Exam Flashcards
- Which of the following is a true statement for viruses?
a. Enveloped viruses include ribosomes
b. A viral envelope only includes virus encoded proteins
c. The viral genome can be either RNA or DNA
d. Their capsomeres are made up of capsid subunits
e. They typically have spherical shapes because it is the most stable biological morphology
c. The viral genome can be either RNA or DNA
- Which of the following viruses has a distinctive stellate nucleocapsid morphology?
a. Alphavirus
b. Adenovirus
c. Arenavirus
d. Astrovirus
e. Coronavirus
d. Astrovirus
- An envelope is found in which of the following viruses?
a. Influenzavirus
b. Papillomavirus
c. Parvovirus
d. Adenovirus
e. Circovirus
a. Influenzavirus
- A single Streptococcus is approximately how many times larger than the smallest virus pathogens (Parvovirus and Circovirus)?
a. 10 times
b. 20 times
c. 50 times
d. 500 times
e. 1000 times
Answer is 100 ish (c)
- Viral haemagglutination is a feature of which phenomenon?
a. Virus-antibody complexes binding to complement receptors on erythrocytes.
b. Virus attachment proteins binding to erythrocyte surface antigens.
c. Membrane attack complexes triggered by virally induced complement activation.
d. Toll-like receptors non-specifically reacting to virus envelope proteins.
e. Viral induced fusion of erythrocyte cytoplasmic membranes.
b. Virus attachment proteins binding to erythrocyte surface antigens.
- Which of the following are recognised characteristics of prion proteins?
a. They are resistant to formalin.
b. They are inactivated by autoclaving.
c. They are susceptible to proteases.
d. Their alpha-helix morphology gives them their strength.
e. The genetic origins are transmissible.
A
- Which of the following diseases is caused by a virus?
a. Kuru
b. Scrapie
c. Creutzfeld-Jakob Disease (CJD)
d. Canine Distemper
e. Bovine Spongiform Encephalopathy (BSE)
d. Canine Distemper
- Which of the following viruses is more likely to cause intranuclear inclusions?
a. Adenovirus
b. Picornavirus
c. Paramyxovirus
d. Reovirus
e. Calicivirus
a. Adenovirus
DS DNA enveloped
- Influenzaviruses have which following characteristics?
a. They are non-enveloped
b. They have a genome of positive sense RNA
c. They carry viral-encoded RNA-dependent RNA polymerase in the virion.
d. They use reverse transcriptase to replicate.
e. They replicate in the nucleus.
e and c
- Which of the following is correct for Retrovirus replication?
a. The viral genome is inserted into the host DNA via the action of integrase.
b. Reverse transcriptase first makes an RNA strand copy of the viral genome following uncoating.
c. The virion must carry its own RNA-dependent RNA polymerase
d. Viral encoded protease cuts the host DNA for virus genome insertion.
e. The insertion of viral genome in host DNA is site specific.
a. The viral genome is inserted into the host DNA via the action of integrase.
- Which of the following is an example of a severe disease caused by spillover into an aberrant host?
a. Malignant catarrhal fever caused by Ovine herpesvirus-2
b. Rabies
c. A cockatoo with psittacine beak and feather disease
d. Swine flu
e. Mucosal Disease in cattle
a
- Which of the following events is most likely to occur in a bovine foetus infected transplacentally at age 200 days gestation?
a. Seroconversion
b. Persistent infection and immunotolerance
c. Abortion
d. Congenital anomalies
e. Mucosal disease later in life
A
- Which of the following is a recognised viral mechanism of neoplasia?
a. Papillomavirus E7 protein preventing apoptosis by inactivating P53.
b. The MEQ gene of Marek’s disease virus mimics transcription factors that activate cell replicaiton.
c. Insertional mutagenesis due to herpesvirus infection.
d. Slowly-transforming retrovirus genome random insertion inside or near a tumour suppressor gene.
e. Papillomavirus E7 protein inactivating cellular proto-oncogenes.
B
- Hemagglutinins of Influenzavirus:
a. bind to sialic acid on the surface of epithelial cells which leads to viral entry via endocytosis
b. are nucleocapsid proteins used for host attachment.
c. are enzymes within the envelope that degrade sialic acid in cell membranes.
d. breakdown cell membranes
e. bind non-specifically to all erythrocytes.
