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Viruses that carry RNA as their genetic material accumulate mutations more rapidly than DNA-based viruses because

According to this phylogentic tree, which modern organism evolved longest ago? A timeline runs horizontally across the top, marked in millions of years ago from 55 on the left to 25 on the right. The tree consists of branching lines connecting various organisms, with each horizontal line segment colored to correspond with the timeline above it. The first branch at the top shows a modern hippopotamus labeled A, with its branch extending from approximately 55 million years ago to the present. Below this, a brown mammal with a long tail branches off at approximately 50 million years ago and exists for about 5 million years. The next branch shows organism B, a four-legged creature with a spotted pattern labeled with a magenta letter, branching off at approximately 48 million years ago and existing for about 3 million years. Below this, a pale-colored four-legged animal appears in a running or walking pose, branching at approximately 46 million years ago and existing for about 4 million years. Organism C, labeled with a magenta letter, appears as a sleek four-legged creature with an elongated body and tail, branching at approximately 43 million years ago and existing for about 3 million years. Below this is a gray aquatic mammal with four flipper-like limbs, branching at approximately 41 million years ago and existing for about 6 million years. The tree then shows two more ancient whale-like creatures with elongated bodies and reduced limbs, the first existing from approximately 38 to 33 million years ago. Near the bottom, the tree splits into two long branches that extend to the right edge of the timeline. One branch shows a blue whale or dolphin with a dorsal fin, existing from approximately 35 million years ago to the present. The other branch shows organism D, labeled with a magenta letter, which is a large purple whale with a massive body and tail flukes, also existing from approximately 35 million years ago to the present.

Tracing the evolutionary history of a species or group of species is called ______.

Why might a scientist use the gel electrophoresis process after conducting PCR?

Why must the transcription and translation machinery be so much more organized in eukaryotes than in prokaryotes?

In which of the following examples would a DNA point mutation be most likely to NOT have a deleterious effect on the final protein?

T2 phage viruses are very simple; they are composed of DNA or RNA enclosed by a protein coat. When the phages are grown it is possible to radioactively label the DNA component only. For the second part of their experiment, Hershey and Chase allowed bacteria to be infected by the radioactively labeled T2 phage virus.  After allowing them to grow and reproduce, the bacterial cells were processed by centrifugation and the resulting pellet and supernatant were tested for radioactivity. If protein were the hereditary material instead of DNA, where would you expect to find radioactivity?

A template strand of DNA is: 5′ CGT AGC 3′ What is corresponding strand of mRNA?

______ is based on mutation; mutation is the primary source of all genetic variation.

T2 phage viruses are very simple; they are composed of DNA or RNA enclosed by a protein coat. When the phages are grown it is possible to radioactively label the DNA component only. For the second part of their experiment, Hershey and Chase allowed bacteria to be infected by the radioactively labeled T2 phage virus.  After allowing them to grow and reproduce, the bacterial cells were processed by centrifugation and the resulting pellet and supernatant were tested for radioactivity. What result do you expect?