TBR Bio II chapter 10 passage 8- genetics expression

[bluequestions]

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Hey guys, so below is a question from the genetics expression chapter of TBR. I kind of get the question but I'm still a bit confused about the wording used. Can you guys help me out? Thank you so much!

49. In several types of secretory cells found in fly larvae, all the homologous chromosome copies remain side by side, creating a giant polytene chromosome. In the salivary glands of Drosophila larvae, each of the four chromosomes has been replicated through ten cycles without separation of the daughter chromosomes. How many identical strands of chromatin are lined up side by side?

A. 128
B. 256
C. 512
D. 1024

Answer: D

My question is: when they are saying "without separation of the daughter chromosomes", I can't imagine the replication process, can someone describe it please? Also, when they ask for the "strands of chromatin", are they referring to dsDNA or ssDNA? (is chromatin just a less packed version of chromosome?)

Thanks!

 

[Siromas]

Here's my take on it:

- I've been told that chromatin = DNA + protein. It comes in the form of euchromatin (less compact) and heterochromatin (condensed) forms

-By saying "without separation of the daughter chromosomes", the solution is 2^10. If they had said there was separation, then I think the answer would have been 4^10.

When sister chromatids are still attached to each other during replication, they together count as one single chromosome in total.

I could also be 100% wrong. Hopefully someone else can chime in