Exam 2 Flashcards
Which of the following statements is correct?
a. MHC- I on APC
b. MHC- II on all nucleated cells
c. APC have both MHC - I and II
d. All the above are correct
c. APC have both MHC - I and II
True/False. MHC I restricted consist of CD4+ cells and MHC II restricted consists of CD8 + cells.
False. MHC I = CD8+ and MHC II = CD4+
Where are endogenous antigens processed?
Cytosolic pathway bound to MHC I and present on cell surfaces
____ antigens are processed in endosomes bound to MHC II and present on the cell surface.
Exogenous antigens
What are the components of T cells?
CD8+ : cytotoxic
CD4+ : Th1 - cell-mediated immunity and Th2 - humoral immunity
Which cells are considered ADCC?
- NK cells
- Macrophages
- Neutrophils
- Eosinophils
Which diseases are considered parasitic?
a. Taenia Solium
b. Brucellosis
c. Giardia
d. A and B
e. B and C
d. A and B
____ is a virus that enters tissue from saliva when bit by an infected raccoon.
Rabies
Which virus can be transmitted through the saliva, urine, or feces of a rodent?
Hantavirus
What are control and preventative methods of Giardia?
- Water treatment
- Sewage treatment
- Proper washing of fruits and veggies and hands after using the restroom
What parasite is a tapeworm that affects pigs and can form neurocysticercosis in the human brain if the larvae of a cyst is consumed?
Taenia solium
___ is an inhaled spore forming bacteria that can be prevented by burning infected carcasses or burring them in quick lime.
Anthrax
____ is a bacteria that is transmitted through ingestion, mucous membrane exposure, or percutaneous (through skin) inoculation.
Brucellosis
What are the two most pathogenic forms of Brucellosis for people?
Brucella melitensis
Brucella abortus
Which vector borne disease is transmitted through ticks?
Borreliosis
___ is a vector borne disease transmitted by a mosquito –> bird –> mosquito cycle.
West Nile Virus
What is zoonoses?
Infectious diseases that people get from animals either directly or indirectly
About ____ percent of all pathogens in human beings are zoonotic and about __ percent are emerging diseases.
60%, 75% emerging
Which of the following is a disease caused by an agent capable of transmission by direct airborne or indirect routes from an infected person, animal, plant or contaminated reservoir?
a. Communicable
b. Contagious
c. Transmissible
d. Infestation
a. Communicable
Disease transmission is a result of the interaction between the ___, ___, and ___.
Host, agent, and environment
What is a reservoir?
Habitat in which an infectious agent normally lives, grows, and multiplies
Perinatal and transplacental/Transovarial are ____ modes of transmission that are transferred from a reservoir host to its offspring.
Vertical
What are horizontal modes of transmission?
Direct: directly from reservoir to host
Indirect: via an intermediary, animate or inanimate
What are different modes of direct transmission?
Direct contact
Direct projection (droplet spread)
Airborne
___ is an inanimate object which serves as an indirect mode of transmission.
Vehicle
A ____ is an indirect mode of transmission where a living organism serves to communicate disease.
Vector
What are types of vehicles?
- Fomites: object that can be contaminated and transmit disease on a limited scale
- Common vehicle: food, water, contaminated IV drugs
What is a mechanical vector?
Agent that does not multiply or undergo part of its life cycle while in/on the arthropod
What is a biological vector?
Agent that undergoes changes or multiplies while in the vector, which is required for transmission
____ is a previously unknown disease that suddenly appears in a population but can also be a known disease that suddenly appears in a new population.
Emerging
What is re-emerging disease?
Known disease previously on the decline that is becoming more common and will continue to do so.
The probability of transmission from a reservoir to a new host increases with:
- Increase abundance of reservoir
- Increase pathogen prevalence in the reservoir
- Increasing contact between reservoir and new host
Which of the following characteristics do antibodies not have?
a. Consisting of two heavy and two light chains
b. Binding specifically to antigens
c. Recognizing native antigens
d. All classes including IgA activate compliments by classical pathway
d. All classes including IgA activate compliments by classical pathway
True/False. All complement activation pathways have the same C3 convertase.
False.
What is the key product of the classical and alternative pathway?
C3b
Which of the following pertains to C3 convertase of the classical pathway?
a. C4bC2b
b. C3bBb
c. C4bC3b
d. C3bC2b
a. C4bC2b
What is the initial complement component of the classical pathway?
C1 QRS, C4 and C2
What activates the classical pathway?
- Binding of Antibody to antigen
- C1 reactive protein binding
____ is the C5 convertase of the classical pathway.
C4bC2bC3b
Which of the following is false regarding the lectin pathway?
a. Activated by MBL and MASP-2
b. C4 and C2 are the initial complement components
c. C3 convertase is C4bC2b
d. C5 convertase is C4bC3bC3B
d. C5 convertase is C4bC3bC3B
C5 convertase = C4bC2bC3b
Which of the following is false regarding the alternative pathway?
a. Activated when there is contact of the microbial cell wall with C3
b. Initial component is C3, Factor C, Factor F, and Properdin
c. C3 convertase - C3bBb
d. C5 convertase- C3bBbC3b
b. Initial component is C3, Factor C, Factor F, and Properdin
Initial components are C3, Factor B, Factor D, and properdin
True/False. Adaptive immune response are induced by exposure to antigen(s), responding specifically to the induced antigen generating immunological memory.
True
____ immunity is mediated by antibodies secreted by antigen- activated B cell and their progeny plasma cells
Humoral immunity
Which response has a shorter lag phase, grater magnitude, and uses IgG?
Secondary response
What is a paratope?
Part of the antibody that recognizes an antigen, specifically the antigen-binding site of the antibody
What do B-cell receptors and antibodies recognize?
native protein antigens
What is the role of antigens?
- Induce specific, adaptive immune responses
2. React specifically with the products of the response
Where are paratopes found?
Antibodies
B cell receptors
T cell receptors
What are the two components of the complement pathway?
Classical
Alternative
What are the end effects of the compliment pathways?
- Cell lysis
- Inglammation
- Opsonization
- Clearance of immune complexes
_____ immunity is mediated by antigen-activated T cells and the cytokines they secrete.
Cell mediated immunity
True/False. MHC class I is found only on APC’s and MHC class II is found on all nucleated cells, including APC’s.
False.
MHC I = all nucleated cells, including APC’s
MHC II = only APC’s
Which of the following are considered APC’s?
a. B cells
b. Macrophages
c. Dendritic cells
d. All the above
d. All the above
In an exogenous antigen, CD4 with TH1 activates macrophages for _____ and CD8 with TH2 activates B cells for _____.
CD4 with TH1 = macrophage for DTH response
CD8 with TH2 = B cells for antibody response
CD8 T cells are ____ restricted and CD4 T cells are ____ restricted.
MHC I, MHC II
CD8 CTL is an _____ antigen.
Endogenous
High Th2 response and a low Th1 response is a _____ phenotype.
Susceptible
Increased Th1 response and decreased Th2 response is a _____ phenotype.
Resistant
_____ is the study of viruses and viral diseases and ___ is someone who studies viruses.
Virology, Virologist
Are viruses living?
NO
What surrounds the nucleic acid genome of a virus?
Protein coat (capsid) and sometimes a lipid evenlope
True/False. Viruses posses standard cellular organelles such as mitochondria, chloroplasts, Golgi, and ER with associated ribosomes.
False. They do not possess these things!
The following pertain to viruses except:
a. Viruses can make energy and protein by themselves
b. All viruses are obligate intracellular parasites
c. Viruses do not have the genetic capability to multiply by division, reproduction resembles an assembly line
d. Their capsid is made up of capsomeres held together by non-covalent bonds
a. Viruses can make energy and protein by themselves
- They rely on a host to survive
A capsid + Virus Nucleic acid or Genome is called ____.
Nucleocapsid
What is present on the surface of the envelope that resemble spikes?
Glycoproteins
What is a non-eveloped virus that has only protein capsid enclosing nucleic acids?
Naked viruses
What is the term known as the ability of some viruses to alter their shape and size?
Pleomorphism
Virus Replication
Attachment –> Penetration –> Uncoating –> Synthesis of viral nucleic acid and protein –> Assembly and maturation –> Release in large numbers
What impacts does the virus replication have in the host cell?
- Cell Death
- Transformation of cell to Malignant one
- Fusion of cells, Multinucleated
- No apparent changes to infected cell
The _____ is the only body charged by the international union of microbiological societies with the task of developing, refining, and maintaining a universal virus taxonomy.
