Cytopathic effectCytopathic effect or cytopathogenic effect (abbreviated CPE) refers to structural changes in host cells that are caused by viral invasion. The infecting virus causes lysis of the host cell or when the cell dies without lysis due to an inability to replicate. Both of these effects occur due to CPEs. If a virus causes these morphological changes in the host cell, it is said to be cytopathogenic. Common examples of CPE include rounding of the infected cell, fusion with adjacent cells to form syncytia, and the appearance of nuclear or cytoplasmic inclusion bodies.
RhinovirusThe rhinovirus (from the rhis "nose", ῥινός, romanized: "of the nose", and the vīrus) is the most common viral infectious agent in humans and is the predominant cause of the common cold. Rhinovirus infection proliferates in temperatures of 33–35 °C (91–95 °F), the temperatures found in the nose. Rhinoviruses belong to the genus Enterovirus in the family Picornaviridae. The three species of rhinovirus (A, B, and C) include around 165 recognized types that differ according to their surface antigens or genetics.
VirologyVirology is the scientific study of biological viruses. It is a subfield of microbiology that focuses on their detection, structure, classification and evolution, their methods of infection and exploitation of host cells for reproduction, their interaction with host organism physiology and immunity, the diseases they cause, the techniques to isolate and culture them, and their use in research and therapy.
InbreedingInbreeding is the production of offspring from the mating or breeding of individuals or organisms that are closely related genetically. By analogy, the term is used in human reproduction, but more commonly refers to the genetic disorders and other consequences that may arise from expression of deleterious recessive traits resulting from incestuous sexual relationships and consanguinity. Animals avoid incest only rarely. Inbreeding results in homozygosity, which can increase the chances of offspring being affected by recessive traits.
CoinfectionCoinfection is the simultaneous infection of a host by multiple pathogen species. In virology, coinfection includes simultaneous infection of a single cell by two or more virus particles. An example is the coinfection of liver cells with hepatitis B virus and hepatitis D virus, which can arise incrementally by initial infection followed by superinfection. Global prevalence or incidence of coinfection among humans is unknown, but it is thought to be commonplace, sometimes more common than single infection.
Viral life cycleViruses are only able to replicate themselves by commandeering the reproductive apparatus of cells and making them reproduce the virus's genetic structure and particles instead. How viruses do this depends mainly on the type of nucleic acid DNA or RNA they contain, which is either one or the other but never both. Viruses cannot function or reproduce outside a cell, and are totally dependent on a host cell to survive. Most viruses are species specific, and related viruses typically only infect a narrow range of plants, animals, bacteria, or fungi.
History of virologyThe history of virology – the scientific study of viruses and the infections they cause – began in the closing years of the 19th century. Although Louis Pasteur and Edward Jenner developed the first vaccines to protect against viral infections, they did not know that viruses existed. The first evidence of the existence of viruses came from experiments with filters that had pores small enough to retain bacteria. In 1892, Dmitri Ivanovsky used one of these filters to show that sap from a diseased tobacco plant remained infectious to healthy tobacco plants despite having been filtered.
RabiesRabies is a viral disease that causes encephalitis in humans and other mammals. It was historically referred to as hydrophobia ("fear of water") due to the symptom of panic when presented with liquids to drink. Early symptoms can include fever and tingling at the site of exposure. These symptoms are followed by one or more of the following symptoms: nausea, vomiting, violent movements, uncontrolled excitement, fear of water, an inability to move parts of the body, confusion, and loss of consciousness.
Peppered mothThe peppered moth (Biston betularia) is a temperate species of night-flying moth. It is mostly found in the northern hemisphere in places like Asia, Europe and North America. Peppered moth evolution is an example of population genetics and natural selection. The caterpillars of the peppered moth not only mimic the form but also the colour of a twig. Recent research indicates that the caterpillars can sense the twig's colour with their skin and match their body colour to the background to protect themselves from predators.
Ethyl methanesulfonateEthyl methanesulfonate (EMS) is a mutagenic, teratogenic, and carcinogenic organic compound with formula C3H8SO3. It produces random mutations in genetic material by nucleotide substitution; particularly through G:C to A:T transitions induced by guanine alkylation. EMS typically produces only point mutations. Due to its potency and well understood mutational spectrum, EMS is the most commonly used chemical mutagen in experimental genetics. Mutations induced by EMS exposure can then be studied in genetic screens or other assays.