Search results
Results from the WOW.Com Content Network
Subviral agents are pathogenic entities that can cause disease, but lack various fundamental properties of viruses. Subviral agents consist of satellites , viroids , prions , defective interfering particles , viriforms , and, most recently, obelisks .
Viroids were shown to consist of short stretches (a few hundred nucleotides) of single-stranded RNA and, unlike viruses, did not have a protein coat. Viroids are extremely small, from 246 to 467 nucleotides, smaller than other infectious plant pathogens; they thus consist of fewer than 10,000 atoms.
Virusoids and viroids have been compared to circular introns due to their size similarity. It has been proposed that virusoids and viroids originated from introns. [19] [20] Comparisons have been made between the (-) strand of viroids and the U1 small nuclear ribonucleoprotein particle , implicating that viroids could be escaped introns.
A prion / ˈ p r iː ɒ n / ⓘ is a misfolded protein that induces misfolding in normal variants of the same protein, leading to cellular death.Prions are responsible for prion diseases, known as transmissible spongiform encephalopathy (TSEs), which are fatal and transmissible neurodegenerative diseases affecting both humans and animals.
"Germ" refers not just to bacteria but to any type of microorganism, such as protists or fungi, or other pathogens, including parasites, viruses, prions, or viroids. [1] Diseases caused by pathogens are called infectious diseases. Even when a pathogen is the principal cause of a disease, environmental and hereditary factors often influence the ...
Viroids were known to exist in plants and cause pathology, and there had been no evidence that they were in animals or bacteria. [5] This marks the first time a viroid or viroid-like object has been found in bacteria or animals.
Gamma phage, an example of virus particles (visualised by electron microscopy) Virology 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 ...
Humans can be infected with many types of pathogens, including prions, viruses, bacteria, and fungi, causing symptoms like sneezing, coughing, fever, vomiting, and potentially lethal organ failure. While some symptoms are caused by the pathogenic infection, others are caused by the immune system's efforts to kill the pathogen, such as ...