1. Cellular morphologies of bacteria are described as coccoid (round) and bacilliform (rod). Virus particles (virion) also have common shapes, two of which are;
A. Orthogonal and enveloped
B. Enveloped and amorphous
C. Helical and Icosohedral
D. Orthogonal and Icosohedral
C. Helical and Icosohedral
2. The nucleocapsid is best described as;
A. The envelope plus the capsid
B. Binding site for nucleotides on the capsid
C. Capsid and Genome
D. Lipid bilayer nucleus
C. Capsid and genome
3. Which best describes the virion size and nucleic acid content of picornaviruses?
A. DNA genome, very small
B. RNA genome, very small
C. DNA genome, large
D. RNA genome, large
B. RNA, very small (pico-rna)
4. Hepadnaviridae are a group of viruses that have a ________________________ genome and are associated with infection of the________________________.
D. RNA, liver
A. DNA, liver (hepa dna)
5. From a single cell, bacteria multiply (binary fission) resulting in a population of clones on the surface of an agar plate termed a ‘colony’. Analogously, a single virion can infect a single host cell on the surface of a culture plate containing living tissue or cells. Subsequent infection and lysis of neighboring cells results in a clearing termed a ______________________.
C. plaque D. hemozone
6. The ___________________________ assay is a method used to quantify the number of virion in a particular sample, wherein serial dilutions of the sample are mixed with RBC’s in microtiter plates, and ‘button’ results are visible by eye.
A. hemagglutination--I saw it on Google images
7. _____________________ is the term used to describe the process where enveloped virion are released from the host cell.
8. Presence of virion in the _________________ is termed viremia.
9. Reverse transcriptase is an enzyme that converts ____________ into ____________ , a necessity for the retroviridae such as HIV.
A. RNA, DNA
B. DNA, RNA
C. Protein, RNA
D. RNA, protein\
A. RNA to DNA
programmed cell death
cascades caused by enzymes
Phages are the oldest ubiqutious organism on the planet: True or false
10. Positive-strand RNA viruses possess a genome that is just like eukaryotic ______________, enabling instantaneous synthesis of proteins required for self replication.
12. The acquired immune response plays a mayor role in viral infections. true or false
12. Initial binding of virus particle to host cell is most commonly referred to as ______________________.
14. Quantification of virus can be achieved by hemagglutination, plaque formation, and real time PCR. True or False
14. The 3 terms used to describe outcomes of a viral infection are acute, chronic, and _____________.
16. The most effective cellular immune response to viral infection is accomplished by;
A. Natural Killer cells
B. Dendritic cells
I think it's A. Natural Kill
Natural Killer cells have the ability to kill our cells because of the absence of
What is Sporadic?
disease occurs infrequently
What is Endemic?
the disease is constantly present
What is Epidemic?
a sudden increase in the incidence of a disease over the normally expected amount of time
What is Pandemic?
epidemic on more than one continent
Major outer surface (lipo)proteins of Lyme Borrelia while in the Ixodes mudgut.
ospA synthesis is reduced during bloodmeal.
OspA is a trnsmission-blocking Lyme disease vaccine
Crystal structure predicts a binding pocket
OspAB mutant auto-agglutinates
Apparently, experiments prove that OspAB are not midgut adhesins!
Gram negatives in the GI tract-normal flora
E coli adhesion (4)
Type 3 secretion system-
like a syringe-docks into host membrane,
injects receptors tht come up to dock with e. coli
Proteins make a long chain which rises up above host cell
Tells cell to suck it up and modifies cell from the inside.
Injects toxins into host cell
Causes changes in host proteins to induce phagocytosis
produces a profuse inflammatory response with abd pain/diarrhea
no epithileal cell invasion-stuck on luminal surface
Can lead to fever, headache, WBC elevation and sepsis
Salmonella typhii, Tersinia enterocolitica
Enteric Bugs (5)
1. Escherica Coli-prototype
2. Salmonella-facultative intracellular, usually from animal feces
3. Shigella-similar to enterinvasive E. coli
4. Vibrio/cholera-curved with polar flagella.
5. Cholera-death from dehydration/fluid loss
6. Helicobacter-2nd leading cause of duodenal ulcers –acid loving (first cause of ulcers is ASA and chronic gastritis
Where does gas come from?