ICTV
What are the different techniques used to detect a viral antigen or host antibody against viruses (serology)?
ELISA
Fluorescent antibody staining
Immunohistochemical staining
Which of the following are used for the detection of viral nucleic acids?
a. RT-PCR/ PCR
b. Quantitative PCR
c. Virus Genome Sequencing
d. All the above
d. All the above
True/False. Dendritic cells are the best APC’s to activate naive T cells.
True.
What forms holes in the membrane so cells can be lysed?
MAC
____ refers to the ability of a Virus to cause Disease in a host and the virus that causes disease is called a ____
Pathogenicity, Pathogen
Which term refers to the quantitative or relative measure of the degree of pathogenicity of the infecting virus?
Virulence
What are the factors related to the virus?
- Genetic variation of virus
- Route of entry of virus in host
- Affinity of virus to host organs
- Dose of Infection
- Immuno evasion
What factors are related to the host?
- Host species
- Host immunity
- Host physiological factors
- Fever
Ture/False. A lower LD50 means the more virulent the virus.
True
What are routes of entry of a virus into the skin?
- Cut or breach
- Bite of Arthropods
- Bite of an infected animal
- Contaminated objects
Routes of entry of viruses into host mucous membrane
Cunjunctiva
Oropharynx
Genitourinary Tract and Rectum
What are the two ways primary viremia can occur?
- Spread of virus infection to blood from subepithelial tissue/lymphatics
- Directly injected in blood through bite of mosquitoes or syringes
What is secondary viremia?
When the virus has replicated/multiplied in major organs and once more entered the bloodstream
Spread of viruses via nerves
- Through peripheral nerves
- Through receptor neurons in the nasal olfactory epithelium
- Crossing blood brain barrier and infecting CNS
Viruses that infect neural cells are ___ and those that enter the CNS after infecting peripheral sites are ___.
Neurotropic, Neuroinvasive
What are neurovirulent viruses?
Viruses that cause disease of nervous tissue, manifested by neurological symptoms and often death
What is the name for the specificity/affinity of a virus for a particular host tissue?
Tropism
Virus-Cell interactions
- Inhibition of host cell nucleic acid synthesis
- Inhibition of host cell RNA synthesis
- Inhibition of host cell protein synthesis
- Cytopathic effects of “toxic” viral proteins
- Interference with cellular membrane function
True/False. Acute infection can shed at low titers for months to years and persistent infections can intensely shed for a short period of time.
False. Acute = intense shed for short time period
Persistent = lower titers of shed for months to years
What is a wart?
Benign skin growth that appears when a virus infects the top layer of the skin
___ is a fluid filled sac, ___ is an opening in the skin caused by sloughing of necrotic tissue, and ____ is a solid tumorous mass.
Vesicle, Ulcer, Nodule
Aimed at maintaining a healthy population by adopting measures to avoid occurrence of disease by eliminating the pathogen or increasing resistance to disease
Primary prevention of infectious diseases
___ is the process that destroys or eliminates all forms of microbial life/ pathogen and ___ is the application of liquid antimicrobial chemical to skin or living tissue to inhibit or destroy microorganism.
Sterilization, Antisepsis
What are the sterilization methods?
- Moist heat
- Dry heat
- Chemical methods
- Radiation
- Sterile filtration
Chain of infection
Pathogen –> Host reservoir –> route of exit –> mode of transmission –> route of entry –> new susceptible host
____ is when all potentially infected animals or people are treated without first testing them
Mass therapy
____ applies to those who have been exposed to a contagious disease and ____ applies to those who are known to be ill with a contagious disease
Quarantine, Isolation
What is Herd Immunity?
Form of immunity that occurs when the vaccination of a significant/large portion of a population provides a measure of protection for a small number of the individuals who have no developed immunity.
What does WAHID and OIE stand for?
WAHID- World Animal health information database
OIE- World Organization for animal health
The infected zone immediately surrounds the ____and the buffered zone surrounds the ____.
Infected premises, infected zone
Consists of an infected zone and a buffer zone
Control Area
Zone outside and along the border of a control area.
Surveillance zone
What are the collaboration of GLEWS?
FAO: food and agriculture organization of the united nations
OIE: World organization for animal health
WHO: World health organization
