Bio 204: Microbiology Study Notes For Test 1

Front 1

What is a microorganism?

Back 1

An organism too small to be seen without a microscope

Front 2

What are the 3 domains of the current system of classification?

Back 2

Bacteria, Archaea, Eukarya

Front 3

What are the 4 kingdoms of eukaryotes?

Back 3

Protista, Fungi, Animalia, Plantae

Front 4

What are the general, distinguishing characteristics of bacteria?

Back 4

- prokaryotes
-peptidogylcan cell wall
- unicellular and lack nuclei
- reproduce asexually
- much smaller than eukaryotes
- found everywhere there is sufficient moisture

Front 5

What are the general, distinguishing characteristics of archaea?

Back 5

- prokaryotes
- pseudopeptidoglycan cell wall
- unicellular and lack nuclei
- reproduce asexually
- much smaller than eukaryotes
- many live in extreme environments

Front 6

Three types of archaea that live in extreme environments

Back 6

Methanogens (decomposers, methane)
Halophiles (salt loving)
Thermophiles (heat loving)

Front 7

General characteristics of algae

Back 7

Eukaryote
Kingdom Protista
Photosynthetic
Unicellular or multicellular
Reproduce asexually OR sexually
Most are sessile
Categorized by storage products, pigmentation, cell wall composition

Front 8

General characteristics of protozoans

Back 8

Eukaryote
Kingdom Protista
Unicellular
Heterotrophic
Free-living in water, or parasitic in host
Reproduce asexually or sexually
Most are motile

Front 9

Sessile

Back 9

Fixed in one place, immobile

Front 10

Motile

Back 10

Able to move spontaneously and actively

Front 11

General characteristics of fungi

Back 11

Eukaryote
Kingdom Fungi
Unicellular or multicellular
heterotrophic detrivores
Reproduce asexually OR sexually
Cell walls made of chitin

Front 12

2 types of fungi

Back 12

Molds
yeasts

Front 13

heterotrophic detritivores

Back 13

obtain nutrients by consuming detritus (decomposing organic matter)

Front 14

Characteristics of molds

Back 14

type of fungi
multicellular
grow hyphae
reproduce by spores

Front 15

Characteristics of yeasts

Back 15

type of fungi
unicellular
reproduce by budding
some produce spores

Front 16

General characteristics of viruses

Back 16

Acellular
Obligate parasites
Host and/or tissue specific
basic types have a protein coat and nucleic acid, no membrane
- Can't be seen w/o electron microscope

Front 17

Robert Hooke

Back 17

early observations 1665
coined the term "cell"
observed dead cork cells in plants

Front 18

Antoni von Leeuwenhoek

Back 18

1673 - 1723
lensmaker, created first microscope (primitive), discovered "animalcules / beasties" in plaque and pond water

Front 19

Francesco Redi

Back 19

1626 - 1697
Did experiments to investigate spontaneous generation (meat in open jar, corked jar, and jar covered with gauze)

Front 20

Louis Pasteur

Back 20

1861 - swan neck flask experiments disproved spontaneous generation (abiogenesis)
- germ theory of disease
- fermentation
- discovered facultative anaerobes
- introduced industrial microbiology

Front 21

Robert Koch

Back 21

- 1843 - 1910
- Koch's Postulates
1. causative agent must be found in all cases of the disease and absent in healthy hosts
2. agent must be isolated and grown outside the host
3. when agent is introduced in healthy host, the host must get the disease
4. Same agent must be re-isolated from the diseased experimental host

Front 22

Hans Christian Gram

Back 22

- 1884
- Gram stain
- Differentiation of bacteria based on staining procedures
- Two types of bacteria (Gram positive or Gram negative)
- Allowed Koch's 1st postulate to be tested

Front 23

Ignaz Semmelweis

Back 23

- 1818 - 1865
- Suggested physicians wash hands before examining patients
- reduced maternal death rate from puerperal fever from 12 % to 1 %
- Father of Aseptic Technique

