The Animal or eukaryotic cells Are the type of cells that form all the tissues of animals. Its main characteristics are a well differentiated nucleus and a nuclear membrane.
Eukaryotic cells are distinguished mainly from prokaryotic cells in that they do not possess cell walls or chloroplasts. Prokaryotic cells are those that form the plant kingdom. In addition, the plant cells have a larger diameter than the eukaryotic cells of the animals.
Parts of the eukaryotic or animal cell.
We can divide the eukaryotic cell into three large parts; The cell envelope, the Cytoplasm and nucleus.
In the cellular envelope we find the cell membrane and the plasma membrane. The cytoplasm is formed by cellular organelles such as mitochondria, lysosomes, etc. The nucleus is formed by the nuclear membrane and nucleoplasm.
Parts and main functions of an animal cell
Core
It is the most important part of the cell. It functions as the brain of the cell dictating the instructions for the biological actions performed by the cell. The nucleus is an organelle since it is found within the cytoplasm and occupies up to 10% of the cell.
Within the nucleus of the cell is the deoxyribonucleic acid, where the genetic information of the cell is contained.
Inside the nucleus is contained the nucleolus. A supra-macromolecular structure that transcribes ribosomal RNA.
Cellular or plasma membrane
The cell membrane is the layer that envelops the cell and separates it from the outside. It is a semipermeable membrane composed of phospholipids.
This membrane helps the cell to relate to the outside, and has pores and channels through which nutrients access and the waste is expelled from the cell.
Cytoplasm
It is the gelatinous liquid that forms the cell and where all the organelles float. Inside the cytoplasm is a substance called cytosol where molecules float.
Endoplasmic reticulum
This internal support is a cluster of channels and interconnected bags that are surrounded by a membrane. In the production, storage and transport of some substances. We can divide it in two; The rough endoplasmic reticulum and the smooth endoplasmic reticulum.
The rough endoplasmic reticulum predominates in the cells responsible for exporting proteins. It is called rough because of the appearance it has in the microscope because it has many ribosomes attached to its membrane.
In contrast, the smooth endoplasmic reticulum is one that synthesizes the lipids of the cell membrane. It is the continuation of the cisternae of the rough endoplasmic reticulum.
It also participates in lipid synthesis, detoxification and glycogenolysis. Another function is to store calcium in the cells.
Ribosomes
The ribosomes of eukaryotic cells are formed in the nucleus, but they develop their function of synthesis in the cytosol.
They are responsible for synthesizing proteins with information from the DNA that arrives in the form of messenger RNA.
The synthesis of proteins that perform ribosomes act on the cytosol, but may also appear associated with the rough endoplasmic reticulum where they synthesize the proteins for their excretion.
Mitochondria
In these organelles the breathing of the cell takes place. This process forms the Adenosine Triphosphate (ATP), which is the main molecule that gives energy to the cell. It is the power plant of the cell.
In the mitochondrial matrix there are some actions necessary for life such as the Krebs cycle, beta-oxidation of fatty acids and amino acids, and urea and some heme groups are synthesized.
Golgi apparatus
He Golgi apparatus Is in charge of receiving the lipids and proteins and collects the waste that will be expelled from the cell. It is formed by dictiosomas that in turn are composed by saccals or cisterns.
Among its functions is glycosylation of proteins, glycosylation of lipids and distribution of lysosomes and peroxisomes.
The Golgi apparatus is usually larger in cells that continuously secrete substances, such as antibody-excreting cells.
Lysosomes
Part of a cell, including lysosome
The Lysosomes Are responsible for the absorption of substances that reach the cells. They also take care of getting rid of waste that the cytoplasm does not want.
It fulfills the function of protecting the cell from foreign bodies that want to invade it. They contain hydrolytic and proteolytic enzymes to digest the external materials that reach the cell.
If the enzymes accumulated in the lysosomes were released, they would kill the cell. That is why lysosomes have a membrane to protect the cell from these enzymes.
Peroxisomes
They are cytoplasmic organelles that contain oxidases and catalases. They are stores of enzymes necessary to make metabolic reactions.
Vesicle
Vesicles are organelles that store, transport, or digest cellular debris. In the process of metabolizing the cell are an essential element. They are created in the Golgi apparatus and in the rough endoplasmic reticulum.
Centrosoma
They are cellular organelles that are not surrounded by a membrane. It consists of two centrioles embedded in a set of protein aggregates.
Generally speaking they are known as microtubule computers. They are very necessary since in the processes of mitosis they form the mitotic spindle that is necessary to create new cells from the stem cell.
Scourge and cilia
They are appendage structures of parts of the cell. The most studied scabs are those of spermatozoa. These push the sperm and are designed to get one of them to reach the cell.
In contrast to cilia that seek the coordination of cells on a cell surface. They have a movement reminiscent of rowing, with cyclic movements.
References
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