Question | Answer |
Define normal flora. | Microorganisms that begin to colonize the body at birth. These organisms live ON or IN the body, this being a normal and healthy state, under most circumstances. |
How are microorganisms named? | Genus and species |
Define opportunistic pathogen. | Organism that dos not usually cause disease, but can be pathogenic under certain conditions |
What were the features of a procaryotic cell that were given in your textbook? | Single, circular chromosome
Undergoes cell division by binary fission
Not surrounded by a nuclear envelope.
No tissue/organ structure. |
What were the features of an eukaryotic cell that were given in your textbook? | More than one chromosome
Surrounded by a nuclear envelope.
Chromosomes are arranged in a linear fashion
Undergo cell division by mitotic division. |
Are bacteria prokaryotes or eukaryotes? | Bacteria are prokaryotic organisms. |
Many bacteria possess structures called “plasmids”. What are these structures and what is their function? | Small circular molecules of DNA. They are self-replicating, and code for traits that assist survival in adverse conditions. |
List the three basic bacterial morphologies. | cocci (round), bacilli (rods) helical (spiral) |
The cell walls of bacteria consist of what basic building blocks? | Carbohydrates (sugars), lipids (fats), and proteins |
List the reagents used in a gram stain procedure and their purpose. | Reagents used in the Gram stain technique:
1. crystal violet (primary stain)
2. iodine (mordant—enhances staining)
3. alcohol/acetone (decolorizer)
4. safranin (2nd or counter stain) |
Two types of bacterial cell walls exist. Name them. | Gram Positive (purple) and Gram Negative (pink) |
What is it about the structure of bacterial cell walls that allows the gram stain procedure to stain some organisms gram positive while others stain gram negative? | Amount of lipids (fat) in the cell walls of the microorganisms |
Briefly explain why microorganisms are necessary for life | 1.normal/resident flora protect us from the pathogenic microorganisms. If we did not have these microorganisms colonizing our bodies, we would die
2. Environmental, help to create the environment we live in
3. Used in the food industry (production or |
Why is it necessary to have a quality assurance program in your laboratory? | To ensure quality of patient care. Ensures structured, consistent, and reliable patient outcomes. |
What are the components of a quality assurance program in microbiology? Give a brief explanation of each | Specimen – Organisms should remain unchanged from the patient to laboratory.
Media and reagents – Use controls 2test reliability of media & reagents |
What were the three levels of host-organism interaction given in your textbook | Microbes are capable of the following levels of host-organism interaction:
1. colonization
2. infection
3. disease |
Why do microorganisms have a survival advantage? | They can adapt to new environments quickly due to rapid multiplication |
define microbial pathogenicity | The biochemical mechanism, whereby microorganisms can cause disease |
define pathogen. | Disease causing organism |
define colonization | Persistence of microorganisms in a body without causing disease (i.e. normal flora) |
define infection. | Successful persistence or multiplication of a pathogen on or within a host |
define disease. | Infection that causes overt damage to the host |
define asymptomatic carrier | Infected host, showing no signs of clinical symptoms who is/may be an unknowing source of a disease in a population |
define symbiosis. | Relationship between a host and a microbe |
Give three examples, from your textbook, of symbiotic (host-microbe) relationships and what the relationship means | Mutualistic (both organisms benefit)
Commensal (no harm is done to the host)
Parasitic (microbe benefits at the expense of the host) |
What is meant by the term "zoonoses"? | Animal – to – human transmission |
List the two types of host defense mechanisms that were presented in your textbook. | nonspecific or innate defenses
specific or adaptive immunity. |
List four “innate” defense mechanisms our bodies use to fight off infections | 1. physical and chemical barriers
2. phagocytic leukocytes
3. fever
4. acute inflammation
5. complement cascade
Genetically determined, do not improve with repeated exposure to the infectious agent, but may be more important to survival than acq |
What are the four classic signs of inflammation? | 1) redness 2) heat
3) swelling 4) pain |
Give a brief explanation of what "adaptive resistance" is, and how it accomplishes this task | aka acquired immunity |
What is meant by the term "immunologic memory"? | Recognition of invading microorganisms which have previously been destroyed |
Are we born with adaptive immunity? Explain | Immune system adjusts to the microbes to which they become exposed |