Phases You Can't See with Spindle Inhibition

[nobahar]

Hello!

Homework Statement

If a chemical is used to inhibit spindle formation, what phases would you not see [under a microscope]?
2. Possible answers
Prophase
Prometaphase
Metaphase
Anaphase
Telophase

The Attempt at a Solution

I figured prometaphase, metaphase and anaphase.
I know some people don't use prometaphase, by this phase I don't mean prophase. Instead I mean the stage in which the connection of the micotubules with the kinetochores begins to occur, and there is the 'back and forth' movement to attempt to align the chromosomes along the metaphase plate (when this occurs it is obviously metaphase). However, apparently I'm wrong and prometaphase isn't one. There's supposed to be three answers. I guess the other is going to be telophase, but I can't see how prometaphase can be ruled out...
Thanks in advance.

 

[Ygggdrasil]

You would probably observe the first parts of prometaphase (e.g. disappearance of the nuclear envelope) but because spindle formation could not occur, you could not progress to the end of prometaphase and into metaphase.

 

[nobahar]

Thanks for the reply,
I think that what you have said supports my thinking, since important stages of prometaphase cannot be complete, then I would say that it is perfectly reasonable to suggest that this particular stage would not be observable. Very peculiar, but, I suppose that if early prometaphase can be observed then strictly this does indeed count. A little annoying.
Thanks.

 

[Kushal]

i may be wrong but i think that you would see up to metaphase. because, if i remember my biology well, the chromatids will line up at the equator of the cell. It is only in anaphase that the spindle come into action to pull apart the sister chromatids to opposite poles. the absence of spindles will not prevent the chromatids to line up during metaphase!

 

[Ygggdrasil]

No. The spindle is required to align the chromosomes up at the metaphase plate.

 

[nobahar]

I was thinking of it from the point of view that the microtubules as they 'reach' out, and the asters, are what constitute the spindle structure. Perhaps it only counts as a spindle structure once the chromosomes are aligned along the metaphase plate. I'll find some sources and check back, if anyone else is interested... unless someone else already knows.