A
- Antigenic shift:
a. occurs when two different strains of the same virus combine to form a new virus that has a mixture of genes from the original viruses.
b. can arise from a spontaneous point mutation of individual nucleic acid bases in the viral genome.
c. cannot occur as a result of recombination.
d. only occurs in RNA viruses (such as Rotavirus).
e. is the way canine parvovirus came into existence.
a. occurs when two different strains of the same virus combine to form a new virus that has a mixture of genes from the original viruses.
- Foot-and-Mouth Disease virus:
a. replicates in and lyses epithelial cells of the stratum spongiosum of stratified squamous mucosa and skin and results in formation of vesicles
b. is more common in sheep and goats compared to cattle and pigs.
c. never uses leukocyte trafficking to spread systemically
d. is caused by Vesiculovirus, an enveloped RNA virus
e. is a major cause of economic loss in Australian beef herds.
a. replicates in and lyses epithelial cells of the stratum spongiosum of stratified squamous mucosa and skin and results in formation of vesicles
- Parvovirus:
a. involves infection of mitotically active cells because it requires a target cell-derived duplex transcription template (only available during S phase).
b. is a genus of enveloped DNA viruses that cause lysis of crypt epithelial cells and lymphocytes.
c. is able to turn on DNA synthesis in target cells
d. infection in the dog requires capsid proteins to bind to neuraminic acid and transferrin receptors on the target cell
e. causes similar disease to canine enteric coronavirus but is less severe
a. involves infection of mitotically active cells because it requires a target cell-derived duplex transcription template (only available during S phase).
- IgE mediated degranulation of mast cells is a key effector mechanism of which of the following inflammatory events?
a. Type I hypersensitivity
b. Delayed type hypersensitivity
c. Drug induced anaphylaxis
d. Type II hypersensitivity
e. Type III hypersensitivity
A
- Preformed intracytoplasmic granules present within mast cells contain:
a. histamine, heparin and tryptase.
b. leukotriene-D4 and prostaglandin-D2
c. TNF-alpha and IL-4
d. epinephrine and eotaxin.
e. chemokines and platelet activating factor (PAF)
A
- Desensitisation to Type I hypersensitivity involves which of the following mechanisms?
a. Stimulation of dendritic cells as the dominant antigen presenting cell (APC).
b. Activation of macrophages to produce IL-12 and present antigens to CD4 lymphocytes.
c. Production of IL-5 by CD4 TH2 lymphocytes.
d. Corticosterone induced suppression of CD4 lymphocytes.
e. Exclusion of the antigen from the diet or environment
b. Activation of macrophages to produce IL-12 and present antigens to CD4 lymphocytes.
- Which of the following is a characteristic of Type II hypersensitivity?
a. It is the main mechanism for most allergic skin diseases.
b. It is also known as antibody dependent cytotoxicity.
c. It involves exposure to milligrams amounts of foreign antigen(s).
d. It involves activation of complement via the alternate pathway.
e. It is usually triggered by exposure to environmental haptens or antigens
b. It is also known as antibody dependent cytotoxicity.
- Which of the following is an example of a Type IV hypersensitivity?
a. Myasthenia gravis.
b. Pemphigus foliaceus.
c. Neonatal isoerythrolysis
d. Tuberculin reaction
e. Glomerulonephritis
d. Tuberculin reaction
- In older animals which of the following is a recognised feature of immunosenescence?
a. There is a random deletion of CD4 lymphocytes
b. Phagocytes increase in number to counteract a decline in lymphocytes.
c. Response to vaccination is usually still strong.
d. There is an increase in CD4:CD8 lymphocyte ratio
e. There is diminished self-renewal capacity of haematopoietic stem cells.
e. There is diminished self-renewal capacity of haematopoietic stem cells.
- Severe Combined Immune Deficiency (SCID) in Arabian foals has which of the following features?
a. There is partial failure of adaptive immune responses.
b. Antibody response is retained.
c. Defective Ig gene results in loss of B and T cell receptors.
d. They can be diagnosed at age 1 week by measuring plasma IgG.
e. Haematology at 1 week of age reveals an absence of circulating lymphocytes (absolute lymphocytopaenia).
c. Defective Ig gene results in loss of B and T cell receptors.
- Chédiak-Higashi Syndrome results in:
a. Normal CD8+ cytotoxicity & NK functions but impaired B-cells.
b. Failure of phagolysosome formation in neutrophils and macrophages.
c. Failure of phagocytosis by neutrophils.
d. Normal circulating neutrophil numbers but abnormal neutrophil granules.
e. A defective adaptive immune system due to a defective immunoglobin gene.
B
- Which of the following is the most common pathological mechanism of myasthenia gravis?
a. Type II hypersensitivity directed against nicotinic acetylcholine receptors.
b. Type II hypersensitivity to presynaptic muscarinic acetylcholine choline receptors of somatic neurons.
c. Type I hypersensitivity to sarcolemmal nicotinic acetylocholine receptors.
d. Immunoglobulin M directed against sarcolemmal acetylcholine receptors.
a. Type II hypersensitivity directed against nicotinic acetylcholine receptors.
- Which of the following protects spermatozoa from autoimmune attack in the testis?
a. High background levels of IL-1a, Il-6 and TGF-? and Activin-A in the testis.
b. Immune tolerance generated by Hassall’s corpuscles during thymus development.
c. Low expression of MHC-I by spermatogonia.
d. Down-regulation of IL-17 by spermatogonia and spermatocytes.
a. High background levels of IL-1a, Il-6 and TGF-b and Activin-A in the testis.
- Which of the following are characteristics of the tuberculin reaction?
a. Nodular accumulations of CD4 T cells and epithelioid macrophages.
b. Nodular infiltrations dominated by cytotoxic T cells expressing Fas on their surface.
c. There is a dominance of macrophages producing IL-12 as the chief antigen presenting cell.
d. It is an example of a combined exaggerated TH1, TH17 and TH2 response.
A
- Which of the following are a characteristic of a type III hypersensitivity?
a. Large amounts of IgG or IgM are involved.
b. They involve interactions with IgE bound to mast cells and basophils.
c. Cytotoxic antibody bound to target cells activates complement.
d. They are the result of an exaggerated TH17 response.
a. Large amounts of IgG or IgM are involved.
- Which of the following are key features of systemic anaphylaxis?
a. They can be triggered by exposure to anatomically sequestered host antigens.
b. They only occur after pre-sensitisation to protein antigens, hormones, or drugs.
c. They occur less frequently in atopic animals.
d. They are only triggered by foreign antigens and haptens.
b. They only occur after pre-sensitisation to protein antigens, hormones, or drugs.
- Which of the following is a virulence mechanism of Toxoplasma gondii that results in altered predator aversion in infected mammals?
a. Histone-lysine acetylation in cortical astrocytes.
b. The perpetual, prolonged, periodic, process of cysts rupturing and re-encysting in cortical astrocytes.
c. Decreased glutamate synthesis by astrocytes in the medial amygdala.
d. Epigenetic hypermethylation of arginine vasopressin-related genes in the medial amygdala.
d. Epigenetic hypermethylation of arginine vasopressin-related genes in the medial amygdala.
- The Rb protein discovered in retinoblastomas is an example of:
a. a tumour suppressor gene.
b. a cellular proto-oncogene.
c. A cyclin controlled transcription factor
d. An essential promotor of cell-cycle replication.
e. An important control of G2-M phase progression.
A
- The threshold effect with respect to mutations in mitochondrial DNA is mainly due to:
a. Each mitochondrion contains thousands of copies of mtDNA.
b. There are less than 50 functional mtDNA genes.
c. Heteroplasmic distribution of mtDNA genomes within individual cells.
d. Dilution of lethal mutations due to intracytoplasmic mtDNA sharing.
e. Only maternal mitochondria are inherited.
A
- Ultraviolet light damages DNA by inducing which of the following:
a. Dimerisation of neighbouring pyrimidine molecules in DNA
b. Deletion of nucleotides in DNA
c. DNA strand breaks
d. Balanced inversions of DNA segments
a. Dimerisation of neighbouring pyrimidine molecules in DNA
- Which of the following changes in cell physiology is a hallmark of cancer cells.
a. Metabolic switching to aerobic glycolysis.
b. Upregulated BCL2 gene expression.
c. Inactivation of inhibitory signal receptors.
d. Upregulation of growth signal receptors.
B
- Which of the following characteristics has features best aligned with that of benign tumours?
a. Gastropancreatic choristoma.
b. Ovarian cystic teratoma.
c. Seminoma.
d. Mesothelioma.
