Hi,
Harshey and Chase did a great experimentation which was basically a two step experiment to prove that DNA and not proteins are the actual carriers of genetic information from parents to offspring.
- In the first part of their experiment, they used bacteriophages (virus that eat bacteria). They used radioactively labeled sulphur(35S) medium to grow bacteriophages and observed that all the bacteriophages had proteins with radioactive sulphur(35S).
- In the next step they allowed these phages to infect bacteria and to their surprise, they found that the bacteria did not had radioactively labeled sulphur in them because the coat of bacteriophage stays outside the body of bacteria when it attacks it. This proved that DNA not proteins were the hereditary material.
- To make their results more reliable, they did a second experimentation in which, they marked the DNA of the phage with radioactive phosphorus 32P. After labeling DNA, they repeated the same experiment and this time, they found radioactive phosphorus inside the bacteria.
<em>This meant that the bacteria had DNA of phage entered inside them and this again proved that DNA not proteins are the hereditary material. You can see attached image for better understanding.
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Hope it help!
What we know about shark and ray fossils comes from bones in rocks from the Cretaceous period in Mexico that left behind, their only hard parts.
<h3>Shark fossils</h3>
The idea of a stingray-like shark may seem like something out of a B-movie. But paleontologists have just reported the discovery of such a creature in Cretaceous rocks in Mexico. This strange shark combines a streamlined body with large, wing-shaped fins, an ancient animal unlike any seen in the fossil record.
<h3>Whose are the fossils?</h3>
Fossils are the remains or traces of living beings that inhabited the Earth in previous geological periods. Fossil remains are parts of animals or plants, such as a bone or some limb or organic remains that have been preserved in some way.
With this information, we can conclude that Fossils are remains or traces of animals and plants preserved in rocks.
Learn more about Fossils in brainly.com/question/22502144
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I believe C) preserving biodiversity is the answer