Many enterics eat lactose and produce acid and gas
Methyline Blue agar
Methyline blue dye inhibits growth of gram + bacteria (selective)
Differentiates Gram- by their ability to ferment lactose (turns media purple/black)
Uses bile salts which inhibit growth of Gram+
differentiates Gram- by their ability to ferment lactose (turns media pink).
What is the most significant structure involved in septic shock?
threadlike and pleomorphic
Differences beween E. coli and Salmonella
E. coli replicates, sticks, releases exotoxins
Salmonella induces phagocytosis, is not normal human flora, gotten from contaminated food
Both affect ability to make actin
Stick to intestinal wall with fimbrae
heat stable, heat labile inhibit NaCl ion absorption
E. coli (9)
Number is antigens
Virulence factors-pili, exterotoxins
Injection of its own receptor into host cell
Hijack host cell actin cytoskeleton assembly
toxin prevents reabsorption of Na,Cl=imbalance in electrolytes
inhibits 60s ribisome in mammals causing decreased protein synthesis and cell death.
Blood in diarrhea
-Shiga toxin-bacteria shuts down our cell synthesis
Indiced cellular uptake (actin)
Hijack khost cell by "in-phagosome" releae of host cell "effector molecules"
culture medium that allows the growth of certain types of organisms, while inhibiting the growth of other organisms- dyes in the medium (e.g.: methylene blue in EMB & crystal violet in MacConkey's) or high salt concentration in the medium (e.g.: 7% salt in MSA) inhibit the growth of unwanted microorganisms
culture medium that allows one to distinguish between or among different microorganisms based on a difference in colony appearance (color, shape,or growth pattern) on the medium.- dyes in the medium (e.g.: eosin/methylene blue in EMB) or pH indicators change the color of the medium as sugars in the medium (e.g.: lactose in EMB & MacConkey's and mannitol in MSA) are fermented to produce acid products
Lysogeny:show up on plate?
No. It's inside the DNA
Enterics-General Stuff (4):
Morphology-Gram negative rods
Virulence factors-antigens, adherence, toxins (see separate question)
Diseases-diarrhea, UTI, septic shock
Enteric Virulence factors (7):
O antigen-polysaccharide on LPS
K antigen-polysaccharide capsule
H antigen flagella
Enterotoxins=exotoxins of enterics
enterotoxigenic T: e coli heat labile toxin, heat stable toxin, and cholera toxin all inhibit reabsorption of Na+ and Cl+, stimulte Cl- and bicarbonate
enterhemmorrhagic- T. shiga and shiga-like toxins inhibit mammalian 60s ribosomes, protein synth, leads to cell death and blood in stool.
Morphology-gram negative Rods
Ecology species specific to a particular mammal
Human diseases-high risk are those who are in contact with meat or contaminated milk products.
infection of skin, conjunctiva, lungs, Gi tract
Can result in blood and organ invasion with Undulant fever.
Aches, chills sweats with a fever that starts in the morning, peaks in the evening.
from body lice-epidemic
Pasturella Multocida (3)
Gram neg cocco-bacillus
Zoonotic organism-likes mouths of dogs and cats
Chlamydia and Rickettsia
Rickettsia are organisms with bacteria and virus like characteristics.
Why won't beta lactams work on Chlamidya?
Because Chlamidya has no peptidoglycan.
Escapes from phagosome and replicates in cytoplasm
primarily infects columnar epithelial cells in mucous membranes--eyes and genitals (rare-lungs)
Painful urination and mucu\oid discharge from urethra
Will not form colonies because it needs to grow in livingcells.
PCR is used to id
Urethritis can progress to cervicitis, PID, sterility, epididymitis and infertility.