B
- Which of the following developmental disorders has the correct definition?
a. Palatoschisis refers to a cleft lip
b. Cheiloschisis refers to cleft palate.
c. Hypospadiasis refers to urethral non fusion
d. Micromelia refers to absence of a limb.
e. Trichoglossia refers to ocular choristomas producing hair
c. Hypospadiasis refers to urethral non fusion
- Which of the following is a characteristic of a primary tumour measuring approximately 1 gram?
a. It has likely undergone 30 cell doublings and reached a population of 109 cells.
b. The emerging dominant cell type has already outmanoeuvred immune surveillance.
c. It must start to secrete angiogenic factors to continue local growth.
d. It is almost always genetically polyclonal by this stage.
A
- Which of the following is a characteristic of p53?
a. Elephants have 20 copies of p53.
b. If minor DNA damage is detected it upregulates BAX which permeablises mitochondrial membranes.
c. Mutations in p53 are usually recognised by their autosomal dominant expression.
d. Two functional copies are necessary for normal cell division.
B
- Which of the following is a recognised viral mechanism of neoplasia?
a. Papillomavirus E7 protein preventing apoptosis by inactivating P53.
b. The MEQ gene of Marek’s disease virus mimics transcription factors that activate cell replication.
c. Insertional mutagenesis due to herpesvirus infection.
d. Slowly-transforming retrovirus genome random insertion inside or near a tumour suppressor gene.
e. Papillomavirus E7 protein inactivating cellular proto-oncogenes.
B
- Which of the following is an example of a viral neoplastic mechanism via altered cell cycle regulation?
a. Papillomavirus E7 protein inactivates Rb.
b. Marek’s disease virus Meq binds and inactivates P53.
c. Polyomavirus T protein binds and inactivates P53.
d. Somatic insertion of the long terminal repeat (LTR) sequences of Retinoblastoma virus upstream to cellular oncogenes.
a. Papillomavirus E7 protein inactivates Rb.
- Which of the following is an example of malignant neoplasia?
a. Lymphocytic leukaemia
b. Fibroma
c. Trichoepithelioma
d. Trichoblastoma
e. Meningioma
a. Lymphocytic leukaemia
- Which of the following is correct for the vast majority of sex-linked genetic disorders.
a. They are all X-linked.
b. They usually result in congenital developmental disorders.
c. They are all recessive.
d. They only affect phenotypical males.
e. They involve mutations of mitochondrial genes.
B
- Which of the following is the closest analogue to the Marek’s disease virus Meq oncogene?
a. Cellular Jun/Fos transcriptional activators.
b. The cellular cyclin dependent kinase (CDK) family.
c. Polyomavirus T protein.
d. Papillomavirus E7 protein.
A
- Which of the following is the most important cell cycle checkpoints susceptible to cancer-associated mutations?
a. The G1/S transition.
b. The G2/M transition.
c. Both the S/G2 and MG1 transitions.
d. The M/G0 escape pathway of stable cells.
a. The G1/S transition.
- Which of the following is the primary carcinogenic mechanism of bracken fern (Pteridium sp).
a. Ptaquiloside is a potent DNA alkylating agent.
b. The plant contained high concentrations of alkylate agent chlormethine which binds and damages DNA.
c. The plant contains the highly reactive and electrophilic molecule dimethyl sulfate.
d. Metabolic activation of ptaquiloside by hepatic cytochrome P450 oxygenase pathways.
A
- Which of the following is true for neoplastic transformations caused by retroviruses?
a. Acutely transforming retroviruses tend to cause polyclonal neoplasms.
b. Lymphocytes are the main target because there are more of these cells in the body.
c. Slowly transforming retroviruses tend to induce polyclonal neoplasms.
d. The tax gene of HTLV-1 stimulates transcription of viral RNA from the 5’ LTR.
a. Acutely transforming retroviruses tend to cause polyclonal neoplasms.
- Which of the following statements is correct with respect to ultraviolet radiation as an important physical cause of neoplasia?
a. It causes pyrimidine dimerization in DNA and therefore errors in transcription.
b. UVB (290-320 nm) is completely absorbed by melanin.
c. It is mainly due to 200-280 nm UVC from sunlight.
d. Long term exposure results in damage to the XPA gene and faulty nucleotide excision repair processes.
a. It causes pyrimidine dimerization in DNA and therefore errors in transcription.
- Which of the following is a characteristic of equine sarcoids?
a. They are associated with Bovine papillomavirus types 1 and 2.
b. They are associated with Equine papillomavirus 1 and 2.
c. They are associated with Equine herpesvirus 5.
d. The lesions are confined to sites of skin injury.
A
- Which of the following cellular events occurs as a result of cyanide poisoning?
a. Blockade of mitochondrial cytochrome oxidase and reduced oxidative phosphorylation.
b. Destruction of sulfhydryl groups of cell membrane proteins.
c. Upregulation of the unfolded protein response due to impaired glycosylation pathways.
d. Down-regulation of the BCL-2 regulatory pathways.
e. Cessation of DNA synthesis and arrested mitoses.
A
- Lipofuscin in liver is a tell-tale sign of which one of the following?
a. Oxidation of tyrosine
b. Systemic overload of iron
c. Free radical injury and lipid peroxidation
d. Vitamin D intoxication
e. Vitamin E deficiency
c. Free radical injury and lipid peroxidation
- Which of the following is an example of proteolipoid proteinosis?
a. Neuronal ceroid lipofuscinoses.
b. Niemann-Pick Disease.
c. Pompe’s disease.
d. Swainsonine poisoning.
e. Haemochromatosis
A
- Which of the following statements best summarises the mechanism of nitrite poisoning?
a. NO2 oxidises ferrous iron Fe2+ to ferric Fe3+ in haemoglobin.
b. It binds to haemoglobin forming carboxyhaemoglobin which is a cherry-red colour.
c. It causes histotoxic hypoxia by interfering with mitochondrial and cellular respiration.
d. It is first converted to nitrate by intestinal bacteria which is then absorbed into the portal circulation.
a. NO2 oxidises ferrous iron Fe2+ to ferric Fe3+ in haemoglobin.
- Which of the following molecules can be absorbed across the bladder wall and thus contribute to toxic recycling in dogs?
a. Certain methylxanthines such as threobromine and caffeine.
b. Chorophenols and Dinitrophenols
c. Dipyridyl herbicides.
d. Cyanogenic glycosides such as amygdalin.
a. Certain methylxanthines such as threobromine and caffeine.
- Cytochrome P-450 system is primarily located:
a. in the endoplasmic reticulum (microsomes).
b. free in the cytosol.
c. in the nucleus.
d. in peroxisomes.
a. in the endoplasmic reticulum (microsomes).
EHV-1 infection in horse persists for?
a. 3-10 days
b. 3 weeks
c. 3-5 months
d. Forever
D. Forever
What process does NS1 protein undergo to cause parvovirus infection?
a. Cleavage
b. Phosphorylation
c. Oxidation
d. Mitosis
e. Hydrolysation
B. Phosphorylation
How Bovine Pestivirus is Transmitted?
a. Horizontally
b. Vertically
c. Aerosol
d. Vector
e. Both a and b
e. A and B
Canine adenovirus; what is the type of protein early transcription results in?
a. Viral Polymerase
b. Capsid
c. Whole virion
d. Ribosome
a. Viral Polymerase
What genetic material does herpes simplex have ?
a. ssRNA
b. ssDNA
c. dsDNA
e. dsRNA
c. dsDNA
Swine Pox enveloped or non enveloped ?
a. Enveloped
b. Nonenveloped
c. IDK
a. Enveloped
Bovine Pestivirus belong to the following family
a. Picornaviridae
b. Flavyviridae
c. Coronaviridae
d. Togaviridae
b. Flaviviridae
What order does the life stages of canine adenovirus occur in
a. Attachment-Internalisation-uncoating-replication-assembly-exit by cell lysis
b. Internalisation-Attachment-uncoating-replication-assembly-exit by cell lysis
c. Attachment-Internalisation-uncoating-replication-assembly-exit by budding
d. Attachment-uncoating-Internalisation-replication-assembly-exit by cell lysis
a. Attachment-Internalisation-uncoating-replication-assembly-exit by cell lysis
EHV1 is transmitted by:
a. Horizontal
b. Vertical
c. Vector
d. Fomite
a. horizontal
b. vertical
d. fomites
How to lesions develop in swine pox?
a. Intranuclear inclusion bodies
b. Intra-cytoplasmic inclusion bodies
c. intercellular inclusion bodies
b. Intracytoplasmic
Which of the following is true
a. EHV cannot cause late term abortion
b. EHV is non-enveloped
c. EHV is a dna virus
d. EHV never causes fever
c. EHV is DNA virus
What is the type of protein early transcription results in? Viral polymerase Capsid Whole virion Ribosomes
Viral polymerase
What process must the NS1 protein undergo to cause disease in dogs with parvovirus?
a. Phosphorylation
b. Mitosis
c. Oxidation
d. Meiosis
A
