Nucleus-Genetic Powerhouse of the Cell

Nucleus

 

The Nucleus: Genetic Powerhouse of the Cell

      Nucleus is Latin for kernel or nut, and it aptly describes this cell organelle, which holds all of the genetic material of the cell. The nucleus isn’t just responsible for holding your DNA; it also helps control cell division, carries out gene transcription, keeps chromosomes intact by packaging DNA into chromosome bundles, and they serves as the main control center of the cell.

1: What is the nucleus?

   * The nucleus is where the genetic material is stored. It's the main point of control and function within the cell.

   * The nucleus has a nuclear envelope, or a membrane that surrounds it. This membrane helps regulate what can enter and exit the nucleus.

  * There are two types of RNA in the nucleus - messenger RNA, which transports genetic information to other parts of the cell, and ribosomal RNA, which helps with protein production by creating ribosomes that build proteins from amino acids.

Nucleus

2: Major Components of Nucleus.

           The nucleus of the cell is an organelle that houses its genetic material. This means it is where your DNA is kept. The nucleolus, a major component of the nucleus, produces ribosomes (protein factories). These ribosomes help to create new cells and keep existing ones alive. Some other major components of the nucleus include: Chromatin, Nuclear envelope, laminar nuclear membrane, nucleoplasmic reticulum, perinuclear cytoplasm, centrosome/centriole and nuclear pores. The function of the chromatin, located within the nucleus, is to compact chromosomes and make them easier for a cell's machinery to access. The nuclear envelope provides a barrier between the nucleoplasm and other organelles like mitochondria in order to prevent cross-contamination. It also forms ion channels which allows some ions like potassium ions from inside or outside of the cell into or out of the cytoplasm.

Nucleus

3: The nuclear envelope and nucleocytoplasmic transport.

          The nuclear envelope is made up of two layers, each with its own set of proteins. The inner membrane, or nuclear lamina, separates the nucleus from the cytoplasm. The outer membrane, or nuclear envelope, separates the nucleus from the outside world. This double-layered barrier is also responsible for regulating what enters and leaves the nucleus through a process called nucleocytoplasmic transport.

4: Organelles in Nucleus.

          In addition to storing genetic material, the nucleus also contains a number of organelles, including ribosomes and lysosomes. Lysosomes are sacs full of enzymes that digest food in order to produce energy for the cell. Ribosomes make proteins by reading instructions from messenger RNA molecules. When they have finished their work, the ribosomes release these newly created proteins into other parts of the cell. Ribosomes form inside the nucleolus, which is another specialized organelle found only in nuclei. The nucleolus produces ribosomal RNA (rRNA), which is used as a template for making ribosomes outside of it. DNA's important role as an organism's genetic blueprint means that every nucleus has to be extremely organized if it is going to function properly. The DNA molecule coils tightly around spool-like proteins called histones, forming long structures called chromosomes.

Nucleus

5: Replication, transcription and translation in nucleus.

           Replication and transcription are processes that happen in nucleus. Replication is when a copy of DNA is made, so that there is a backup. Transcription happens when RNA is created from DNA. Translation happens when information from RNA gets translated into a protein. The nucleolus is also found in nucleus and has ribosomes for translation.

There are other things that occur in the nucleus as well, such as repair and replication of broken chromosomes (Mendeley). During replication, the old DNA is copied to make sure that all genetic material is still intact. Chromosomes can break during this process because they are very fragile (Mendeley). In order to fix this problem, there are enzymes called polymerases that fix these broken pieces of DNA. In addition to fixing chromosome breaks, polymerases create new strands by copying old strands of DNA during replication.

6:  Types of Nuclei.

           There are three main types of nuclei in cells. The first type is called a prokaryotic nucleus. This is found in bacteria and archaea. They are small, simple nuclei that contain little to no DNA. The second type is called a eukaryotic nucleus. They contain the large amount of DNA that makes up chromosomes, and they are larger than prokaryotic nuclei. Eukaryotic nuclei also have a membrane around them. Lastly, there is a type of nucleus called plastids. Plastids are found in plants and function as factories for food production.

 

7: Pathology involving nucleus.

          Pathology involving nucleus can manifest in a variety of ways depending on the type and severity. Congenital disorders are those that are present from birth, and include Down syndrome, Klinefelter syndrome, Turner syndrome, and Wolf-Hirschhorn Syndrome. These disorders often result in a decreased number of chromosomes which changes how certain organs function. For example, Klinefelter Syndrome includes possessing an extra X chromosome as well as too many Y chromosomes which can cause sterility in males and females.

Read more…… Cell Membrane,…. Cell transport,….   Cell characteristics.