Question

question 62
which of the following statements correctly describes one characteristic of histones?

each nucleosome consists of two histones.
each nucleosome consists of eight histones.
the carboxyl end of each histone extends outward from the nucleosome and is called a \histone tail.\
histones are found in mammals but not in other eukaryotes.

Explanation:

1. Analyze the first option: A nucleosome consists of a core particle with eight histones (two each of H2A, H2B, H3, H4), so "two histones" is incorrect.
2. Analyze the second option: Each nucleosome core particle is made of eight histones (two copies of H2A, H2B, H3, H4), so this is correct.
3. Analyze the third option: The amino - terminal end of histones extends outward as the "histone tail", not the carboxyl end, so this is incorrect.
4. Analyze the fourth option: Histones are present in all eukaryotes, not just mammals, so this is incorrect.

Answer:

B. Each nucleosome consists of eight histones. (Here we assume the second option is labeled as B, if the original options have different labels, adjust the label according to the actual situation. The key is the statement "Each nucleosome consists of eight histones" is the correct description of histones.)