How to draw cell cycle 2?

What might be the outcome of the cell cycle if the chromosomes will not change structure?

• 1.) What might be the outcome of the cell cycle if the chromosomes will not change structure? 2.) With all the chemicals the body takes in everyday both good and bad, what might be the effect of these in the cell cycle and the chromosomes? 3.) Why are there different structures of chromosomes as the cell undergo the cell cycle?

• Answer:

  If i understand what you mean by "change structure" then: 1. If the chromosomes cannot unravel into euchromatin then transcription cannot take place. This would result in cell death due to the cell's inability to transcribe necessary proteins. This would also stop the cell cycle at S phase because DNA that is tightly coiled (heterochromatin) cannot be replicated. 2. Depends greatly on what chemical and in what dose. Some chemicals can intercalate into the DNA and prevent transcription with similar effect to those listed above. Drugs that treat cancer, for example, generally prevent cells from diving. 3. During G0, G1, M, and G2, most of the DNA is tightly packed - heterochromatin - with only those regions necessary for transcription being uncoiled into euchromatin. During S phase more of the DNA is in the form of euchromatin because it is actively being replicated.