Viral Life Cycle and Diseases Quiz

A virus can gain entry into a host cell through direct fusion with the cell membrane or by being engulfed into a vesicle through endocytosis.

The uncoating phase is when the virus releases its genetic material from its protective protein coat (capsid) after entering the host cell.

During the eclipse phase, the virus's genetic material is replicated and viral components are synthesized, but new virus particles are not yet assembled or released.

<p>Viruses utilize the host cell's machinery to replicate their genetic material and produce viral proteins by hijacking cellular enzymes and ribosomes.</p> Signup and view all the answers

<p>Viral assembly is significant as it involves the formation of new virus particles, or virions, from newly synthesized genetic material and proteins.</p> Signup and view all the answers

<p>Newly formed virions can be released through cell lysis (bursting of the cell) or budding, where virus particles are released gradually without killing the cell.</p> Signup and view all the answers

<p>A virus envelope is a membranous outer layer derived from the host cell's membrane, surrounding the capsid during viral replication or budding.</p> Signup and view all the answers

<p>The viral envelope can make enveloped viruses more vulnerable to environmental conditions like heat and drying, affecting their stability and infectivity.</p> Signup and view all the answers

<p>Rinderpest outbreaks led to widespread famine and social upheaval, significantly affecting agriculture and food security, especially in cattle-rearing regions.</p> Signup and view all the answers

<p>The eradication of rinderpest, achieved through international efforts, is a major milestone in veterinary medicine and public health, marking the disease's last known case in 2003.</p> Signup and view all the answers

<p>Prevention and control of rinderpest involve vaccinating susceptible animals, enforcing strict quarantine measures, conducting surveillance, and enabling rapid response to outbreaks.</p> Signup and view all the answers

<p>Infected birds may exhibit respiratory symptoms such as coughing and difficulty breathing, along with neurological signs like paralysis and tremors.</p> Signup and view all the answers

<p>Newcastle disease virus can lead to a temporary decrease in egg production and may cause hens to lay eggs with abnormal shells.</p> Signup and view all the answers

<p>Morbidity and mortality rates are influenced by the strain of the virus and the age and species of the affected birds.</p> Signup and view all the answers

<p>The virus spreads rapidly through direct contact with infected birds and via contaminated feed, water, equipment, and fomites.</p> Signup and view all the answers

<p>While primarily affecting birds, some strains of Newcastle disease virus have the potential to infect humans.</p> Signup and view all the answers

<p>Mature viruses are primarily released through mechanisms such as cell lysis, budding from the host cell membrane, or exocytosis.</p> Signup and view all the answers

<p>Virus receptors determine the host range by dictating whether a species can express the necessary receptor for viral attachment.</p> Signup and view all the answers

<p>Virus co-receptors enhance viral binding and aid in viral fusion and entry into the host cell.</p> Signup and view all the answers

<p>Endocytosis is a cellular process where viruses exploit the host cell's ability to engulf extracellular materials by forming vesicles.</p> Signup and view all the answers

<p>Specific virus receptors on respiratory epithelial cells determine the tropism of viruses, allowing them to target and infect these cells effectively.</p> Signup and view all the answers

<p>CD4 is an example of a virus receptor associated with HIV.</p> Signup and view all the answers

<p>Viral tropism determines which cell types a virus can infect, influencing the spread and impact of the infection within a host.</p> Signup and view all the answers

<p>The interaction enhances the efficiency of viral entry by promoting conformational changes in viral surface proteins.</p> Signup and view all the answers

<p>Necroptosis is a regulated form of cell death that occurs independently of caspases, characterized by cellular swelling, plasma membrane rupture, and release of intracellular contents.</p> Signup and view all the answers

<p>RIP3 and MLKL are the key proteins involved in mediating necroptosis.</p> Signup and view all the answers

<p>Virus diagnostics are crucial for early detection, management, treatment, and infection control of viral infections in veterinary patients.</p> Signup and view all the answers

<p>Early detection allows for timely treatment initiation and implementation of infection control measures to prevent virus spread.</p> Signup and view all the answers

<p>Virus diagnostics inform the selection of appropriate treatment approaches like antiviral medications, supportive care, or vaccination.</p> Signup and view all the answers

<p>They enable rapid identification of viral pathogens, facilitating timely infection control measures like isolation and vaccination campaigns.</p> Signup and view all the answers

<p>Virus diagnostics provide essential data for surveillance and monitoring of viral diseases at local, national, and global levels.</p> Signup and view all the answers

<p>During necroptosis, there is swelling of organelles and the cell, rupture of the plasma membrane, and resulting cell lysis.</p> Signup and view all the answers

<p>Biting midges (Culicoides spp.)</p> Signup and view all the answers

<p>Arthrogryposis, hydranencephaly, and brachygnathia.</p> Signup and view all the answers

<p>Fever, decreased milk production, diarrhea, and reproductive disorders.</p> Signup and view all the answers

<p>No, Schmallenberg virus did not pose a zoonotic threat.</p> Signup and view all the answers

<p>A sheep vaccine.</p> Signup and view all the answers

<p>Experimental infections of healthy animals with the virus.</p> Signup and view all the answers

<p>Vertically from infected pregnant animals to their offspring.</p> Signup and view all the answers

<p>Germany and the Netherlands.</p> Signup and view all the answers

<p>The initial step in the PCR process is denaturation, which typically occurs at around 94-98°C.</p> Signup and view all the answers

<p>Primers are short, single-stranded DNA oligonucleotides designed to flank the target DNA sequence for amplification.</p> Signup and view all the answers

<p>The temperature is raised to around 72°C to optimize the activity of DNA polymerase for synthesizing new DNA strands.</p> Signup and view all the answers

<p>qPCR uses specific primers and fluorescent probes to detect and quantify the amount of viral nucleic acids amplified.</p> Signup and view all the answers

<p>In RT-qPCR, viral RNA is first reverse transcribed into complementary DNA (cDNA).</p> Signup and view all the answers

<p>Typically, 20-40 cycles are performed in PCR to exponentially amplify the target DNA sequence.</p> Signup and view all the answers

<p>The presence of DNA can be detected using agarose gel electrophoresis.</p> Signup and view all the answers

<p>Knowing the viral sequence is essential to design specific primers for amplifying the target DNA segment.</p> Signup and view all the answers