For investigation ch 9

I'm thinking the first question is easier to answer. I've copy and pasted my answer below. I'm afraid it's a little too simple. If anyone has suggestions, they'd be greatly appreciated. I'm drawing a blank on a good second method.

1. Suggest two ways in which, with the help of a microscope, one might determine the relative duration of the various phases of mitosis.

I think you can just time each phase of mitosis. I would place a cell of a specific substance, say a red blood cell, under a microscope. I would have to keep diligent watch over the cell during the entire process. Using the microscope, I would be able to see the change from interphase to prophase by waiting until individual chromosomes are visible. Then, from prophase to prometaphase I would wait how many every seconds/minutes/hours it takes for the kinetochore microtubles to appear. Once the centromeres line up in the center, I will know metaphase has been reached. From there, I would wait until the sister chromatids separate, knowing anaphase is occuring. The last step of mitosis, telophase, will have been reached once the daughter chromosomes reach the poles and the nuclear envelopes start to form. I would record the start and end time of each phase so I would know the duration of each phase as well as the duration for the entire process.

Another method I would consider would involve dying parts of the cell. I think the chromosomes should be dyed either pink/purple/or blue. After the chromosomes have been dyed, I'd follow the same process above by keeping watch and timing each phase. Dying the chromosomes would hopefully make it easier to see the chromosomes in the cell and hence notice the change in phase.

The only thing I would change in this would be instead of saying dye use the term stain it's more scientific. Also maybe reword it so you aren't using personal pronouns so much.

So it would look kind of like this:

One of the ways to do this would be to time each phase by using a microscope and a stopwatch or clock of some sort. First, place a cell of a specific substance of something that is easy to see under most microscopes, say a cheek cell, under a microscope. Watch diligently over the cell during the entire process. Using the microscope wait until individual chromosomes are visible. This is the change from interphase to prophase. Then, from prophase to prometaphase wait how many every seconds/minutes/hours it takes for the kinetochore microtubles to appear. Once the centromeres line up in the center, this shows metaphase has been reached. From there, wait until the sister chromatids separate, knowing anaphase is occuring. The last step of mitosis, telophase, will have been reached once the daughter chromosomes reach the poles and the nuclear envelopes start to form. Record the start and end time of each phase so the duration of each phase as well as the duration for the entire process is known.

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