Answer:
cause tumors to develop.
Explanation:
Oncogenic viruses are viruses that do not kill or lyses the cells of the host outright but has the capacity to cause to cause a long term infections that may eventually lead to the formation of tumor or cancerous cells within the body of their hosts.
<em>Hence, the fourth option is the correct option. That is, they cause tumors to develop</em>
Answer:
The correct answer is A) Histone deacetylation generally decreases gene expression.
Explanation:
Histones are the proteins that are responsible for the condensation of chromatin, which is directly linked to the capacity that a gene has to be expressed. The more condensed a gene is, the less expressible it becomes.
In order to regulate the gene expression, histones can suffer from many modifications that can change their conformation and the expressiveness of specific genes.
<u>Histone acetylation is linked with an increase of gene expression; while deacetylation and methylation decrease gene expression.</u>
Answer:
Certain fossils, called index fossils, help geologists match rock layers. To be useful as an index fossil, a fossil must be widely distributed and represent a type of organism that existed for a brief time period.
