What is the Baltimore classification of influenza virus?
Baltimore Classification Group I viruses contain double-stranded DNA (dsDNA) as their genome. Their mRNA is produced by transcription in much the same way as with cellular DNA. Group II viruses have single-stranded DNA (ssDNA) as their genome.
Why (+) mRNA is placed at the center of Baltimore classification?
Why + mRNA is placed at the center? Baltimore classification system is based on the central role of translational machinery and placed mRNA in the center, and described the pathways to form mRNA from DNA or RNA genomes. Host cells on the other hand can synthesize proteins only from +mRNA strands.
What are the different classifications of viruses?
Viruses are classified into four groups based on shape: filamentous, isometric (or icosahedral), enveloped, and head and tail. Many viruses attach to their host cells to facilitate penetration of the cell membrane, allowing their replication inside the cell.
What is the most important factor for Baltimore virus classification?
The Baltimore classification of viruses is based on the mechanism of messenger RNA (as discussed earlier). Messenger RNA can also has the ability to replicate itself. Viral genomes may be ssRNA/DNA or dsRNA/DNA. Viruses can or cannot use reverse transcriptase.
What is the significance of the Baltimore classification?
The Baltimore Classification System is a scheme for classifying viruses based on the type of genome and its replication strategy. The system was developed by David Baltimore. Viruses do not contain a complete system for protein translation; therefore, every virus is dependent on host translational machinery.
Why is Baltimore classification important?
The primary advantage of Baltimore classification is that by classifying viruses according to the aforementioned characteristics, viruses that behave in the same manner can be studied as distinct groups. There are seven Baltimore groups numbered with Roman numerals, listed hereafter.
What is the difference between virus and Virion?
Most viruses have either RNA or DNA as their genetic material. The nucleic acid may be single- or double-stranded. The entire infectious virus particle, called a virion, consists of the nucleic acid and an outer shell of protein. The simplest viruses contain only enough RNA or DNA to encode four proteins.
Which of the following viral characteristics are used to classify viruses in the Baltimore classification system?
Baltimore classification (first defined in 1971) is a classification system that places viruses into one of seven groups depending on a combination of their nucleic acid (DNA or RNA), strandedness (single-stranded or double-stranded), Sense, and method of replication.
What Baltimore class is norovirus?
Virology
| Norovirus | |
|---|---|
| Phylum: | Pisuviricota |
| Class: | Pisoniviricetes |
| Order: | Picornavirales |
| Family: | Caliciviridae |
What causes the sudden appearance of new pandemic influenza virus strains?
New influenza strains of influenza virus arise continually as a result of two mechanisms that alter the genetic code in the viral RNA. These mechansims are referred to as genetic drift and genetic shift. Genetic Shifts result from reassortment of genetic material between vastly different strains of influenza viruses.
What is Baltimore system What does it tell us?
How many classes of viruses are there in Baltimore?
The Baltimore Classification System initially included six classes of viruses. However, a seventh class was added to accommodate the gapped DNA genome of Hepadnaviridae (hepatitis B virus). The seven classes of viruses in the Baltimore Classification System are as follows:
How are ssRNA viruses classified in the Baltimore classification?
The ssRNA viruses belong to Class IV or V of the Baltimore classification. They could be grouped into positive sense or negative sense according to the sense of polarity of RNA. The single stranded RNA is the common feature of these viruses. The replication of viruses happens in the cytoplasm or nucleus (for segmented class V viruses).
How is Baltimore classification based on viral genome?
Baltimore classification is chiefly based on the transcription of the viral genome, and viruses within each group typically share the manners by which the mRNA synthesis occurs.
How is the Baltimore classification system based on?
The Baltimore system is based on how viruses use that machinery. Using this classification system, messenger RNA (mRNA) is at the center, and different pathways to mRNA from DNA or RNA genomes denote the different classes. The Baltimore Classification System initially included six classes of viruses.
