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Chromosome Separation in M Phase

• The mitotic spindle is responsible for separating duplicated eukaryotic chromosomes during the M phase of the cell cycle.

Functions of Histone Proteins

• Histones are proteins that help package DNA into structural units called nucleosomes.
• They play a role in gene regulation, DNA repair, and maintaining chromosomal stability.
• A common misconception is that a certain function might be related to genetic information transfer, which is NOT a function of histones.

Nucleosomes in Chromosomes

• Nucleosomes are not exclusive to mitotic chromosomes; they are found in all eukaryotic chromosomal structures during various phases of the cell cycle, facilitating DNA packaging.

Histone Code Function

• The histone code refers to the post-translational modifications of histone proteins that influence chromatin structure and gene expression.
• It plays a critical role in determining how tightly the DNA is wrapped around histones, thereby regulating access to the genetic information.

Composition of Human Chromosomes

• Each human chromosome is composed of DNA wrapped around histone proteins, forming nucleosomes.
• In humans, there are 46 chromosomes, consisting of 23 pairs, with a total of around 3 billion base pairs of DNA.

Role of ATP in Chromosome Segregation

• ATP is crucial for the function of motor proteins that facilitate chromosomal movements.
• It provides the energy needed for the assembly and function of the mitotic spindle apparatus during chromosome segregation.