28/01/2021
Watch my new video in which I've summarized an article by David Quammen from the National Geographic Magazine.
Link of the full article: https://www.nationalgeographic.com/magazine/2021/02/viruses-can-cause-great-harm-but-we-could-not-live-without-them-feature/
Video link: https://youtu.be/U8ixhAkKX2U
Article Summary by Faizan Asif
""How Viruses Shape Our World"
1. Viruses come and go.
Polio, Ebola, AIDS, Zika virus, they all came and go.
2. We live in a world of viruses.
The oceans alone are abundant with viruses. Mammals and non-mammals, plants, bacteria, and every other possible hosts carry enormous number of viruses.
3. We couldn’t continue without them.
Part of the DNA is originated from viruses and now resides in the genomes of humans and other primates, for instance, without which pregnancy would be impossible. Also, some other genes regulate the immune system, resist cancer - important effects only now beginning to be understood.
4. Whether viruses are good or bad, it depends.
Though the virus is a parasite, but sometimes the parasitism is more like symbiosis, in which both, visitor and host get the profit. Like fire, viruses are a phenomenon that’s neither in all cases good nor in all cases bad; they can deliver advantage or destruction. Everything depends, depends on the virus, on the situation etc.
5. To appreciate.
Our understanding of what the definition of virus is, is continuously evolving for over the past century. It have been defined by its size, that virus is something that’s smaller than bacteria but can cause a disease. But this was just our first steps towards their understanding.
6. The Concept of Virus.
If we dive deeper into the concept of viruses, we would come to know that they’re easier to describe than to define. Each viral particle consists of a stretch of genetic instructions (written either in DNA or RNA) packaged inside a protein capsule.
7. What do they do with the cell.
A virus can copy itself only by entering a cell. After that, either many more viral particles are manufactured, resulting in the destruction of the cell, or it go dormant or back-engineer its little genome into the host’s genome. This means the mixing of genomes, for evolution.
8. Evolutionary Origins of Viruses
There are many hypotheses about the evolutionary origins of viruses. All of which explains that how the viruses played different strategies over time for their survival.
9. Mimivirus - The Giant virus
A giant virus was found named Mimivirus, because it mimicked bacteria, at least with regard to size. A similar type of virus was also found, named Pandoravirus.
10. Discovery of the giant viruses.
These discoveries about giant viruses inspired other scientists to formulate what viruses are, and what constructive roles they have played in the evolution of cellular life.
Virus had inadequate definitions for itself, but that did change with the virocell concept. That takes the concept of virus to another level.
11. Genetic-Diversity
Another view is that viruses are the preeminent font of genetic diversity.
12. In the olden days. (syncytin-2 - The virus important for human pregnancy)
Syncytin-1 and syncytin-2 are viral genes which are part of human genome and they are important for human pregnancy.
13. Retrovirus
Backward operating viruses, which make DNA from RNA instead of the vice versa, are called retroviruses. Some retroviruses infect reproductive cells and, in the consequence, 8 percent of the human genome consists of this viral DNA.
These viruses now raise new questions about evolution. Theirry Heidmann said, “Our genes are not only our genes, our genes are also retro-viral genes.”
14. The contribution.
Other contributions of these retroviruses are storing information within neural networks, protecting embryo from viral infections and fetal development.
And if 8 percent of our genome is retro-viral DNA, then it means that these viruses are a part of our being.
15. The downside.
The downside is that sometimes a spillover can happen, resulting in human infectious diseases.
16. Conclusion
So viruses give and viruses take away. And they’ve made things much more complicated now. We don’t know that how much should we rely on the evolution theory by Charles Darwin, as Darwin didn’t know about genes and viruses. And if reflecting upon our own viral contents takes away some of our human pride, then I leave it you to say whether those are benefits or harms.
This is an article summary and review from the National Geographic Magazine. Article is by David Quammen, summary provided by Faizan Asif.Full article link: ...
