BIOL239 Lecture Notes - Lecture 5: Prophase, Centrosome, Spermatozoon
Document Summary
The chromosomes resemble a mass of extremely fine tangled string called chromatin surrounded by the nuclear envelope . Each convoluted thread of chromatin is composed mainly of dna (which carries the genetic information) and protein (which serves as a scaffold for packaging and managing that information. One particularly important part of this activity is the accurate duplication of all the chromosomal material. The chromatin condenses into discrete threads, and then each chromosome compacts even further into the twin rods clamped together at the centromere that can be identified in karyotype analysis . Each rod in a duo is called a chromatid ; as described earlier, it is an exact duplicate of the other sister chromatid to which it is connected. Continued observation would reveal the doubled chromosomes beginning to jostle around inside the cell, eventually lining up at the cell"s midplane.