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Chromatin, Chromatid, Chromsome Terminology - (Apr/02/2009 )

Some Questions to which I have found different/conflicting answers depending on what I have read or who I have talked to. Thanks in Advance.

1-Chromatin, chromosomes, and chromatid all consist of DNA AND some sort of proteins?
2-Is the following statement accurate: ALL types/forms of chromatin material and chromatids consist of chromosomes BUT not all types of chromosomes are chromatin or chromatids?
3-An unreplicated chromosome consists of a single strand of DNA?
4-An unreplicated chromosome is considered a chromosome, but are two sister chromatids attached by a centromere considered a SINGLE chromosome or TWO chromosomes?
5-Chromatid refers to a SINGLE chromosome/DNA strand in the complex of the two DNA strands/chromosomes which are attached? Can the whole complex be considered A chromatid or TWO chromatids; do you use the term sister CHROMATID or CHROMATIDS to describe the entire structure?
6-The term chromatid(s) is ONLY appropriate when two DNA strands/chromosomes are attached at the centromere?
7-When cells are not replicating, the DNA is still in chromosome form. However it is very loose and hard to see. Is the term chromatin used for a SINGLE stretched out chromosome or ALL stretched chromosomes?
8-Can the term homologous chromosomes be used to describe the two chromosomes joined by a centromere? Can the term homologous chromosomes be used to describe the two copies (i.e. two strands) of chromosome 1 that a human carries?
9-In a human male, can you consider the X and Y chromosomes to be homologous OR can you only consider the X chromosome to be homologous when it is attached to its sister chromatid during mitosis/meiosis?
10-There are two centromeres and two kinetechores for sister chromatids. However there is one centromere region?


So what answers make sense to you? Have you tried your text book? They are pretty reliable usually.


You need one good textbook with nice figures.