We are all aware of the pandemic caused by the coronavirus. It is not easy to kill viruses. Have you ever thought about why it is very difficult to destroy viruses? Viruses keep on changing their genetic material. That's why it is very difficult to make vaccines to kill viruses. To know more about plant and animal viruses and the difference between them, continue reading.
Plant viruses are the viruses that infect plants and these are obligatory viruses that mean they can't replicate or reproduce without the host. As viruses do not have cellular machinery they use the machinery of plant cells to replicate and reproduce.
Viruses are made up of two components: proteins and genetic material. Protein subunits are placed around the circumference of the circle to form a disc. Then these discs are stacked around the genetic material of the virus and form a complete virus.
There are various shapes of plant viruses but most of the viruses are rod-shaped. And the length of these viruses is between 300-500nm. Isometric is the second most common shape of the plant virus. These types of viruses may have a double protein coat that is associated to form an icosahedral-shaped part. Very few plant viruses may have a lipid coat. The genetic material of plant viruses may be double or single-stranded DNA. But in most cases, single-stranded RNA is the genetic material of plant viruses.
An example of plant viruses that have double-stranded DNA as genetic material is the cauliflower mosaic virus. Bean golden mosaic virus is a plant virus that has single-strand DNA as genetic material. The tobacco mosaic virus is a plant virus that has single-stranded RNA as the material.
The animal virus is a virus that infects animals and other viruses. This virus is also unable to replicate outside the animal body or animal cell. Animal viruses are also made of two components: protein and genetic material. The protein coat is known as capsid and genetic material is present inside it. Animal viruses also have an envelope made of lipids.
There are various shapes of animal viruses, such as helical and icosahedral. The shape of the Ebola virus is long like a thread. The genetic material of animal viruses is made of double-stranded DNA or RNA, single-stranded DNA or RNA. They used to cause various types of diseases in animals and humans. Herpesvirus and poxvirus are viruses made of double-stranded DNA.
The genetic material of hepatitis B, herpes, and pox virus is double-stranded DNA. The genetic material of parvovirus is single-stranded DNA. Picornavirus is a single-stranded RNA virus. R reovirus is a double-stranded RNA virus.
Q1. What are animal virus infections called?
Ans: Infections that occur through animal viruses are called zoonotic or viral zoonoses. Examples are rabies and yellow fever.
Q2. What are the main characteristics of plant viruses?
Ans: The most common shape of a plant virus is a rod shape with a protein disc forming a tube around the viral genome.
Q3. Are viruses living or nonliving?
Ans: Viruses are not made of cells so they can't be considered living but they are not also dead because they replicate inside the host cell.
In conclusion, we learnt that viruses are infectious microbes that are made of protein and genetic material. Plant and animal viruses cause infection in plants and animals, respectively. We have also studied a table listing the differences between plants and animal viruses. We hope to have helped you with your queries. You can go through the important and practise questions to test your knowledge as well the following links for further readings.
1. Write a few characteristics of viruses.
The main characteristics of viruses are as given below:
The viruses did not get any place in the five kingdom classification of Whittaker because they are not truly living.
Viruses are smaller and simple types of microorganisms
They are very small that they get filtered from filter paper
They are obligate parasites which means they can't replicate without the host.
They multiply in the host organism using their machinery
Viruses consist of only two components proteins and genetic material
Viruses cause various diseases in plants and animals such as aids, hepatitis, polio, etc.
2. What are the different classes of animal viruses?
There are different classes of animal viruses based on genetic material. These are as follows:
DNA viruses have a group I and group II
RNA viruses have group III and group lV and group V
RT viruses have groups VI and VII
Group I and group II are under DNA viruses, They have deoxyribonucleic acid as genetic material.
Group III, group IV, and group V under RNA viruses have ribonucleic acid as genetic material.
Group Vl and group Vll are under reverse transcribing viruses and genetic material made of either DNA or RNA and replicate with the help of the reverse transcription process.
3. What is the difference between viruses and viroids?
The table below list the difference between viruses and viroids:
Viruses | Viroids |
The virus is an infectious agent that causes diseases in plants and animals | Viroids are smaller than viruses and known to cause various diseases |
Viruses are made up of nucleic acid, and protein. | Viroids are made of only nucleic acid |
Nucleic acid is either DNA or RNA | The nucleic acid of viroids is only RNA |
The replication process occurs in viruses to produce protein | Do not create protein during the replication process |
Viruses infect both plants and animal cells | Viroids only infect the plant cells |
Diseases caused by viruses are influenza. | Disease caused by viroids are potato spindle tuber viroid |