This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Metabolism of nucleic acids, Subject name: Biochemistry
Histone in nucleosome core are all except 
Select and explain. 
A. H2A, B. H2B, C. H3, D. H1
D: H1
Answer: D: H1 
Explanation: In addition to binding to the nucleosome, the H1 protein binds to the "linker DNA" (approximately 20-80 nucleotides in length) region between nucleosomes, helping stabilize the zig-zagged 30 nm chromatin fiber Ref-Harpers illustrated biochemistry 30/e p280