True, causal contact is safe and does not spread HIV
Answer:
See the answer below
Explanation:
A DNase is also known as deoxyribonuclease and it is an enzyme that catalyzes the degradation of deoxyribonucleic acid by cleaving the phosphodiester linkage in their structures. Thus,<em> if the RNA is treated with a DNase before the plants are exposed to it, it will not make any difference. The plants will develop the same types of lesions as if they have been exposed to the mosaic virus.</em>
Unlike DNase, RNase is a ribonuclease, an enzyme that is capable of carrying out catalytic degradation of ribonucleic acids. <em>This means that if the RNA is treated with RNase before the plants are made to be exposed to it, they will not develop the lesions because the RNA would have been degraded by the enzyme.</em>
A protease is an enzyme that degrades the structure of proteins. <em>Treating a RNA with protease will thus have no effect on the structure of the RNA. Exposing the plants to the protease-treated RNA will make no difference. The plants will still come down with the lesions as if they have been exposed to the virus. </em>
The answers are insertion, deletion and substitution respectively.
<h3><u>Explanation</u>:</h3>
The mutation is the phenomenon which includes some alteration of the genetic material of the organism by either insertion, deletion or substitution of one or more nitrogen base pairs by others. This phenomenon was invented by Scientist Sir Hugo de Vries, who was also called as the Father of Mutation.
The insertion includes the addition of one or few nitrogen base pairs within the DNA which changes the codon pattern, thereby changing the protein coded from that part of DNA. T
The deletion includes the deletion of a part of DNA with similar effect as that of Insertion.
The substitution is the change of nitrogen bases by other bases which also leads to change in protein produced by the part of Genetic material.
Answer:
The volcanic activity led to the release of large amounts of carbon dioxide at the end of the Devonian period
Explanation:
Devonian period is refereed as the Age of fish. It is also called an era of mass Extinction. During the end of Devonian period most of the terrestrial animals were extinct from Earth. Another big feature of Devonian period was massive volcanic activity which contributed to the release of carbon dioxide in the environment.
