The organelle containing DNA in a cell and found in only eukaryotic cell is known as the
A plasma membrane
B ribosomes
C endoplasmic reticulum
D cytoplasm
E nucleus
The correct answer and explanation is:
The correct answer is E. nucleus.
The nucleus is the organelle responsible for containing the cell’s genetic material in the form of DNA. It is a defining feature of eukaryotic cells, which are complex cells with membrane-bound organelles. In eukaryotes, the nucleus serves as the control center for cellular activities, including growth, metabolism, and reproduction. It is enclosed by a double membrane known as the nuclear envelope, which separates the DNA from the rest of the cell’s contents, providing a protected environment for the genetic material.
Within the nucleus, the DNA is organized into structures called chromosomes. These chromosomes carry the genes that encode the information necessary for the production of proteins, which are essential for the structure and function of the cell. The process of transcription, where RNA is synthesized from DNA, also occurs in the nucleus. This RNA is then transported out into the cytoplasm, where it is used as a template for protein synthesis on ribosomes.
Unlike prokaryotic cells, which do not have a nucleus and instead have their DNA located in a region called the nucleoid, eukaryotic cells have this highly organized and compartmentalized structure. This separation allows for more complex regulation of gene expression and greater control over cellular processes.
In contrast, the other options listed do not contain DNA. The plasma membrane (A) is a lipid bilayer that surrounds the cell, providing structure and regulating the movement of substances in and out of the cell. Ribosomes (B) are responsible for protein synthesis, but they do not contain DNA. The endoplasmic reticulum (C) is involved in protein and lipid synthesis and has a network of membranes, but it does not contain DNA. Finally, cytoplasm (D) is the gel-like substance inside the cell that houses the organelles but does not contain the cell’s genetic material.