The incorrect among the choices is "<span>direct signaling involves the activation of g proteins"
This is incorrect because direct signaling does not involve the activation of g proteins rather it involves the activation of ion channels resulting to either an excitation reaction (depolarization of the membrane) or an inhibition reaction (hyperpolarization of the membrane); and this will ultimately affect the action of the organ the nerve is innervating.</span>
Answer:
Distinct mechanisms are used by bacteria in order to transfer the gene from one bacteria to another. These are transformation, transduction, and conjugation. Transformation refers to the process of uptaking extracellular DNA by the recipient of the other bacterial cell.
In the process of transduction, the donor DNA gets packed within the bacteriophage and infects the recipient bacteria. In the process of conjugation, the genetic substance is transferred by the donor bacteria to the recipient via the process of mating.
a. Of all these three mechanisms, transformation is the process that exhibits a broad range and can be easily performed in the lab. As in the process, there is a slight chance of rejection or failure due to direct compatibility between the bacteria.
b. While the narrowest broad range is found in the process of conjugation, as in order to transfer the genetic substance between the two bacterial species, there should be a similarity between the two species so that they can mate and exchange the genetic substance in between them.
I do not believe it is possible for long periods of time. If the intestines are still intact, one can live for up to a certain period of time without medical help. However, this is an extremely short period of time.
EDTA inhibits the activity of DNase during DNA isolation process.
DNase is an enzyme which degrades DNA using divalent metal ions like Mg^{2+} . These metal ions act as cofactor for the proper functioning of DNase.
EDTA chelates the divalent metal ions and thus does not allow DNase to access them.
Therefore in this way DNA is prevented from degradation during its isolation.