The somatic cells are those that constitute the totality of the tissues and organs of the body of multicellular organisms, in distinction from sexual or germ cells (gametes) and embryonic cells (stem cells). All the cells that make up the tissues, organs and those that circulate in the blood and other non-reproductive fluids are, in principle, somatic cells. For instance: epithelial cells, neurons, adipocytes.
This distinction consists not only in the specificity of their functions, but also in the fact that somatic cells are of diploid type, that is, they contain two series of chromosomes in which the total of the individual’s genetic information is found.
Thus, the genetic material of all somatic cells is necessarily identical. Instead, the sex cells or gametes they have a unique genetic content, due to the random nature of genetic recombination during their creation, which represents nothing more than half of the total information of the individual.
In fact, the technique of cloning consists of taking advantage of this genetic load total present in any cell of the body of a living being, something impossible to do with a sperm or an egg, since they depend on each other to complete the genetic information of a new individual.
Examples of somatic cells
- Myocytes. This is the name given to the cells that make up the various muscles of the body, both the extremities and the thorax and even the heart. These cells are characterized by having great elasticity that allows them to stretch and regain their original shape, thus allowing movement and strength.
- Epithelial cells. They cover the internal and external face of the body, forming a mass called epithelium or epidermis, which comprises certain segments of the skin and mucous membranes. It protects the body and organs from external factors, often secreting mucus or other substances.
- Erythrocytes (red blood cells). Lacking the nucleus and mitochondria in humans, these blood cells are supplied with hemoglobin (which gives the blood its red color) to transport vital oxygen to various parts of the body. Many other species have red blood cells with a nucleus, like birds.
- Leukocytes (white blood cells). Protective and defense cells of the organism, in charge of dealing with external agents that could cause disease or infections. They normally operate engulfing foreign bodies and allowing their expulsion through the different excretion systems, such as urine, feces, mucus, etc.
- Neurons. The nerve cells that make up not only the brain, but also the spinal cord and the different nerve endings, are responsible for the transmission of electrical impulses that coordinate the body’s musculature and other vital systems. They form gigantic neural networks from the connection of their dendrites.
- Thrombocytes (platelets). Cytoplasmic fragments, rather than cells, irregular and without a nucleus, are common to all mammals and play vital roles in growth and in the formation of thrombi or clots. Its deficiency can result in bleeding.
- Canes or cotton buds. Cells present in the retina of the mammalian eye and which fulfill photoreceptor roles, linked to vision in low light conditions.
- Chondrocytes. They are a type of cell that integrates cartilage, where they produce collagens and proteoglycans, substances that support the cartilaginous matrix. Despite being vital for the existence of cartilage, they make up only 5% of its mass.
- Osteocytes. The cells that form the bones together with the osteoclasts, come from the osteoblasts and allow bone growth. Unable to divide, they play a vital role in the segregation and reabsorption of the surrounding bone matrix.
- Hepatocytes. These are the cells of the liver, filter of the blood and of the organism. They form the parenchyma (functional tissue) of this vital organ, secreting the bile necessary for digestive processes and allowing the different metabolic cycles of the body.
- Plasma cells. These are immune cells, such as white blood cells, which are distinguished by their large size and because they are responsible for the secretion of antibodies (immunoglobulins): substances of a protein order necessary to identify bacteria, viruses and foreign bodies present in the body.
- Adipocytes. The cells that form adipose tissue (fat) are capable of storing large amounts of triglycerides inside, practically becoming a drop of fat. These lipid reserves are used when blood glucose levels decrease and it is necessary to go to energy reservoirs to continue with the body’s functions. Of course, accumulated in excess, these fats can represent a problem by themselves.
- Fibroblasts. Cells of the connective tissue, which structure the interior of the body and provide support to the various organs. Its heterogeneous shape and characteristics depend on its location and activity, vital in tissue repair; but in general lines they are cells of renewal of the conjunctive fibers.
- Megakaryocytes. These large cells, several nuclei and branches, make up the tissues hematopoietic (blood cell producers) from the bone marrow and other organs. They are responsible for producing platelets or thrombocytes from fragments of their own cytoplasm.
- Macrophages. Defensive cells similar to lymphocytes, but generated from monocytes produced by the bone marrow. They are part of the first defensive barrier of the tissues, engulfing any foreign body (pathogen or waste) to allow its neutralization and processing. They are vital in the processes of inflammation and tissue repair, ingesting dead or damaged cells.
- Melanocyte. Present in the skin, these cells are responsible for the production of melanin, a compound that gives the skin its color and defends it against the sun’s rays. The intensity of the skin pigment depends on the activity of these cells, so their functions vary according to race.
- Pneumocytes. Specialized cells found in the pulmonary alveoli, vital in the production of lung surfactant: substance that reduces the alveolar tension in the lungs during the expulsion of air and that also fulfills immunological roles.
- Sertoli cells. Located in the seminiferous tubes of the testes, they provide metabolic support and support to the cells responsible for the production of sperm. They secrete a good amount of hormones and substances related to the preparation of gametes and control the function of Leydig cells.
- Leydig cells. These cells are also located in the testes, where they produce the most important sex hormone in the male body: testosterone, necessary for the activation of sexual maturity in young individuals.
- Glial cells. Cells of the nervous tissue that provide support and aid to neurons. Its role is to control the ionic and biochemical state of the microcellular environment, defending the correct process of neural electrical transmission.