Somatic cells: Definition & Examples
The somatic cells are those that form all the tissues and organs of the body of multicellular organisms, in distinction from sexual or germ cells ( gametes ) and ES 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.
Thus, the genetic material of all somatic cells is necessarily identical. In contrast, sex cells or gametes have unique genetic content, due to the random nature of genetic recombination during its creation, which represents only half of the individual’s total information.
In fact, the cloning technique consists of taking advantage of this total genetic load present in any cell in the body of a living being, something impossible to do with 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, the chest, and even the heart. These cells are characterized by having a great elasticity that allows them to stretch and recover their original shape, thus allowing movement and strength.
- Epithelial cells. They cover the inside and outside of the body, forming a mass called the epithelium or epidermis, which includes certain segments of the skin and mucosa. Protects the body and organs from external factors, often secreting mucus or other substances.
- Erythrocytes (red blood cells). Devoid of nucleus and mitochondria in humans, these blood cells are provided with hemoglobin (which attributes the red color to the blood) to transport vital oxygen to the different reaches of the body. Many other species have nucleated red blood cells, like birds.
- Leukocytes (white blood cells). Protective and defense cells of the organism, in charge of dealing with external agents that could be causing disease or infections. They normally operate by phagocytizing 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 the spinal cord and the various nerve endings, are in charge of transmitting the electrical impulses that coordinate the body’s muscles and other vital systems. They form gigantic neural networks from the connection of their dendrites.
- Thrombocytes (platelets). Cytoplasmic fragments, more 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.
- Walking sticks or rods. Cells present in the retina of the mammalian eye and that fulfill photoreceptor roles, linked to vision in low light conditions.
- Chondrocytes. They are a type of cell that integrates cartilage, where they produce collagen and proteoglycans, substances that support the cartilage matrix. Despite being vital for the existence of cartilage, they make up just 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 organism.
- Plasmocytes. They 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 protein order necessary to identify bacteria, viruses, and foreign bodies present in the body.
- Adipocytes. The cells that make up adipose tissue (fat) are capable of storing large amounts of triglycerides inside them, practically turning into a drop of fat. These lipid reserves are used when blood glucose levels decrease and it is necessary to go to the energy reservoirs to continue with the body’s functions. Of course, accumulated in excess, these fats can represent a problem by themselves.
- Fibroblasts. Connective tissue cells, 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 connective fibers.
- Megakaryocytes. These large cells, with various nuclei and branches, integrate the hematopoietic (blood cell-producing) tissues of 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 color to the skin and defends it against sunlight. 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 pulmonary surfactant: a substance that reduces alveolar tension in the lungs during expulsion from the air, and that also fulfills immunological roles.
- Sertoli cells. Located in the seminiferous tubes of the testicles, they provide metabolic support and support to the cells responsible for the production of sperm. They secrete a good amount of hormones and substances linked to the preparation of gametes and control the function of Leydig cells.
- Leydig cells. These cells are also located in the testicles, 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 help to neurons. Its role is to control the ionic and biochemical state of the microcellular environment, defending the correct process of neural electrical transmission.