Modules 1-3 Objectives

Question 1

Robert Hooke’s contributions

Answer 1

Discovered cells
Cell theory
first microscope

Question 2

Edward Jenner’s contributions

Answer 2

Found smallpox cure
first vaccine
took cowpox scrapings

Question 3

Louis Pasteur’s contributions

Answer 3

Theory that germs cause disease
disproved the theory of spontaneous generation
Microbial life can be destroyed by heat and can block access of airborne microorganisms
basis of aseptic techniques
discovered pasteurization
found why vaccines worked
used weakened cells for vaccine

Question 4

Joseph Lister’s contributions

Answer 4

applied germ theory to medical procedures
discovered the first disinfectant (phenol)

Question 5

Robert Koche’s contributions

Answer 5

First proof that bacteria caused disease (Koch’s postulate)
Worked with Petri to develop the petri dish

Question 6

Paul Ehrlich’s contributions

Answer 6

discovered arsphenamine (Salvarsan), the first effective medicinal treatment for syphilis
developed a chemical theory to explain the body’s immune response and did important work in chemotherapy, coining the term magic bullet

Question 7

Alexander Fleming’s Contributions

Answer 7

discovered penicillin

Question 8

Wendall Stanelys’ contributions

Answer 8

discovered the tobacco mosaic virus
smaller than bacteria and could pass through a filter
could be crystalized like chemicals

Question 9

Define microorganisms

Answer 9

Minute living organisms that are individually too small to be seen with the naked eye

Question 10

benefits of microorganisms

Answer 10

form basis of food chains in oceans, lakes, and rivers
help break down wastes in sewage disposal
Photosynthesis
Present in intestine for digestion and synthesis of vitamin k and vitamin b
used in the synthesis of chemical products
used in food industry to produce foods

Question 11

Describe microbial classifications

Answer 11

bacteria
fungi
protozoans
microscopic algae
viruses

Question 12

Scientific nomenclature for bacterial names

Answer 12

The genus:
Capitalized
first
italicized

The species:
lowercase
second
italicized

Question 13

Compare and contrast prokaryotic and eukaryotic cytoplasmic and cell envelope structures and functions

Answer 13

Like a prokaryotic cell, a eukaryotic cell has a plasma membrane, cytoplasm, and ribosomes, but a eukaryotic cell is typically larger than a prokaryotic cell, has a true nucleus (meaning its DNA is surrounded by a membrane), and has other membrane-bound organelles that allow for compartmentalization of functions.

Question 14

The three basic shapes of microorganisms

Answer 14

cocci (sphere)
bacilli (rod)
Spirochetes (spiral)

Question 15

Describe the reproductive process of bacteria, and the stages in growth of the bacterial cells

Answer 15

bacteria reproduce primarily by fission, or direct division. During mitosis, a parent cell is divided into 2 daughter cells by creating a septum that directly separates the parent cell in half

Question 16

Differentiate between gram positive and gram negative bacteria

Answer 16

Gram positive:
thicker layer of peptidoglycan
cell walls contain teichoic acid
teichoic acid help prevent cell wall lysis

Gram negative:
small amounts of peptidoglycan
no teichoic acids
peptidoglycan layer surrounded by an outer membrane consisting of lipopolysaccharides (LPS), lipoproteins, and phospholipids
alkaline dye of gram stain washes out

Question 17

atmospheric requirements of obligate aerobes, microaerophiles, facultative anaerobes and obligate anaerobes

Answer 17

The bacteria are obligate (strict) aerobes that cannot grow without an abundant supply of oxygen.
Those are obligate anaerobes, which are killed by oxygen.
Facultative anaerobes are organisms that thrive in the presence of oxygen but also grow in its absence by relying on fermentation or anaerobic respiration, if there is a suitable electron acceptor other than oxygen and the organism is able to perform anaerobic respiration.
The aerotolerant anaerobes in tube D are indifferent to the presence of oxygen. They do not use oxygen because they usually have a fermentative metabolism, but they are not harmed by the presence of oxygen as obligate anaerobes are.
These microaerophiles are bacteria that require a minimum level of oxygen for growth, about 1%–10%, well below the 21% found in the atmosphere.

Question 18

Define atmospheric requirements of microorganisms

Answer 18

If oxygen is acceptable or not for growth

Question 19

List the possible routes of laboratory-acquired infections

Answer 19

Inhalation (see aerosols)
Percutaneous inoculation (needle and syringe, cuts or abrasions from contaminated items and animal bites)
Contact between mucous membranes and contaminated material (hands or surfaces)
Ingestion (aspiration through a pipette, smoking or eating)

Question 20

List the agencies that govern laboratory safety in the microbiology department

Answer 20

Occupational Safety and Health Administration (OHSA)
National Fire Protection Agency (NFPA)
The Joint Commission (TJC)
College of American Pathologists (CAP)

Question 21

Delineate the roles the laboratory technologist plays in an infection control program

Answer 21

Monitors infections in the facility
Infection control procedure development
The primary objective of biological safety is preventing the completion of the chain of infection

Question 22

Correlate the role of the laboratory with the safety guidelines and the prevention of nosocomial infections

Answer 22

Appropriate safety measures should include a routine, deep cleaning of all areas of the hospital, both in-patient and out-patient, to minimize communicable transmission infectious diseases.

Question 23

Define sterilization

Answer 23

The process of destroying all forms of microbial life on an object or in a material

Question 24

define bacteriostatic

Answer 24

A condition in which bacterial growth and multiplication are inhibited, but the bacteria is not killed

Question 25

define disinfection

Answer 25

The process of destroying vegetative pathogens, but not necessarily endospores or viruses Reduce or inhibit growth

Question 26

define bactericidal

Answer 26

kills bacteria

Question 27

Differentiate the functions and purpose of a disinfectant and an antiseptic

Answer 27

Disinfection: Process of destroying vegetative pathogens, but not necessarily endospores or viruses. Chemical applied to object or material Antisepsis: Chemical disinfection of the skin, mucous membranes, or other living tissues

Question 28

Describe what is meant by antimicrobial action

Answer 28

bacteriostatic or bacteriocidal

Question 29

Describe the way each physical agent control the growth of microorganisms

Answer 29

Temperature extremes, including heat and cold: While low temperatures can slow down the growth of microorganisms, heat represents a highly effective method for killing microbes.

Question 30

List the mechanism of action for each type of chemical agent commonly used in antimicrobial reagents

Answer 30

(1) interference with cell wall synthesis (2) inhibition of protein synthesis (3) Interference with nucleic acid synthesis (4) inhibition of a metabolic pathway (5) inhibition of membrane function (6) inhibition of ATP Synthase

Question 31

Differentiate the use and application of skin antiseptics used in a hospital setting

Answer 31

Antiseptics are chemical agents applied to the skin to reduce the microbial count and reduce the risk of surgical site infections

Question 32

Describe the heat methods used for microorganism control

Answer 32

Moist heat sterilization dry heat pasteurization low temperature

Question 33

Describe and differentiate the various types of biological safety cabinets

Answer 33

There are three classes of BSCs: Class I, II and III. While all three classes afford personnel and environmental protection, only Class II and III cabinets provide product protection. Class I BSCs are suitable for work involving low to moderate-risk agents.

Question 34

Quality control in microbiology testing

Answer 34

Quality control involves testing units and determining if they are within the specifications for the final product.