What is the structure of animal viruses?
Like other viruses, animal viruses are tiny packages of protein and nucleic acid. They have a protein shell, or capsid, and genetic material made of DNA or RNA that’s tucked inside the caspid. They may also feature an envelope, a sphere of membrane made of lipid. Animal virus capsids come in many shapes.
How do you determine the structure of a virus?
Viruses are much smaller than bacteria and consist of a single- or double-stranded nucleic acid (DNA or RNA) surrounded by a protein shell called a capsid; some viruses also have an outer envelope composed of lipids and proteins. They vary in shape. The two main classes are RNA viruses and DNA viruses.
What are the 4 structures of viruses?
Viruses are classified into four groups based on shape: filamentous, isometric (or icosahedral), enveloped, and head and tail.
What are 4 identifying characteristics of viruses?
These are: 1) attachment; 2) penetration; 3) uncoating; 4) replication; 5) assembly; 6)release. As shown in , the virus must first attach itself to the host cell. This is usually accomplished through special glycoprotiens on the exterior of the capsid, envelope or tail.
What are some shapes of animal viruses?
Morphology. In electron micrographs of low resolution, virions appear to possess two basic shapes: spherical and cylindrical.
Which part of an animal virus structure is responsible for host recognition?
The proteins in the envelope can include glycoproteins, which act as receptor molecules. These receptor molecules allow host cells to recognize and bind the virions, which may result in easier uptake of the virion into the cell.
What are the three types of viral structures?
Structure of Viruses
- Helical Viruses. Helical capsids are made up of a single type of protein subunit stacked around a central axis to form a helical structure.
- Icosahedral Viruses.
- Complex Viruses.
What is the structure and function of a virus?
A complete virus particle is called a virion. The main function of the virion is to deliver its DNA or RNA genome into the host cell so that the genome can be expressed (transcribed and translated) by the host cell. The viral genome, often with associated basic proteins, is packaged inside a symmetric protein capsid.
What are the 3 viral shapes?
Viruses may also be classified according to the structure of the virus particle, or virion. The three major shapes seen are spherical, filamentous, and complex.
How are animal viruses identified and characterized in aquatic animals?
Aquatic animal viruses are isolated and identified according to standard virological procedures (Essbauer and Ahne, 2001 ), but culture-dependent characterization is not always possible.
What are animal viruses divided into?
Animal viruses can be divided into DNA and RNA viruses, depending on the nature of their genomes. DNA and RNA viruses are described in Part II and Part III, respectively. In Part IV, two virus families, which replicate their genome via reverse transcription (RT), will be described ( Fig. PIV.1 ).
How are viruses classified based on their morphology?
Classification of Viruses Morphology:Viruses are grouped on the basis of size and shape, chemical composition and structure of the genome, and mode of replication. Helical morphology is seen in nucleocapsids of many filamentous and pleomorphic viruses.
What is the structure and function of virus?
Structure and Function. Viruses are small obligate intracellular parasites, which by definition contain either a RNA or DNA genome surrounded by a protective, virus-coded protein coat. Viruses may be viewed as mobile genetic elements, most probably of cellular origin and characterized by a long co-evolution of virus and host.