Biology · Chromosomes and DNA
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The following histone proteins form a nucleosome complex except:
- A
H1
- B
H2A
- C
H2B
- D
H3
The nucleosome is the fundamental structural unit of chromatin in eukaryotic cells. It comprises a histone octamer around which DNA is wrapped. This octamer consists of two copies each of four core histone proteins: H2A, H2B, H3, and H4. Histone H1, on the other hand, is not part of the core nucleosome particle. Instead, H1 is associated with the linker DNA between nucleosomes, playing a role in compacting the chromatin structure into higher-order formations. Therefore, the correct answer is H1, as it does not form part of the nucleosome core.
Histone H1 is not part of the nucleosome core particle; it is involved in the higher-order structure of chromatin.
Histone H2A is a core histone protein that forms part of the histone octamer in the nucleosome.
Histone H2B, like H2A, is also a core histone protein and part of the nucleosome structure.
Histone H3 is another core histone protein, integral to the nucleosome, and pairs with histone H4.
Tagged under Biology · Chromosomes and DNA · 2019