Question 11

DNA is stored in the nucleus.

DNA is primarily stored in the nucleus of eukaryotic cells, where it is organized into chromosomes. This central location acts as a control center for cellular activities and gene expression.

A) The nucleus

This option is correct because the nucleus is the membrane-bound organelle in eukaryotic cells that houses the cell's genetic material, DNA. It serves as the site for DNA replication and transcription, making it essential for cellular function and heredity.

B) Ribosomes

Ribosomes are not the storage site for DNA; instead, they are the cellular machinery responsible for protein synthesis. While ribosomes do play a crucial role in translating the genetic information carried by mRNA, they do not contain or store DNA.

C) Endoplasmic reticulum

The endoplasmic reticulum (ER) is involved in the synthesis of proteins and lipids but does not store DNA. It functions as a network of membranes that help in the processing and transport of biomolecules, but the genetic material remains in the nucleus.

D) Mitochondria

Mitochondria contain their own small amount of DNA, which is distinct from the nuclear DNA, but they do not serve as the primary storage location for DNA in a cell. Instead, they are primarily known for their role in energy production through cellular respiration.

Conclusion

The nucleus is the definitive location for DNA storage in eukaryotic cells, as it provides a controlled environment for DNA replication and transcription. Other options, such as ribosomes, endoplasmic reticulum, and mitochondria, serve different cellular functions and do not act as the main repository for genetic information.