Table of Contents
- 1 What are the steps of a virus?
- 2 What are the five steps used by viruses to get into the cell?
- 3 How are viruses caused?
- 4 What is the first step of the virus reproduction cycle?
- 5 Which step in the replication cycle of viruses do you think is most critical for the virus to infect cells explain why?
- 6 How does a virus get into the host cell?
- 7 Which is an example of a virus that kills the host?
What are the steps of a virus?
Key Points
- Viral replication involves six steps: attachment, penetration, uncoating, replication, assembly, and release.
- During attachment and penetration, the virus attaches itself to a host cell and injects its genetic material into it.
What are the five steps used by viruses to get into the cell?
Most productive viral infections follow similar steps in the virus replication cycle: attachment, penetration, uncoating, replication, assembly, and release (Figure 1).
How are viruses caused?
Viruses can be transmitted in a variety of ways. Some viruses can spread through touch, saliva, or even the air. Other viruses can be transmitted through sexual contact or by sharing contaminated needles. Insects including ticks and mosquitoes can act as “vectors,” transmitting a virus from one host to another.
What are the steps of virus replication?
Viral replication involves six steps: attachment, penetration, uncoating, replication, assembly, and release.
How a virus gets into a cell?
For an enveloped virus, the virus enters the cell by attaching to an attachment factor located on the surface of the host cell. It then enters by endocytosis or a direct membrane fusion event. The fusion event is when the virus membrane and the host cell membrane fuse together allowing a virus to enter.
What is the first step of the virus reproduction cycle?
The first stage is entry. Entry involves attachment, in which a virus particle encounters the host cell and attaches to the cell surface, penetration, in which a virus particle reaches the cytoplasm, and uncoating, in which the virus sheds its capsid.
Which step in the replication cycle of viruses do you think is most critical for the virus to infect cells explain why?
The assembly step is the most critical because new virions are assembled to infect cells. The entry step is the most critical as nucleic acid of virus needs to enter the host cell naked, leaving the capsid outside.
How does a virus get into the host cell?
From there, the viral DNA gets incorporated into the host’s DNA and the host’s cells. Each time the host’s cells go through replication, the virus’s DNA gets replicated as well, spreading its genetic information throughout the host without having to lyse the infected cells. In humans, viruses can cause many diseases.
What are the steps in the replication of a virus?
Although the replicative life cycle of viruses differs greatly between species and category of virus, there are six basic stages that are essential for viral replication. 1. Attachment: Viral proteins on the capsid or phospholipid envelope interact with specific receptors on the host cellular surface.
What happens to a virus when it is reactivated?
If the viral genome is reactivated, a productive infection results, leading to viral replication and disease signs again. The flow of information for ssDNA viruses, such as the parvoviruses, will still follow the conventional pathway, to a certain extent: DNA → mRNA → protein.
Which is an example of a virus that kills the host?
For example, the flu is caused by the influenza virus. Typically, viruses cause an immune response in the host, and this kills the virus. However, some viruses are not successfully treated by the immune system, such as human immunodeficiency virus, or HIV.