Florida State University The Role of Capsid Maturation on Adenovirus Response

reply to at least 1 other classmate’s thread whose position, for any 2 of the 7 criteria, is different from your own. The objective is to sway your classmate to your side. If most classmates’ threads are sympathetic to your own, critique their arguments rather than their conclusion. This makes the group’s overall conclusion stronger. In each case your reply must consist of at least 2 concise sentences

this is the post:

1. Living “things” must maintain homeostasis

Are viruses made up of cells? No. Viruses are neither made up of cells nor are they a cell. In their most basic form, they consist purely of hereditary information stored as nucleic acid and a protienacous capsule called the capsid. The capsid contains the nucleic acid and protects it from the environment.

Are viruses able to monitor or create change in their internal environment? No. Virsuses contain no organelles or any other means with which to detect or affect changes within themselves. Viruses do often contain a few enzymes, which assist in uncoating and the delivery of the nucleic acid into the host cell. However, this occurs after the virus is destroyed and does not have an “inside” anymore,

Fail

2. Living “things” have different levels of organization

Do viruses have different levels of organization? No. Viruses aef small enough to fall somewhere between the cellular and molecular levels of organization. Where exactly between those groups they fall is unclear, but it certainly does not fall across both and therefore it does not have different levels of organization.

Fail

3. Living “things” reproduce

Do viruses replicate or reproduce? Yes. After a single virus enters the cell, the cell might soon lyse from all the new virions that formed inside. Although they cannot do it entirely by themselves, viruses can replicate/ reproduce using the host cell machinery.

Pass

4. Living “things” grow

Do viruses grow in size or complexity? No. A given virus will remain the same throughout its “life” cycle. After a cell is infected, the virion does not grow inside their host but instead sacrifices itself to create many copies of identical size and complexity as the original virus.

Fail

5. Living “things” use energy

Do viruses use energy? No. Virus do not have any means of producing or using energy. They rely on passive diffusion to spread from cell to cell. A cell will use energy to endocytose, digest, and begin replicating the viral proteins which spontanesouly assemble. The virus itself never uses energy.

Fail

6. Living “things” respond to stimuli

Do viruses respond to external stimuli? Yes. Some species of viruses can detect interactions on receptors on cell surfaces. When such a virus comes in contact with a specific receptor, it will react by making conformational changes to its capsid to facilitate uncoating.

Maybe

7. Living “things” adapt to their environment

Do viruses adapt to their environment? No. A virus has receptors that only react to specific cell surface markers. In an environment without those markers, a virus is not capable of changing its receptors. On a larger scale, viruses have no evolutionary selection pressures. This means viruses evolve only by random mutations, not by any pressures from the environment.

Fail

References

• Brown, N., & Bhella, D. (2016). Are viruses alive?. Microbiology Today, 43(2), 58-61.
• Schaechter, M., Engleberg, N. C., DiRita, V. J., & Dermody, T. (2013). Schaechter’s mechanisms of microbial disease. Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins.