; basic dye added to (-) bacteria cells

negative staining

background is stained while cells remain clear; acidic dye added to (-) bacteria cells; stain cannot invade cells

gram staining steps

add crystal violet, add iodine, alcohol wash, add saphranin

makes all cells purple, washes stain out of gram negative cells, gram negative cells are pink

capsule stain

combination of negative stain followed by simple stain; stain background and inside structure to reveal capsule of bacteria cell

endospore stain steps

malachite green, steam, water, saphranin

stains all cells green, ensures stain penetrates cell capsule, washes nonendospores, stains other cells red

acid-fast stain steps

carbolfushsin, steam, acid alcohol wash, methtlylene blue

stains cells pink, ensures stain penetrates cell capsule, washes stain from cells without waxy cell wall, stains negative cells blue

nucelus

contains genome (DNA) information; many viruses replicate or insert their own DNA into host

cytoskeleton

actin, microtubules, and intermediate filaments that make up fibrous network that determines shape of eukaryotic cells

act as track vesicles can be transported on

centriole

microtubule organization center of cell in 9+0 array

microfilaments

made of actin, movement, and surface cell shape

microtubules

flagella and cilia, intracellular organization

intermediate filaments

provide strength and nuclear shape; link cells

cilia

short “whips” that help move mucus and trap bacteria

sterols

one mechanism of adjusting the fluidity of the membrane

roles of cell membrane

barrier to infection and outside environment, pathogens have to bind to receptor on membrane to passively or actively enter the cell

major site of energy metabolism; making ATP

semi-permeable barrier; small ions (o2, co2, n2) and uncharged molecules (water, gylcerol and ethanol)

role of cell wall

protecting membrane from lysis

facilitated diffusion

moves with concentration gradient; passive transport with help of transport protein embedded in membrane

active transport

moves against concentration gradient; uses ATP energy to facilitate transport

group translocation

use of energy to move and modify a molecule as it is brought across the membrane

cytoplasm

main location for the cell’s biochemical and biosynthetic activites

ribosome

protein synthesis machines; often hijacked by viruses

ER (rough and smooth)

part of nuclear envelope; proteins can be modified here

golgi bodies

specific modifications of proteins, all proteins for membrane and outside the cell must pass through (post office; sorting)

lysosomes

“stomach” of cell; important in the destruction of things brought into the cell, important in immune cells

endocytosis

taking things into the cell inside the membrane vesicles

pinocytosis

“cell drinking” small vesicle intake

phagocytosis

“cell eating” large vesicle intake

receptor-mediated endocytosis

specific signal binding to a receptor and causing specific uptake of vesicle into the cell

exocytosis

secreting things out of the cell from inside of membrane vesicles

peptidoglycan

cell wall of eubacteria

lysozyme

cleaves peptidoglycan

endospores

gram positive bacteria in dormant form; no metabolic activity

capsule

prevents phagocytosis by immune cells, functions as adhesion, forms glycocalyx, holds water

pili/fimbriae

long rods that stick out from surface of the cell, made of pilin, involved in adhesion and twitching motility, genetic transfer in bacteria

flagella

long filaments that allow for rapid movement of the cell

prokaryotic vs eukaryotic flagella

prokaryotic: composed of flagellin and moved by rotating

eukaryotic: made of microtubules in 9+2 array and beat in ones direction

cilia

only in eukaryotes; much shorter and many of them on cell; propel with whip movement

axial filaments

flagella between two membranes; only found in spirochetes

phase variation

some organisms can change whether pili are on/off so they are not detected

antigentic variation

change kind of pili

nucleoid

location where DNA is concentrated in bacteria cells

plasmids

non-essential DNA that make a difference in virulence and antibiotic resistance

quorum sensing

secretion of autoinducer compound that allows for other cells to detect presence of neighboring cells

biofilms

group of bacteria growing as a film on a surface

biofilm formation

bacterial adherence, microcolony formation, pedestal formation

what infects man?

plants, animals, fungi, protists, bacteria, viruses, and animal parasties

colonization

the act of the agent binding to and taking up residence in the host

infection

occurance of the infectious agent in the host, which may or may not lead to disease

disease

infectious agent damages the host in some way that reduces the fitness of the host often producing obvious symptoms

immune evasion

organism must have strategy to avoid immune clearance; many ways to do this

proliferation

organism must multiply to maintain infection. if organism does not divide it will be sloughed off with epithelium

penetration

MOST infectious agents must somehow enter host tissue to cause disease

transmissibility: 3 needs

need sufficient numbers

need to get to new host

need suspectible host

candy jar disease

severe disease that is not beneficial to host or the pathogen; rapid death of host

accidental host

alternate host that may or may not be able to transmit the disease

portals of entry

mucosal membranes: eyes, nose, inner ear, sinus, mouth, respiratory, gastrointestinal, urogenital

lung, skin, vector borne, transplacental, kidney, bloodborne

fecal-oral route

major way into the body; non-traditional way for some pathogens

parenteral route

not coming into the body via mouth/anus

types of infection

disease is often characterized by onset of symptoms

tissue tropism

organism is generally limited to certain tissues or sites; affect certain tissue or target site

localized

agent remains in one area

toxigenic bacteria

remain localized but secretes toxins that are able to spread through tissues or survive in circulatory system