BIO 2133 Study Guide - Cellular Stress Response, Interphase, Polyploid
Document Summary
A study of the induction of polytene chromosome puffing by heat shock treatment in. The structures labeled b indicate bands whilst structures labeled i indicate interbands. The scale bar is 12 m for both a and b. Questions: describe the observed difference(s) between the structures of polytene chromosomes with and without heat shock treatment? (2 marks) Polytene chromosomes that have undergone heat shock treatment exhibit strands with localized uncoiling, otherwise known as puffs. This indicates an increase in genetic activity where rna is produced by genes involved in highly active transcription of dna: give three biological processes or phenomena"s that were discovered through the study of polytene chromosomes? (3 marks) It was found that the steroid hormone called ecdysone exerts its action through gene activation through studies of sequential puff formation in polytene chromosomes. As larva, fruit flies increase their size by ingesting large amounts of food.
