What is the form of chromatin that generally contains less active genes?

Heterochromatin is the form of chromatin that is typically associated with less active genes. It appears as a denser, more compact structure compared to euchromatin, which is more loosely packed and contains actively expressed genes. Heterochromatin is generally found at the periphery of the nucleus and is involved in maintaining structural integrity of the chromosome.

The genes located in heterochromatin are often transcriptionally inactive or have reduced levels of expression due to their tightly packed nature, which restricts access for the transcription machinery. This form of chromatin plays essential roles in processes such as gene regulation, chromosome segregation during cell division, and protecting chromosomal integrity.

In contrast, euchromatin not only contains the active genes but is also more accessible for gene expression. Nucleosomes are the fundamental units of chromatin composed of DNA wrapped around histone proteins and do not directly indicate gene activity by themselves. Chromatids are the replicated forms of chromosomes and are involved in cell division, rather than describing the state of chromatin related to gene activity.