Table of Contents
What is Nucleolus?
Nucleolus – Function:
The nucleolus is a small, dense structure within the nucleus of a eukaryotic cell. It is the site of ribosome biogenesis, the process by which ribosomes are made. The nucleolus is also the site of rRNA synthesis, the process by which ribosomal RNA is made.
History
- The nucleolus is a small, round body found in the nucleus of cells. It is made up of DNA and proteins and is responsible for the production of ribosomes. Ribosomes are the tiny structures that cells use to create proteins.
- The nucleolus was first discovered in 1883 by German scientist Walther Flemming. He observed a small, round body in the nucleus of cells and named it the nucleolus. At the time, he didn’t know what the nucleolus was responsible for.
- In the early 1900s, scientists discovered that the nucleolus was responsible for the production of ribosomes. They also discovered that the nucleolus was made up of DNA and proteins.
- Today, scientists still don’t know everything about the nucleolus. However, they do know that it plays an important role in the production of ribosomes.
RNA Structure
RNA is a single-stranded molecule made up of nucleotides. The nucleotides are composed of a sugar, a phosphate group, and a nitrogenous base. The sugar in RNA is ribose, and the four bases are adenine (A), guanine (G), cytosine (C), and uracil (U). The sequence of the bases in RNA determines the genetic information carried by the molecule.
Function of Nucleolus and Ribosome Assembly
- The nucleus is a cellular organelle that contains the genetic information of a cell.
- The nucleolus is a small organelle within the nucleus that is responsible for the assembly of ribosomes.
- Ribosomes are organelles within the cell that are responsible for the synthesis of proteins.
Key Concepts
- A nucleolus (plural: nucleoli) is a small, dense structure within the nucleus of a eukaryotic cell. It is the site of ribosome biogenesis, the process by which ribosomes are made. Ribosomes are the organelles within cells that are responsible for protein synthesis.
- The nucleolus is formed when the chromosomes condense during the early stages of mitosis or meiosis. It is composed of DNA and proteins, including the ribosomal proteins that are necessary for ribosome biogenesis.
- The nucleolus is an important part of the cell, but it is not essential for life. The absence of a nucleolus does not cause any major defects in protein synthesis, and most cells can survive without one. However, the nucleolus is important for the proper function of certain cells, such as those in the liver and bone marrow, which depend on ribosomes for their survival.