Which ones are DNA- Containing Viruses?
Herpes simplex
Smallpox
Adenoviridae
HPV
Parvoviridae (B-19)
Hepatitis B virus
Hepatitis A virus
Rubella
Ebola Virus
HIV
Viruses are living cells
Which of the following statements are correct?
Viruses can be transferred by mucosal droplets, water, bugs and through the air.
They are living cells
Viruses are bigger than bacteria
They contain special organelles that allow them to self replicate with little to no energy source
Which attributes do viruses have?
Smaller than bacteria
Larger than bacteria
Contains DNA or RNA, never both
Contains DNA and RNA
Few enzymes
Contains many ribosomes
No ribosomes or enzymes for metabolizing nutrients
Contains ribosomes or enzymes for metabolizing nutrients
A virus floats until it finds a suitable host cell. When it does, it unloads "cargo", machinery that allows the virus to take over the host cell 's resources. The virus then uses the resources to produce identical copies of itself. The clones then leave and look for another host cell.
What is a virion?
An infectious viral particle with nucleic acid surrounded by a protein coat
A protein that is essential for the virus to replicate itself.
Another term for a virus
A virus prion
Capsids are _____ that are made of _____ also known as _____
Protein coats; capsomeres; protein molecule
Protein coats; virions; protein molecules
Protein coats; capsomeres; protein chains
Outer coat; capsomeres; virions
What are inserted in envelopes or capsids?
Glycoproteins or spikes
Glyoproteins or glycolipids
Virions or spikes
Virions or glycoproteins
What is a Nucleocapsid?
The complete capsid of a virus.
A capsid that is a part of the nucleus
An incomplete capsid membrane that surrounds the Nucleic acid
They are the complete capsid of a virus made out of nucleic acids
A bacteriophage is a bacterial macrophage, so it eats good cells and digests its nutrients.
HIV is single stranded
If the virus did not take a piece of the original host phospholipid membrane and use that as the membrane, it may form a lipid envelope from the host cells of other cells it has infected
Which of the following statements are not true about bacteriophages?
They are viruses that infect bacterial cells and can transfer new genes from one bacteria to another
They can be used as a tool for genetic engineering
They can transfer genes for the production of a toxin
They have a host range of animal bacteria.
What are the events that occur in viral infections?
1) The viral particles' membrane either fuses with the membrane, leaving the capsid to carry the virus into the cytoplasm of the host cell or the viral particle can cross the host cell membrane by pinocytosis
1) The viral particles' membrane can fuse with the membrane due to its affinity for the viral particles receptors, or it can cross it by binding to the sites due to the tropism (cells affinity) for the viral receptors and then being pinocytosed by the host cell
2) DNA Virus: The virus DNA uses the host cells DNA polymerase to replicate itself in the host cell nucleus. Then is uses DNA-dependent DNA polymerase to replicate its genome DNA->DNA then uses reverse transcriptase DNA->RNA->DNA RNA Virus: Uses its own RNA polymerase and reverse transcriptase. So it uses RNA-dependent RNA polymerase for replication RNA->RNA and then uses reverse transcriptase RNA->DNA
2) DNA Virus: The virus DNA uses the host cells DNA polymerase to replicate itself in the host cell nucleus. Then is uses DNA-dependent DNA polymerase to replicate its genome DNA->DNA then uses reverse transcriptase DNA->RNA->DNA RNA Virus: Uses its own RNA polymerase and uses RNA-dependent RNA polymerase for replication RNA->RNA and then uses reverse transcriptase RNA->DNA->RNA
3) Association of newly replicated RNA or DNA with newly made viral proteins results in new nucleocapsids. If envelope components are produced and inserted into the host cell plasa membrane, the viral particle then attaches to the plasma membrane and buds through, thus forming an enveloped virus.
