In eukaryotic cells, chromosomes consist of DNA and what other component?

In eukaryotic cells, chromosomes consist of DNA and what other component?

• A. RNA
• B. Proteins called histones
• C. Enzymes
• D. Carbohydrates

Answer: (B)

Chromosomes in eukaryotic cells are primarily composed of DNA and proteins called histones. Histones play a crucial role in the organization and compaction of DNA within the nucleus. They act as spool-like structures around which DNA winds, facilitating the highly structured packaging necessary for DNA to fit within the cell nucleus. This chromatin structure not only helps in the efficient storage of genetic information but also plays a significant role in gene regulation, as the degree of DNA compaction can influence gene accessibility for transcription. Histones are modified through various chemical tags that can enhance or inhibit gene expression, linking them directly to the regulation of cellular processes. This cooperative interaction between DNA and histones is fundamental to maintaining chromosomal integrity during cell division and ensuring proper gene expression. In contrast, while RNA plays a role in translating genetic information, enzymes are responsible for biochemical reactions, and carbohydrates serve different structural and energy-related purposes within the cell, they do not comprise the primary structure of chromosomes in eukaryotic cells. Thus, the correct association of histones with DNA underscores the essential nature of these proteins in chromosome structure and function.

Chromosomes in eukaryotic cells are primarily composed of DNA and proteins called histones. Histones play a crucial role in the organization and compaction of DNA within the nucleus. They act as spool-like structures around which DNA winds, facilitating the highly structured packaging necessary for DNA to fit within the cell nucleus. This chromatin structure not only helps in the efficient storage of genetic information but also plays a significant role in gene regulation, as the degree of DNA compaction can influence gene accessibility for transcription.

Histones are modified through various chemical tags that can enhance or inhibit gene expression, linking them directly to the regulation of cellular processes. This cooperative interaction between DNA and histones is fundamental to maintaining chromosomal integrity during cell division and ensuring proper gene expression.

In contrast, while RNA plays a role in translating genetic information, enzymes are responsible for biochemical reactions, and carbohydrates serve different structural and energy-related purposes within the cell, they do not comprise the primary structure of chromosomes in eukaryotic cells. Thus, the correct association of histones with DNA underscores the essential nature of these proteins in chromosome structure and function.