A chromatin is DNA combined with proteins that is found in the nucleus of eukaryotic cell, It is partially compacted. A chromosome is a fully compacted chromatin that is visible in cells during nuclear division. the degree to which chromatin is compacted greaty affects the accessbility of chromatin to the cell because compaton is necessary in order to fit a very large amount of DNA into a much smaller nucleus.
Homologous chromosomes are two chromosomes with the same length, centromere position and same sequence of genes because they are the same chromosome type. Not same alleles because one maternal and one paternal, they are never attached by the centromere and appear in metaphase, so they are replicated.