Eukaryotic Chromosomes

             chromosome.gif (941 bytes)         
               A chromosome is the entire strand of a chromatid
           DNA is packed and coiled into chromosomes               

                centrome.gif (497 bytes)
A chromosome's  centromere is the center
of the chromosome where duplicated chromatids are attached.


A nucleosome is the structural unit of a eukaryotic chromosome.  It is composed of histones and DNA. 
are proteins that form the core of the nucleosome.

nucleosome.gif (996 bytes)

chromatid.gif (756 bytes)
A chromatid is the individual half of a "duplicated" chromosome.

      chromatin.gif (559 bytes)
           Chromatin is a coiled, looped chain of nucleosomes. 
  It is the complex of DNA and proteins in a chromosome.


centriole.gif (311 bytes)                
Centrioles are microtubule structures that serve as attachment points in mitosis.  Two centrioles make up a centrosome.             


                 centrosome.gif (377 bytes)
             A centrosome is composed of two centrioles.
Centrosomes are used in mitosis to help organize chromosomal movement.