Man is the most complex living organism. Its organ systems have a complex structure and are optimized for survival on land. The brain and the entire nervous system allow a person to evaluate information about the environment in which he is adapted to life. All other systems are responsible for life and movement, which is an integral property of any animal.
Scientific approach
A science that studies the features of the morphological structure of the human body is called anatomy. It distinguishes the internal structure of man and the external, general laws of the parameters of organs and body parts, development in the embryonic period. Pathological anatomy is the direction of this field of knowledge, which studies the structure of the body of an abnormal nature. Both of these sciences are very important for biology and practical medicine.
It is noteworthy that one of the methods of anatomy is the study of the structure of organs in sectional research. Such measures have been implemented only for the past 150 years, since until this time, autopsy was almost never practiced and was considered a crime. Now the autopsy of the deceased is a necessary component of the development of medical science. This allows you to optimize diagnostic and therapeutic methods.
The second science that provides a wealth of information about the structure of human organs is histology. She studies the internal structure of a person at the micro level, that is, under a microscope. Cytology and immunochemistry are methods for studying cells.
Morphology characterization
The internal structure of the human body has many similarities with the anatomy of animals of the mammalian class. This is due to the fact that from the point of view of evolutionary theory, man is a mammal. It developed in parallel with other representatives of this class and has similarities with them in the structure of the body and in the cellular structure. In addition, even at the genetic level, humans and other mammals are very similar.
General body concept
In anatomy, the external and internal structure of a person does not stand out in different directions. There is only anthropometry and the doctrine of internal organs, nerves, blood vessels, ligaments, muscles and bones. The structure of the skin is considered in histology and neurology. The very structure of man is simple and easy to reproduce.
The elementary unit of living in the body is the cell. The accumulation of cells with the same functions and structure is called tissue. Several tissues form organs that combine into systems. Therefore, the body should be represented as a system of organs whose functions are balanced.
Human organ systems
They form the whole organism and are responsible for the vital functions of the body. In turn, organs are made up of tissues, and tissues are made up of cells of the same type. Moreover, the body consists of the following systems:
- musculoskeletal;
- digestive
- respiratory
- Nervous
- cardiovascular;
- urinary;
- sexual
- coverslip;
- endocrine.
Studying the internal structure of the human body, it is impossible to distinguish the main and secondary system. All of them are important in their own way, and, functioning together, provide the vital activity of the whole organism.
The structure of the musculoskeletal system
This system of organs is responsible for the movement and maintenance of body position. It consists of the skeleton, ligaments and joints, muscles. Bone is a complex organ consisting of organic matter (proteins) and inorganic (hydroxyapatite). This is a living body structure, unable to move independently. Ligaments and joints are responsible for connecting bones. Also, some of them can connect as a result of complete intergrowth. An example is the fusion of the pelvic bones (pubic, sciatic, and iliac). This method of bone connection is called synostosis.
The active organ of the musculoskeletal system is muscle. It has a fibrous structure. The muscle is covered with fascia, and the tendon is attached to the bone. Its contraction drives the bones connected in the joints. These changes in bone position allow the body to move. At the same time, signals about movement are supplied by the brain and sent to the muscles along the nerves.
Digestive system
This is one of the most complex systems, which includes many organs. They are divided into parenchymal (liver and others) and hollow (the entire intestinal tube). The whole system consists of the oral cavity with its organs (teeth, tongue, salivary glands), pharynx, esophagus, stomach, small and large digestive glands and intestines.
The oral cavity is the initial section of the digestive tract. This is a hollow organ that serves to capture food and grind it with teeth, as well as to wet saliva. The pharynx and esophagus are pathways for partially processed foods that must first enter the stomach.
In the stomach, preparations are underway for the complete breakdown of food, which should occur in the intestine. It begins with the duodenum 12, continues with the skinny and ileum, and ends with the large intestine. In the duodenum 12, food must be completely processed by enzymes, and in the skinny one all food substances must be absorbed. Only the part of food that a person cannot digest due to a lack of digestive enzymes enters the large intestine.
The most important role in digestion is played by the liver and pancreas. The latter secretes enzymes for the breakdown of carbohydrates and proteins, while the liver is needed for the secretion of bile acids, which can complete the processes of emulsification of fats and activate pancreatic enzymes.
