BIO SCI 97 Lecture Notes - Lecture 5: Telomere, Kinetochore, Spindle Apparatus
Document Summary
Lecture 5: chromatin consists of dna and proteins, chromatin is the material of which chromosomes are composed, chromatin is only visible by light microscopy during mitosis when it condenses and compacts. The amount of compaction of dna differs from one from another. Some bubbles are larger than others in the other diagram. Even during interphase, you can see different chromosomes associated with different regions. Chromosome appear to be anchored by their centromeres. Adjacent interchromosomal domains that are dna scarce separate chromosomal territories. Active genes appear to be near these boundaries perhaps because transcription components have easier access or. Histones: histones are the major class of proteins associated with dna, there are 5 major types of histones in all eukaryotes h1, h2a, h2b, h3 and h4. 2 h3/h4 dimers assemble to form a tetramer. Once this is formed, 2 h2a/h2b dimers associate with the tetramer to form the octamer: h1 is not part of the core nucleosome.