The difference between these three types of zebras is only about where do zebras live and the answer is that they live at different places. One type of zebra wants to live on mountains and is known as a mountain zebras. Second type lives on plain, grassy lands and is called as Burchell's zebras. Third type of these animals is better known as Grevy's zebras. These zebras are the largest of all three types of the species.
An oncovirus is a virus that can cause cancer. This term originated from studies of acutely transforming retroviruses in the 1950â60s, often called oncornaviruses to denote their RNA virus origin. It now refers to any virus with a DNA or RNA genome causing cancer and is synonymous with tumor virus or cancer virus..The vast majority of human and animal viruses do not cause cancer, probably because of longstanding co-evolution between the virus and its host.t now refers to any virus with a DNA or RNA genome causing cancer and is synonymous with tumor virus or cancer virus.. The vast majority of human and animal viruses do not cause cancer, probably because of longstanding co-evolution between the virus and its host.
Today, it is estimated that viruses are responsible for almost 20 percent of cancer cases worldwide. Seven viruses have been connected to specific types of malignancies; itâs now known, for example, that the human papillomavirus (HPV) causes cervical cancer and some types of head and neck cancer.While viruses can cause cancer in a variety of ways, the actual mechanisms fall into two broad categories.In the direct method, oncoviruses (cancer-causing viruses) infect normal cells and slip some of their genes into the cellsâ DNA, causing the cells to produce a few abnormal proteins.n 1958, when scientists linked an aggressive form of leukemia to infection with a particular virus, some researchers took the discovery as evidence that nearly all cancers are caused by viruses.