3) Newly made viral proteins and newly replicated DNA or RNA nucleic acid form new capsids. An enveloped virus can form if a virus forms all of its viral components, then detaches itself from the host cell and looks for a new host cell to infect. When it successfully finds and infects a new host cell, it takes portions of its plasma membrane to form the envelop for the virus.
Which description is not a Host-virus interaction?
Acute or Productive Infection - virus replicates, and produces many virions, the host cell is often killed (lytic infection)
Latent Infection - viral genome persists in host cell but does not replicate "provirus"
Chronic Infection - Virus replicates without causing host cell lysis (cell rupture) and can persist for long periods of time
Persistent Infections - release of viruses does not usually harm the host cell resulting in the host cell producing the virus for long periods of time
What is the difference between chickenpox (acute) and shingles (latent)?
Chickenpox has lesions at different stages while shingles has lesions at the same stages
Chickenpox has lesions at the same stages while shingles has lesions at different stages
Chickenpox has smaller lesions than Shingles
Chickenpox has bigger lesions than Shingles
When viruses "transform" normal host cells to cancer cells these cancer cells are called___
oncogenic viruses
malicious tumour viruses
benign tumour viruses
transformative viruses
Patient specimens added to cultured cells and after a period for growth, observed for cytopathic (CPE) effects on the host cells
Syncytia is a CPE that takes the cells in a tissue and a causes them to fuse together so that the membrane becomes high with multiple nuclei. The virus then takes over and uses all the resources and then the cell dies. A giant hole is left where the cell would've been.
Identify the incorrect description of prions
Can cause protein misfolding disease
Prions are misfolded proteins that act as infectious agents in susceptible animals
Examples: Scrapies, Mad cow disease
Examples: Rabies, SARS
What are the 3 types of parasites?
Protozoa
Metazoa
Ectoparasites
Amoeba
Lymphocytes
Mesazoa
Which statement of protozoans are incorrect?
Some have a "cyst form". In order to protect itself from inhospitable environments., it forms a thicker outer layer or a "cyst"
The growing form in many species called "trophozoite"
Cyst form may also be called an "oocyst" in same types of protozoa
It is a multicellular organisms
Which one is not a protozoan
Entamoeba histolytica
Giardia lamblia
Trichomonas vaginalis
Acanthamoeba
Cryptosporidium
Toxoplasma gondii
Trypanosoma
Leishmania
Plasmodium
Enterobius vermicularis
Nosocomial means it is a hospital acquired infection
Which protozoan has cysts that have a high degree of resistance to chlorine?
Which protozoan causes high amounts of flatulence, and cysts that are hardy and have high resistance to chlorine?
Giardia Lamblia
Schistosoma
Choose the correct statement about Trichomonas vaginalis.
There is no cyst stage, it infects person to person through sexual transmission. It is found in the vagina and male urethra and causes intense itching, inflammation of tissues
They are roundworms with complete digestive system (this includes a mouth, intestine and anus). There are two categories/types; eggs as the infective stage, larva as the infective stage.
It causes malaria and has no current vaccine. There are 4 main types that are transmitted by the mosquito and it carries the sporozoite in the saliva which then enters the blood stream and targets the liver.
It is found in domestic cats' feces as oocysts. If another mammal ingests this protozoan, tissue cysts can form. A human can get it from undercooked meat (tissue cysts) or from contact with cat feces (oocysts)
What are the characteristics of Acanthamoeba sp
Grows in water, exists as cyst form in dust
Often found in the eye (important for contact lens wearers)
Eye loss outcome of infection
Cyst and trophozoite stage in humans
Obligate intracellular parasite
Immunocompromised people can have severe chronic diarrhea while immune-competent people can have serious diarrhea.
high resistance to chlorine
About 20 different species cause this disease, all of which are transmitted by sand flies
No good treatment
Visceral, cutaneous and mucocutaneous syndromes - caused by different species
What is the Growing form in a Protozoan called?
Trophozoite
Oocyst
Cyst
Ulcer