Front 24

Joseph Lister

Back 24

- 1827 - 1912
- Recognized Semmelweis's work
- Lister's Antiseptic Technique
1. spray wounds and incisions with carbolic acid
2. soak surgical instruments and dressings

Front 25

Florence Nightingale

Back 25

1820 - 1910
- observed that death rates were higher in hospitals than battlefields during Crimean War
- Called for fresh water, improved hygiene, fresh food
- established Nightingale School of Nursing

Front 26

John Snow

Back 26

1823 - 1854
- pioneer of epidemiology
- mapped London cholera outbreak in 1854, isolated source to the local water pump
- advised officials to remove handle of pump
- when done, this contained the epidemic

Front 27

Edward Jenner

Back 27

1749 - 1823
- Pioneer of immunology
- Observed that milk maids who had cow pox were immune to small pox
- injected boy with cow pox, then small pox ... boy was immune
- Vaccinations (vacca is Latin for cow)

Front 28

Paul Ehrlich

Back 28

- 1854 - 1915
- pioneer of chemotherapy
- hunted for the magic bullet (harmful to microbes, not the host)
- identified Salvarsen (salvation using arsenic), effective against syphilis

Front 29

What are the steps of the scientific method?

Back 29

- observations
- questions
- hypothesis
- experimentation
- accept, reject, or modify hypothesis

Front 30

Some achievements of the modern age of microbiology

Back 30

- understanding of the shared biochemistry of all life (the transfer of e- and H+)
- identification of the domain archaea using molecular techniques
- use of genetic engineering to produce drugs in microbes (insuline, hGH)
- discovery of new species of microbes through genetic prospecting
- understanding that bacteria are essential to the environment (nitrogen fixation, decomposition, mutualism)

Front 31

Why is understanding cell structure and function important to humans?

Back 31

understanding cells allows us to:
- understand how microbes cause disease
- understand how microbes defend themselves
- develop treatments to inhibit or kill microbes
- not harm our own cells in the process

Front 32

basic characteristics of living organisms

Back 32

- cells (cell theory)
- growth and development
- reproduction
- responsiveness
- metabolism
- evolution and adaptation to environment

Front 33

glycocalyx of bacteria

Back 33

slime layer and capsule
gelatinous sticky substance composed of polysaccharides, polypeptides, or both. Protects cells from dessication.
prevents drying out/dehydration

Front 34

pathogen with glycocalyx

Back 34

streptococcus pneumoniae
pneumococcal pneumonia
pathogenesis due to capsule

Front 35

flagella of prokaryotes

Back 35

composed of proteins
differences in proteins identify serovars (in blood - serum)
allow motility and taxis

Front 36

taxis

Back 36

movement toward or away, in one direction

Front 37

flagella arrangements

Back 37

monotrichous
lophotrichous
amphitrichous
peritrichous

Front 38

runs and tumbles

Back 38

reg. flagella:
runs result from counterclockwise rotation, tumbles result from clockwise rotation
runs in one direction, but can tumble when something is detected that would cause harm

Front 39

characteristics of flagella

Back 39

rotate 360 degrees at over 100,000 rpm
can change from counter clockwise to clockwise
runs punctuated by tumbles
multiple flagella always rotate in unison
receptors signal flagella to adjust speed and direction of rotation

Front 40

pathogen with flagella

Back 40

Helicobacter pylori (lophotrichous flagella)

Front 41

endoflagella (axial filament)

Back 41

endoflagella form axial filaments, allow spirochete motility
(spirochete corkscrews and moves forward)

Front 42

pathogen with endoflagella

Back 42

Borrelia burgdorferi
(Lyme's disease) the spiraling movement of bacteria facilitates penetration of host tissues.

