Answer:
Bacteriophages (phages) are viruses that infect only bacteria and do not infect mammalian or plant cells. Phages are ubiquitous in the environment. Phages or bacteriophages were chosen as a model system for their simplicity, as they only contained protein-coated nucleic acid. Alfred D. Hershey and Martha Chase (who were part of the bacteriophage group) in 1952 studying the infection of the bacterium Escherichia coli by the T2 phage show that the information definitely resides in the DNA. They used phage with either [32P] -labeled DNA or [35S] -labeled proteins to infect the bacteria. Immediately afterwards, they centrifuged the sample so that the infected bacteria remain in the pellet and the virus capsids (proteins) remain in the supernatant. [35S] is found in the supernatant, whereas [32P] is found in bacteria. After one cycle of infection, it was observed that when phage labeled in the [35S] proteins were used, only 1% of the radioactivity was incorporated into the progeny. But when phages were [32P] labeled, more than 30% of the radioactivity was in the progeny. They showed directly that what is transmitted from one progeny to another is the DNA and not the proteins, despite having first "diluted" in a bacterium.
Explanation:
Bacteriophages are viruses that infect bacteria in a specific way. Bacteriophages, like other known viruses, are found in an intermediate zone between living organisms and inert matter. Bacteriophages bind to the host pathogenic bacterium, introduce their genetic material, replicate inside it and destroy it. Hersey, along with his assistant Martha Chase, used phages because they knew that T2 phages were made up of 50% proteins and 50% nucleic acids and that phages entered bacteria and reproduced. As the progeny carried the same infection traits, the genetic material of this had to be transmitted to the offspring, but the mechanism was unknown. These scientists carried out an experimental work with the T2 virus, a bacteriophage that infects the bacterium Escherichia coli, which it reproduces by attaching itself to the outer wall of the bacterium, injecting its DNA into it where it replicates and directs the synthesis of the phage's own proteins. Phage DNA is encapsulated within proteins and produces phages, which lyse or disrupt the cell and release phage from progeny. They infected a culture of bacteria with radioactively labeled phages: the protein coat with sulfur (35S) and its DNA with phosphorus (32P). After infection, they separated the phages from the bacteria by violent shaking using a mixer (hence the name of the experiment). By centrifugation the much smaller phages remained in the supernatant and the much larger bacteria in the pellet. 85% of the radioactivity corresponding to DNA appeared in the pellet and 82% of the protein in the supernatant. This result supported the idea that DNA was the only component of the bacteriophage that penetrated the interior of the bacteria and, having the ability to form new phages, constituted the genetic material.
His and her child is also AB cause its the blood type of his/her parents
Answer:
mRNA destroyer concentration has a greater influence because it is destroying mRNA before proteins can even be produced.
Explanation:
<em>Proteins are synthesized from mRNA through the process of translation. mRNAs are first synthesized from a coding DNA template through the process of transcription. Hence, if mRNAs are destroyed, it means proteins will not be synthesized at all.</em>
Protein not being synthesized at all means that mRNA destroyer concentration has a greater influence on protein levels than protein degradation. With protein degradation, not all the protein is degraded at once and some quantity of the protein can still be found, but with mRNA destroyer concentration, no protein can be found at all because it was not synthesized in the first place.
I think the answer would be B but none of them are great. Continental drift is the gradual movement of our land masses. Knowing this we can eliminate option D because it identifies buildings as a cause. A and C both discuss climate change which is not a product of continents moving. The elimination leaves option B however because these changes would occur gradually, it is unlikely that species would become invasive.
Answer: choice C)Water molecules are cohesive
Explanation:
The observations point to the <em>cohesive qualities and surface tension of water.</em>
<u>Cohesion refers to the attraction of molecules for other molecules of the same kind, and water molecules have strong cohesive forces thanks to their ability to form hydrogen bonds with one another.</u>
Water is polar and a great solvent but these are not related to the observations stated in the question.
