The flow diagram identifies relationships between bacterial strains in various F factor states. For each of the four arrows in the diagram, provide a description of the events involved in the transition.

Question

The flow diagram identifies relationships between bacterial strains in various F factor states. For each of the four arrows in the diagram, provide a description of the events involved in the transition.

Diagram showing transitions between bacterial strains: F⁻ to F⁺ by conjugation, F⁺ to Hfr by integration, Hfr to F′ by excision, and F′ to F⁻ by loss.

Accepted Answer

Hi, everybody. Here's our next problem. It says identify the letter in the flow chart showing a transition where an error occurs during integration, resulting in F factor being excised along with eight adjacent chromosomes. Choice A is number one, F minus two F plus. Um This transition is shown with an arrow. So F minus arrow F plus towards B number two F plus arrow to H F R to AC three H F R arrow two F plus N choice D number 4h F R arrow to F prime. So let's think this through these and think about what's happening in each of these transitions knowing that we're looking for one where there's an error occurred during integration that results in the F factor being excised along with adjacent chromosomes. So choice A that shows F minus to F plus is a simple acquiring of a plasmid through conjugation. Your donor cell has the F factor. Your recipient cell doesn't, the plasmid travels through the pylos during conjugation and the recipient cell now is F plus as it's acquired a copy of the plasmid. So that's not what we're looking for. So we can cross that out. Choice B is F plus two H F R and that occurs when the plasmid with its F factor is incorporated into the recipient chromosome. So instead of just the plasmid transferring and being a plasmid in the new cell, the whole plasmid chromosome incorporates right into the chromosome of the recipient cell, but that's not what we're looking for. So choice C is not our answer. Then choice C H F R two F plus and this would occur and this occurs when the H F R chromosome transfers two and F minus cell along with its, its, its F factor. So the recipient cell was an F minus cell. Now it's gotten the F factor from the H F R cell, but this isn't what we're looking for. So finally, we're on to choice D H F R two F prime. And this is our correct answer H F R to F prime is when the H F R cell transfers most of its chromosome to the recipient cell. But the F factor doesn't transfer completely. So you don't have an F plus cell as a result because your recipient cell has not inherited an intact F factor. And that makes it what's called an F prime cell. So again, which is a, a transition where an error has occurred during integration, resulting in F factor being excised along with adjacent chromosomes. Choice DH F R two F prime. See you in the next video

The flow diagram identifies relationships between bacterial strains in various F factor states. For each of the four arrows in the diagram, provide a description of the events involved in the transition.

Verified video answer for a similar problem:

Key Concepts

F Factor and Its States

Bacterial Conjugation Mechanism

Integration and Excision of the F Factor