Front 43

fimbriae

Back 43

attachment in Gram negative cells
shorter than flagella
hundreds per cell
can act as "grappling hooks"
important in formation of biofilms

Front 44

pathogen with fimbriae

Back 44

Neisseria gonorrhea
fimbriae attachment to epithelial cells of reproductive tract

Front 45

pili

Back 45

- conjugation and genetic exchange
longer than fimbriae
shorter than flagella
allow exchange of genetic information

Front 46

internal structures of prokaryotic cells

Back 46

plasmids, endospores, inclusions, nucleoid region, ribosome, cytosol, cytoskeleton

Front 47

plasmids

Back 47

extra chromosomal DNA, special genes

Front 48

endospores

Back 48

- the main chromosome of bacterial cells
- thick protective coat
- protected copy of bacterial chromosome
- resistant to drying, heat, radiation, chemicals

Front 49

inclusions

Back 49

reserve deposits of lipids, starch, nitrogen compounds, sulfur

Front 50

nucleoid region

Back 50

not a nucleus, circular, naked, single chromosome

Front 51

ribosome

Back 51

two subunits - 50S and 30S = 70S (sedimentative, not a direct correlation)
Proteins and RNA

Front 52

cytoskeleton

Back 52

protein filaments

Front 53

what is the shape of a bacterial cell determined by?

Back 53

cell wall

Front 54

what are the arrangements of bacterial cells?

Back 54

chains
packets
clusters

Front 55

what are the basic shapes of prokaryotic cells?

Back 55

coccus, bacillus, spirillum

Front 56

describe bacterial cell wall composition

Back 56

they have a carbohydrate backbone of alternating peptidoglycan sugars (NAG - N-acetylgucosamine) and (NAM - N-acetylmuramic acid), connected vertically by tetrapeptide crossbridges and horizontally by connecting chains of amino acids.

Front 57

chains

Back 57

cells divide in one plane (streptococcus spp)

Front 58

packets

Back 58

cell divides in two or more planes perpendicular to each other (Sarcina spp)

Front 59

clusters

Back 59

cell divides in several planes at random (Staphyloccus spp)

Front 60

teichoic acid

Back 60

unique polyalcohol found in Gram positive cell walls. Can be covalently linked to lipids, forming lipoteichoic acid.

Have a negative charge, give the surface of Gram-positive cells a negative charge and affect ion passage.

Front 61

lipopolysaccharide

Back 61

The outer leaflet of Gram-negative cell walls. The lipid portion is known as Lipid A.

Front 62

lipid A

Back 62

The lipid portion of LPS. It is released from the LPS when the cell dies.
can cause shock, blood clotting, and fever in humans

Front 63

porin

Back 63

proteins that cross a cellular membrane and act as a pore through which molecules can diffuse.

Front 64

periplasmic space

Back 64

space that contains periplasm, it is between the outer membrane and the cell membrane of Gram-negative organisms.

Front 65

group translocation

Back 65

type of active transport, occurs in some prokaryotes

the substance being carried across the cell membrane is chemically changed during transport.

Very efficient at bringing substances into a cell

Front 66

why are Gram-negative cells more pathogenic than Gram-positive

Back 66

the outer membrane may prevent the movement of penicillin to the underlying peptidoglycan

killing a cell causes it to release lipid A, which makes people more sick.

Front 67

what are the differences between Gram positive and Gram negative cell walls?

Back 67

The G-+ cell wall has a thick layer of peptidoglycan and teichoic acids that anchor the wall to the cell membrane.

The G - cell wall has a thin layer of peptidoglycan and an outer membrane composed of LPS, phospholipids, and proteins.

Front 68

simple diffusion

Back 68

movement of a chemical down a concentration gradient, from high concentration to lower. Requires no energy output from the cell.

Front 69

facilitated diffusion

Back 69

movement of substances across a cell membrane through channel proteins.

no energy required from the cell, it is provided by electrochemical gradient

Front 70

active transport

Back 70

the movement of a substance against its electrochemical gradient via carrier proteins.