Chronic conjunctivitis (10-15 years)
Number 1 cause of preventable blindness in the world
children are main reservior
Rickettsia rickettsii (4)
transmitted by wood and dog ticks in the rocky mountain region
Small rodents to you via ticks
Rocky mountain spotted fever
Proliferation of bbacteria in endotheial cell lining of blood vessels.
Transmitted by human b ody lice to you
Caused Epidemic typhus during wars, overcrowding
1812-1/3 napoleon's army died
WWI-over 3 million deaths
sudden onset and rapid spread of an infection throughout a large population.
when a particular infectious disease exists constantly in a certain population
Rickettsia typhi (3)
transmitted from small mammals to you by fleas
Causes Endemic typhus,
also known as flea borne
Not gram neg or pos
No peptidoglycan (beta lactams ineffective)
single cholesterol-rich membrane (like Us)
Pleomorphic (change) in shape (not coccoid or bacilliform).
#1 cause of pneumonia and bronchitis in teens and young adults
Outer surface protein A
A virulence factor of berillia bergdorferi
causses lyme disease
Half of face paralyzed
detects flourescent antibodies
Does not have to be inside a cell but likes it
Fever starts in AM, peaks in evening.
doesn't have to be inside a cell but likes it.
Chlamidya, Rickettsia (4)
like bacteria and virus
Small, need host cell
Chlamidya replication begins with inhibition of phagosomal fusion
Rickettsia replication escape from phagosome using an actin tail.
Chlamidya has no peptidoglycan so beta-lactams won't work
Chlamidiya won't grow colonies because it needs to live inside a cell
separate proteins according to their electrophoretic mobility
Chlamidya life cycle
EB -elementary body-spore inactive form-has to get into a cell
RB-reticular body-metabolic-uses our ATP too replicate.
lowercase is gene, uppercase is protein
Between animals with vectors
Marburg is related
Infection Results in Lymphocyte Apotosis!
They cause hemorrhagic fever in humans which is characterized by bleeding disorders, high fever, shock and death
Treatment of viruses:
Natural Killer Cells:
Passive transfer of Neutralizing antibodies
vaccines to generate neutralizing antibodies
treatment with viruses
Reoviruses for treating cancer.
Ascaris Worms (4):
Cause the Disease Ascariasis (AKA WIMB)
Weight loss, stomach pain, and WORMS IN MY BUTT
DON't eat the DIRT: it has Ascaris eggs
they mate in mammalian colon
cause human MENINGITIS
Meningitis with HIGH eosinophils, Hemmorhage, brain swelling, COMA and death,
Pinworms and Threadworms
Scotch Tape test
Difficulty sleeping due to Anal itching, bloody stool (esp in children)
Direct contact with human
Chicken pox lesions trunk
Invade Intestinal tract and brain
Infestation of the Digestive tract Can lead to ???
WORLD LEADING CAUSE OF Epileptic seizures due to Infection of BRAIN
Eating Infected Beef or Pork with CYSTS
are blood sucking intestinal parasites
Feet or scratch to blood to lungs to alveoli to pharynx
and THEN are swallowed,
and to the small intestine, where they attach and live 1-2 years on our blood.
Walking bare foot on infected dog and cat doo, cat scratch.
Most complex virus in a brick shaped box
Family of pox
Filarial worms cause filariasis
Transmitted by Mosquito bite and TROPISM for Lymphatic system and Lungs
lay eggs in mammals like horses and humans
Maggots in My HEAD!
Black flies transmit Oncacerceriasis worms
Screw Worms are Maggots of Screw Flies
Shiny green-blue body
Flies lay eggs in open wounds, that hatch in 12 hrs into maggots then drop off and molt into flies and continue the cycle.
Males are sex maniacs
Females mate only once.
Store sperm and look for open wounds.
infected sandfly bites
Protozoan parasite infects RBC's, and then other 'viscera' (spleen, liver) causes anemia
(Sandflies also transmit Bartonella bacilliformis, the grant)