General Quiz On Virus: Trivia Questions

Hemagglutination is the term used to describe the agglutination or clumping of red blood cells (RBCs) when they are added to cell cultures. This phenomenon is commonly observed in certain viral infections, where the viruses can bind to the surface of RBCs and cause them to clump together. Hemagglutination is often used as a diagnostic test to detect the presence of certain viruses, such as influenza, and can also be used to study the immune response to viral infections.

The correct answer is "Visible modifications of infected cells". Cytopathic effect refers to the visible changes that occur in cells when they are infected by a virus. These changes can include cell rounding, cell detachment, cell fusion, formation of syncytia, and cell death. By observing these visible modifications, scientists can determine if a virus is present and causing an infection. The other options provided in the question are not related to cytopathic effect and do not provide evidence of viral illness.

The third method of detecting viruses in a clinical specimen is through direct detection of viral antigens. This involves identifying specific proteins or molecules that are unique to the virus being tested for. By looking for these viral antigens, healthcare professionals can confirm the presence of the virus in the specimen. This method is commonly used in diagnostic tests such as enzyme-linked immunosorbent assays (ELISAs) or immunofluorescence assays (IFAs) to quickly and accurately detect viral infections.

Viruses are characterized by their dependency on living cells for replication and cannot grow in artificial media, or only to a limited extent. They multiply by synthesizing nucleic acid and proteins, which are then assembled to form new viruses. Additionally, viruses vary in size, typically ranging from 10 nm to 300 nm.

A virus consists of two main components: a nucleic acid core that carries the genetic code and a protein coat. The nucleic acid core contains the genetic material of the virus, which can be either DNA or RNA. This genetic material is responsible for the replication and production of new viruses. The protein coat, also known as the capsid, surrounds and protects the nucleic acid core. Additionally, the protein coat may also carry antigens, which are substances that trigger an immune response in the host organism.

The correct answer provides a clear and concise explanation of the 5 steps of virus replication (multiplication). It outlines the process starting with the virus adsorbing to receptors on the cell surface, followed by the virus entering the cell and releasing its nucleic acid. The viral nucleic acid then redirects the cell metabolism to produce viral protein and nucleic acid. The viral components are then assembled to form mature virus particles, and finally, the newly formed virus particles are released through either cell lysis or budding through the cell membrane.

The two main approaches to viral diagnosis are the detection of viruses in clinical specimens and the detection of the patient's immune response triggered by the virus, specifically the detection of antibodies in the patient's blood.

The correct answer is A) Visualization by Electron microscopy: since viruses are extremely small. This method involves using an electron microscope to directly visualize the virus particles in a clinical specimen. Since viruses are too small to be seen with a light microscope, electron microscopy is necessary to observe their structure and identify them. This technique allows for the direct detection and identification of viruses in clinical specimens.

The question asks for three methods that can be used to detect viruses based on the effects they have on cell cultures. The first method mentioned is cytopathetic effects, which refers to visible modifications in infected cells. This means that when a virus infects a cell culture, it causes noticeable changes in the appearance or behavior of the cells. The second method is haemagglutination, which involves the ability of viruses to cause red blood cells to clump together when added to the cell culture. Finally, the third method is immunofluorescence, which is a technique used to detect the presence of viral antigenetic material in the cell culture.

The two ways to detect the immune reaction triggered by the patient's own immune system are through immunity tests, which determine the presence or absence of antibodies against a specific virus, and diagnostic tests, which detect a high or rising level of antibodies against a specific virus, indicating recent viral illness.