Requires ATP

Front 71

uniport system

Back 71

one substance transported at a time

Front 72

antiport

Back 72

simultaneously transport 2 chemicals, but in opposite directions ... one in, one out

Front 73

cotransport

Back 73

uniport and symport,

Front 74

isotonic

Back 74

solutions on either side of a selectively permeable membrane have the same concentration of solutes.

neither side of a selectively permeable membrane will experience a net movement of water

Front 75

hypertonic

Back 75

concentrations of solutes are unequal, the solution with the higher concentration is hypertonic

cells in hypertonic solutions shrink due to the net movement of water out of the cell.

Front 76

hypotonic

Back 76

the solution with lower concentration of solutes is hypotonic in comparison

cells in hypotonic solutions undergo a net gain of water. animal cells burst, in plants (cells with a wall) the pressure of the water pushing against the interior movement of the wall eventually stops the movement of water into the cell.

Front 77

Streptococcus pneumonia

Back 77

cellular structure - GLYCOCALYX contributes to pathogenesis

pneumonia

Front 78

Heliobacter pylori

Back 78

pathogenesis due to strong
LOPHOTRICHOUS flagella

stomach ulcers, stomach cancer

Front 79

Borrelia burgdorferi

Back 79

pathogenesis due to spiraling movement of endoflagella

Lyme disease

Front 80

Neisseria gonorrhea

Back 80

pathogenesis from fimbriae attachement to epithelial cells of reproductive tract

Gonorrhea, PID, epidymitis

Front 81

what are the energy sources used for light microscopy

Back 81

the energy of electrons, electrons are shot at the image

Front 82

magnification

Back 82

the apparent increase in the size of an object that results from the bending or refraction of light as it passes through a lens

Front 83

empty magnification

Back 83

lacks clarity

Front 84

why does a blue filter enhance resolution?

Back 84

blue light provides shorter wave length ratiation

Front 85

resolution

Back 85

the ability to distinguish between objects that are close together

Front 86

difference between a simple microscope and a compound microscope

Back 86

a simple microscope contains a single magnifying lens

compound light microscopes have more than one magnifying lens (ocular and objective), uses visible light passing through a specimen (light source and blue filter).

Front 87

contrast

Back 87

differences in intensity between two objects

Front 88

condenser

Back 88

focuses light through specimen

Front 89

diaphragm

Back 89

controls the amount of light entering the condenser

Front 90

coarse focusing knob

Back 90

moves stage up and down to focus the image

Front 91

body

Back 91

transmits the image from the objective lens to the ocular lens using prisms

Front 92

ocular lens

Back 92

remagnifies the image formed by the objective lens

Front 93

how is total magnification calculated

Back 93

ocular magnification x objective magnification

Front 94

what is a simple stain?

Back 94

composed of a single basic dye, ex: crystal violet
types of info: size, shape, arrangement of cells

Front 95

differential stain

Back 95

more than one dye is used (Gram stain, acid fast stain, endospore stain), allows for different cells, chemicals or structures to be examined

Front 96

types of organisms identified by an acid fast stain

Back 96

stains cells of the genera mycobacterium and nocardia. These types of cells have a waxy lipid in their cell walls that doesn't work well with the Gram stain.

Front 97

special stain

Back 97

special stains are simple stains designed to reveal special microbial structures (ex: negative stains, flagellar stains, fluorescent stains)

Front 98

why is Carl Woese important in the field of taxonomy?

Back 98

compared rRNA subunits in cells

proposed a new classification system to reflect differences:
eukarya, bacteria, archaea

Front 99

phage typing

Back 99

method of classifying microorganisms in which unknown bacteria are identified by observing plaques

Front 100

serology

Back 100

the study and use of immunological tests to diagnose and treat disease or identify antibodies or antigens

Front 101

how is a dichotomous key used?

Back 101

stepwise between paired characteristics to assist in identifying microbes