Yacoubb's Bio 3+4 Questions

[wallah]

fe, thank-You

[wallah]

Hey guys, I just have 2 more questions, any help would be really great 


Q1:our class had a SAC today in which we performed electrophoresis on DNA fragments from certain similar species of glofishes but from different countries, and then there was a question, "by seeing the results of electrophoresis, what can you state about the origins of the glofishes?" and I was not sure what to write for that?

Results:

                        (-)                  (+)

Standard Fish   :: ]    ]     ]      ]
Control Fish      :: ]    ]            ]
---------- Fish 1  :: ]    ]     ]      ]
---------- Fish 2  :: ]    ]     ]      ]
---------- Fish 3  :: ]    ]     ]      ]
---------- Fish 4  :: ]    ]     ]      ]

WHERE ] REPRESENTS A BAND

....

So my question is, what would be an appropriate answer for the origins of the fishes?

Q2: "How would you isolate a COPY of a gene? List 2 ways."
I wrote PCR or Gene Cloning, as I focused more on the word COPY, but now I'm confused because I remembered the word ISOLATE....




Thanks

[Yacoubb]

Hey guys, I just have 2 more questions, any help would be really great 


Q1:our class had a SAC today in which we performed electrophoresis on DNA fragments from certain similar species of glofishes but from different countries, and then there was a question, "by seeing the results of electrophoresis, what can you state about the origins of the glofishes?" and I was not sure what to write for that?

Results:

                        (-)                  (+)

Standard Fish   :: ]    ]     ]      ]
Control Fish      :: ]    ]            ]
---------- Fish 1  :: ]    ]     ]      ]
---------- Fish 2  :: ]    ]     ]      ]
---------- Fish 3  :: ]    ]     ]      ]
---------- Fish 4  :: ]    ]     ]      ]

WHERE ] REPRESENTS A BAND

....

So my question is, what would be an appropriate answer for the origins of the fishes?

Q2: "How would you isolate a COPY of a gene? List 2 ways."
I wrote PCR or Gene Cloning, as I focused more on the word COPY, but now I'm confused because I remembered the word ISOLATE....




Thanks

Based on the bands being extremely similar, this suggests that they are genetically identical and so have originated from the same fertilised egg. Their genome would be the same, and thus, separating DNA fragments by electrophoresis would yield the same results.

^ Someone should clarify if my reasoning is right though

[wallah]

Yeah (thanks for replying though ) based on the similarity, I also stated that they must have originated from the same ancestors, how-ever if someone could clarify this, it would be great ....

Also, please do answer the second question

[Yacoubb]

Yeah (thanks for replying though ) based on the similarity, I also stated that they must have originated from the same ancestors, how-ever if someone could clarify this, it would be great ....

Also, please do answer the second question

What DNA fragments were used? I wouldn't say ancestral because there would be some genetic variability over time. Again, I could be wrong.

PCR and Gene cloning sound like good ways to isolate multiple copies of a gene. Of course, a restriction endonuclease would cut & isolate a particular gene, and then multiple copies of the gene, that is isolated, would then be made.

[vox nihili]

I wouldn't say ancestral because there would be some genetic variability over time. Again, I could be wrong.

It really depends on the trait. I haven't really got the time to have a proper look into the question you're doing, but just as a relevant aside.
Whether or not there is a lot of variability in particular genes really depends on the gene that you're looking at. If the gene codes for a limb (let's pretend there's only one for a second) then you could expect variability, as minor changes are unlikely to impact the survival of the organism that much. As we know, over time minor changes become big changes. If the gene coded for, for example, something to do with the metabolism of the cell, you can expect a much smaller amount of variation even between species with a fairly distant ancestor. This is because minor changes really do make a massive difference. So it really depends on what the gene does and whether selection will wipe out the mutations quickly or not.

Think about it like a car. Replace a seat cover, no biggie. Replace the gear box, we may have a problem.

[Yacoubb]

At different times of the year, members of a population of water fleas vary in the size and shape of their outer head covering. Suggest a reason for this.

 

Some help please? Thanks

[SocialRhubarb]

My guess would be that the head shape is varying with the seasons, or with the mating cycle, and hence is motivated by changing temperatures, changing diets or sexual selection. Different head shapes might have different properties in terms of heat loss, catching prey or finding a mate and reproducing.

[Yacoubb]

My guess would be that the head shape is varying with the seasons, or with the mating cycle, and hence is motivated by changing temperatures, changing diets or sexual selection. Different head shapes might have different properties in terms of heat loss, catching prey or finding a mate and reproducing.

I was thinking on the lines of heat loss and surface area to volume ratio of their heads affecting heat loss and containment during various seasons of the year.

Thanks!

[vox nihili]

I was thinking on the lines of heat loss and surface area to volume ratio of their heads affecting heat loss and containment during various seasons of the year.

Thanks!

With these kind of questions the answer just needs to be reasonable. I can't think of any additional ones to SocialRhubarb's, so all of them are fine I daresay! As long as you can justify it.

[Yacoubb]

DO we have to know about the Hardy-Weinberg Equilibrium?

[alondouek]

Yep! It useful to know how to calculate allele frequency etc

[Yacoubb]

Yep! It useful to know how to calculate allele frequency etc

Should we just know how to interpret a graph? Or I mean, what else should we know about it?

[alondouek]

Know how to interpret graphs to a basic extent. Understand the equation and how it can be used to calculate allele and genotype frequencies from it too

(This is what I was taught in VCE, not sure if its actually in the course - but it certainly helps in understanding population dynamics etc)

[vox nihili]

DO we have to know about the Hardy-Weinberg Equilibrium?

Absolutely do not need to know HW Equilibrium. It is not in the course.