10.2: Size and Shapes of Viruses - Biology LibreTexts
Aug 31, 2023 · Viruses are usually much smaller than bacteria with the vast majority being submicroscopic, generally ranging in size from 5 to 300 nanometers (nm). Helical viruses consist of nucleic acid surrounded by a hollow protein cylinder or capsid and possessing a …
THE BIOLOGY OF INFLUENZA VIRUSES - PMC - PubMed Central …
The influenza viruses are characterized by segmented, negative-strand RNA genomes requiring an RNA-dependent RNA polymerase of viral origin for replication. The particular structure of the influenza virus genome and function of its viral proteins enable antigenic drift and antigenic shift. These processes result in viruses able to evade the ...
Types of Influenza Viruses | Influenza (Flu) | CDC
Sep 18, 2024 · There are four types of influenza viruses: A, B, C, and D. Influenza A and B viruses cause seasonal epidemics of disease in people (known as flu season) almost every winter in the United States. Influenza A viruses are the only influenza viruses known to cause flu pandemics (i.e., global epidemics of flu disease).
Influenza Virus (Flu) - Baylor College of Medicine
Influenza virus has a rounded shape (although it can be elongated or irregularly shaped) and has a layer of spikes on the outside. There are two different kinds of spikes, each made of a different protein – one is the hemagglutinin (HA) protein and the other is the neuraminidase (NA) protein.
Virology of human influenza - World Health Organization (WHO)
May 13, 2010 · Influenza viruses have a single-stranded, negative-sense RNA genome and a pleiomorphic (non-uniform) envelope with a diameter of 50–120 nm. HA and NA glycoproteins form “spikes” that are spread over the surface of the viral particle.
Molecular Expressions Cell Biology: The Influenza (Flu) Virus
Nov 13, 2015 · The structure of the influenza virus (see Figure 1) is somewhat variable, but the virion particles are usually spherical or ovoid in shape and 80 to 120 nanometers in diameter. Sometimes filamentous forms of the virus occur as well, and are more common among some influenza strains than others.
An Overview of Influenza Viruses and Vaccines - PMC
There are four genera of influenza virus that infect vertebrates: influenza virus A, B, C, and D which are distinguished based on antigen differences in their matrix protein and nucleoprotein. Type A is by far the most virulent virus that causes severe respiratory disease or death.
The structure of the influenza A virus genome | Nature …
Jul 22, 2019 · Influenza A viruses (IAVs) constitute a major threat to human health. The IAV genome consists of eight single-stranded viral RNA segments contained in separate viral ribonucleoprotein (vRNP)...
Structure and Function of the Influenza Virus Transcription and ...
Influenza virus RNAs and viral ribonucleoprotein (vRNP) structure. (A) Influenza virus viral RNAs (vRNAs). The influenza A virus genome consists of eight segments of single-stranded negative sense vRNA.
Molecular Anatomy of Influenza Virus Detailed
A team of researchers led by NIAMS' Alasdair Steven, Ph.D., working with a version of the seasonal H3N2 strain of influenza A virus, has been able to distinguish five different kinds of influenza virus particles in the same isolate (sample) and map the …