After the absorption of the food components is complete, the food moves to the large intestine. There is an optional microflora, necessary for the breakdown of cellulose and pectin. Bacteria synthesize vitamins from these substances. In the large intestine, they are absorbed together with water (water-soluble) or directly penetrate the intestinal wall (fat-soluble). The digestive system ends with the rectum, through which all undigested food residues are removed.
Respiratory and cardiovascular systems
The internal structure of a person, the scheme of which is represented by tissues, organs and organ systems, cannot exist without blood circulation and respiration. These two systems are interconnected. Therefore, it is advisable to consider them together.
The respiratory system is formed by hollow organs: the respiratory tract (nasal cavity, nasopharynx, oropharynx, larynx, tracheobronchial tree) and lungs. Each lung surrounds the pleura.
The functions of the respiratory system are blood oxygenation and carbon dioxide removal. Also, various sections of the respiratory tract play auxiliary roles: warming and moisturizing the incoming air. In this case, the lungs also participate in the regulation of the acid-base equilibrium of the plasma (due to the removal of carbon dioxide).
The cardiovascular system performs a transport function, delivering oxygen associated with hemoglobin to the tissues. It also receives nutrients: amino acids, fatty acids, glucose. The cardiovascular system is represented by the heart, arteries, arterioles, capillaries, venules, veins, lymph vessels and nodes.
Nervous and endocrine systems
The nervous system plays the role of a regulator of body functions. The internal structure of a person, whose photos give a visual representation of the structure of our body, cannot be considered separately from the nervous and humoral systems. They are just as important as the others. The nervous system is represented by the brain and spinal cord, nerve endings and nerves. These structures are responsible for almost all functions, giving "orders" to other organ systems.
The endocrine system also plays the role of a regulator of functions and biological processes. She is responsible for growth, reproduction, metabolism. Regulation of these processes occurs due to the release of hormones. The entire endocrine system is represented by individual glands, the activity of which is controlled by the pituitary gland. It secretes vasopressin, oxytocin, tropic hormones, and release factors. Vasopressin regulates the amount of fluid in the body, and oxytocin - uterine contractions during labor.
Tropic pituitary hormones are signals for other endocrine glands (thyroid and adrenal glands). Release factors are substances through which the function of the hypothalamus is regulated. The latter is a brain structure.
Urinary and reproductive systems
The urinary system is represented by the kidneys with the urinary tract (ureters, urinary bladder, urethra). In men, it is inextricably linked with the genitals (testes, spermatic cord, seminal vesicles, prostate). In women, the functioning of both systems has fewer similarities. In their body, the urethra is not connected to the reproductive system, represented by the uterus, ovaries, vagina and labia.
The ovaries in women and the testes of men are glands that have two types of secretion: internal and exocrine. These are glands of mixed secretion involved in the formation of germ cells and the regulation of the functions of the reproductive system. Moreover, the structure of the internal organs of a person, photos and diagrams of which are contained in this publication, is subject to the principles of sexual dimorphism. Their structure is different for men and women, although there are some similarities.
Integumentary system
The internal structure of the human body is a collection of organs that are deeper than the skin. The latter covers the body from the outside and regulates the temperature, protects against external damaging factors of biological, mechanical and chemical nature. The skin completes the holistic anatomical image of the human body.
Scheme of the structure of the body and its functioning
The structure of the internal organs of a person, photos and diagrams of which are contained in the manuals on anatomy, is considered as a collection of cells combined in tissue. The latter form the organs. Moreover, each of them in its own way participates in life. Although more important is the fact that all organ systems are interconnected. For example, the musculoskeletal system is responsible for the movement and maintenance of the posture in space. However, its nutrition is carried out through the vascular system, protection is due to immunological processes, and the muscles are driven by nerve impulses.
Considering the entire structure of man, female internal organs, for example, or male, any researcher will find a lot of relationships. The most important of these is the regulation of respiratory, digestive and circulatory functions through the nervous system. The presence of a respiratory center allows the brain to autonomously regulate respiration and heartbeat.
In addition, endocrine glands affect cardiac function through adrenaline and norepinephrine. And only by this principle is the internal structure of man organized. Photos and diagrams of some organs are attached in the thematic sections of the publication.