Question

Which of the following is true regarding heterochromatin in a typical mammalian cell?

A. About 1% of the nuclear genome is packaged in heterochromatin.
B. The DNA in heterochromatin contains all of the inactive genes in a cell.
C. Genes that are packaged in heterochromatin are permanently turned off.
D. The different types of heterochromatin share an especially high degree of compaction.
E. Heterochromatin is highly concentrated in the centromeres but not the telomeres.

Answer 1

Heterochromatin contains permanently turned off genes in a mammalian cell, but it is not highly concentrated in the centromeres.

Step-by-step explanation:

In a typical mammalian cell, all of the statements regarding heterochromatin are true except for option A. Heterochromatin contains genes that are not expressed, therefore, option B is true. The genes that are packaged in heterochromatin are generally in a permanently turned off state, making option C true. Different types of heterochromatin do share a high degree of compaction, thus option D is true. However, heterochromatin is not highly concentrated in the centromeres but it is concentrated in the telomeres, making option E false.