BIOL 366 Lecture Notes - Lecture 4: Polytene Chromosome, Uterus, G1 Phase
12 Feb 2018
School
Department
Course
Professor
Document Summary
Signal sequences tell where the yellow crescent needs to go. Need a sorting system that is going to direct traffic. The process by which cells become different from one another based upon the unique combination of genes that are active or expressed. Diff genes diff proteins differentiation of diff cell types (1) every somatic cell nucleus of an organism contains the ocmpelte genome established in the fertilzied egg. Gene expression can be regulated at four levels: differential gene transcription, selective nuclear rna processing, selective messenger rna, differential protein modification. Identical cytological maps: temporal and/or cellular activation of different regions, the dna of certain larval tissues undergoes numerous rounds of dna replication without separation such that the structure of the chromosomes can be seen. In polytene chromosomes, no structural differences were seen between cells, however, different regions of the chromosomes were puffed up at different times and in different cell types, which suggested that these areas were actively making rna.
