Final Exam Microbiology Flashcards
pathogen
a bacteria, virus, or other microorganism that can cause disease
Who developed the classifying system for naming organisms?
Karl Linneaus
List the parts of the prokaryotic cell
Flagellum (the long tail), Pili (the spike), capsule (1st layer), Cell Wall (2nd Layer), Cell Membrane (3rd Layer), Ribosome (the balls inside), Chromosomal DNA (in the nucleoid-the spiral string)
Bacterial Shapes
- Bacullis: rodlike
- Coccus: spherical
- Spiral: curved/corkscrew
Why are viruses not considered to be living organisms?
They can’t be independent or grow by themselves
What is the infectious agent that causes AIDS?
HIV
Name the Domains
Archae, Bacteria, Eukarya
Who observed the first cells?
Robert Hooke
Who observed the first microorganisms?
Anton van Leeuwenhoek
What was the idea behind spontaneous generation? Who disproved the theory?
until the late 1800’s scientists believed that life came spontaneously from nonliving matter. Louis Pasteur
yeast that converted sugar to alcohol in the absence of air
fermentation
who discovered that microbes cause disease?
Robert Koch
Who was the first to use disinfectant in the wounds?
Joseph Lister
Robert Koch identified the cause of what disease?
tuberculosis, anthrax
Who is the first physician associated with vaccination?
Edward Jenner
What is used to produce antibiotics?
chemicals in the lab aka synthetic drugs
What was the first antibiotic used?
penicillin
What scientist attempted to prove the theory of the “magic bullet”?
Paul Ehrlich
Where are typical microbiota never found?
internal organs, body fluid
Know what color Gram positive and Gram negative bacteria stain
Gram-positive: purple
Gram-negative: pink or red
Know the steps in the Gram stain process
- applying a primary stain (crystal violet). wash off after a short time
- Adding a mordant (Gram’s iodine).
- slide is washed with alcohol
- alcohol is rinsed off and slide is then stained with safranin
- wash off safranin, blot dry, and look under microscope
What is the mordant in Gram staining? What is its purpose?
It’s gram’s iodine and used to make the microorganisms stain more intense
What are the steps in preparing a slide to look at under a microscope?
- Place a small drop of your sample
- Take a second glass slide and hold it at an angle and touch the end of your angled slide to the droplet and wait until the liquid flows along its width.
- Push your angled slide out along the length of the bottom slide in a smooth spreading motion, creating a smear. Try to maintain an even contact and keep the slide at the same angle.
- Leave the slide to dry so that it can be stained or place a coverslip over the smear, depending on what your sample needs.
Simple staining improves contrast in what type of microscope?
Compound Light Microscope
Be able to calculate total magnification of a microscope if given the ocular and objective magnification
objective power x ocular power
Ex: 10x x 40x = 400x
Which stage of Gram staining is critical in differentiating Gram positive from Gram negative?
the length of decolorization
Why are bacterial slides fixed before staining?
to bind the speciment to the slide so that it doesn’t wash off
Ability of the microscope to distinguish two points
resolution
both organisms benefit from one another
symbiotic relationship
infections patients acquire while receiving treatment for othe rconditions at a healthcare facility (HAI) also called
nosocomial infection
What was the major significance of Robert Koch’s work?
Koch’s postulates that tell you a specific disease that is caused by a specific microorganism
Define biological transmission. Define mechanical transmission.
Biological transmission: vector overtakes an agent through a meal from an infected animal
Mechanical transmission: vector transports through other infected organisms to feet, body hair, or other body surfaces
many people in a given area acquire a certain disease in a short period of time
epidemic
disease is constantly present
endemic
worldwide epidemic
pandemic
the number of people in a population who develop a disease during a particular time period, indicated spread of diseases
incidence
disease occurs occasionally
sporadic
when a local infection enters the blood or lymph system and spreads to other parts of the body
focal infection
source of the organisms that cause the disease
reservoir
an infected person transmits an infectious agent, either directly or indirectly, to another person who in turn becomes infected. Give examples
communicable diseases
ex: chickenpox, measles, influenza
objects or materials that are likely to carry infections
fomite
caused by a pathogen after a primary infection has weakened the body’s defenses
secondary infection
define signs and symptoms as they related to disease
signs: objective changes
symptoms: changes in body function like pain
the science that studies when and where the diseases occur and how they are transmitted in populations
epidemiology
What can contribute to postoperative infection?
not washing hands or disinfecting instruments.
the number of people in a population who develop a disease at a specified time
prevalence
the pathogen is inactive for a time but then becomes active to produce symptoms
latent disease
Stages of disease
Incubation: acute disease after the initial entry of the pathogen
Prodromal: the pathogen continues to multiply and the host begins to experience general sings and symptoms of illness
Illness: the signs and symptoms of disease are most obvious, specific, and severe
Decline: the number of pathogens begin to decrease, the sngs and symptoms of illness begin to decline
Convalescence: patient returns to normal
what virus causes warts?
HPV
What is a potential conplication of the chicken pox?
encephalitis or pneumonia
What area of the skin has the most bacteria on it?
hands
What bacteria causes acne?
propionibacterium acnes
Why is the vaccination for rubella recommended?
to prevent it
What symptoms are caused by HSV-1
cold sores
Why was the eradication of smallpox possble?
Since smallpox only effects humans and humans were vaccinated for it, it eventually got eradicated
What are the symptoms of chicken pox?
fever, headache, sore throat
