disciplines. The importance of anatomy for medicine. Human anatomy (from the Greek anatemno - I cut)- a science that studies the structure and shape of the human body and its constituent organs in connection with their functions and development. It belongs to one of the most important sections of the biological sciences of morphology. The objectives of anatomy as a science are to establish and describe the shape, structure, position of organs and their relationships, taking into account age, gender and individual characteristics. Anatomy also studies the interdependence of the structure, shape of organs and their functions, and reveals the patterns of the design of the body as a whole and its constituent parts.
Anatomy, which is one of the branches of morphology, is connected by a commonality of scientific interests with a number of other sciences, for example, histology, cytology, molecular biology, embryology, comparative anatomy, anthropology, etc.
Human anatomy, together with physiology, forms the theoretical basis of medicine, since knowledge of the structure and function of the human body is necessary to understand the changes caused by disease. In this regard, one of the important areas is applied, or clinical, anatomy, which develops anatomical problems of theoretical and practical medicine. Applied anatomy can be surgical, dental, neurosurgical, etc. Depending on the plan of presentation of human anatomy, systematic, topographic, and plastic anatomy are distinguished. Systematic– describes the structure, shape, position, relationships and development of organs by system. Topographical- provides data on the structure of the body, the position and relationships of organs in areas of the body layer by layer. Plastic– provides information about the statics and dynamics of the external forms of the human body.
2. Methods of anatomical research. Anatomy has a large selection of different methods for studying the structure of the human body. The choice of method depends on the research problem. The oldest method of preparation (dissection) is used to study the external structure and topography of large formations. The injection method is often combined with radiography if the injected mass blocks the X-rays; with clearing, when the object after special processing is made transparent, and the injected vessels or ducts are made contrasting and opaque. Location The organ in relation to other anatomical formations is examined on cuts of the frozen body, called Pirogov sections. Histotopographic method - sections several microns thick processed with histological dyes. Using a series of histological sections and histotopograms, it is possible to reconstruct the studied formation in a drawing or volumetrically; such an action is a graphic or plastic reconstruction. To solve a number of anatomical problems, histological and histochemical methods are used, when the object of study may be discovered at magnifications allowing microscopy. Scanning electron microscopy produces a three-dimensional image of the object under study at low and high magnifications.
3. Basic methodological principles of anatomy: the unity of the organism and the Environment, the integrity of the organism, the unity of structure and function in individual and historical development, etc. Modern science considers the structure of the human body from the standpoint of dialectical materialism. Human anatomy should be studied taking into account the function of each organ and organ system. The features of the shape and structure of the human body cannot be understood without analyzing the functions and structure.
The human body consists of a large number of organs, a huge number of cells, but this is not the sum of individual parts, but a single harmonious living organism. Therefore, organs cannot be considered without interconnection with each other.
The main methods of anatomical research are observation, examination of the body, autopsy, as well as observation and study of an individual organ or group of organs (macroscopic anatomy), their internal structure (microscopic anatomy).
The task of anatomy is to study the structure of the human body using a descriptive method based on systems (systematic approach) and its shape, taking into account the functions of organs (functional approach). In this case, the characteristics characteristic of each specific person - the individual - are taken into account (individual approach). At the same time, anatomy seeks to find out the causes and factors influencing the human body, determining its structure (causal, causal approach). Analyzing the structural features of the human body, examining each organ (analytical approach), anatomy studies the whole organism, approaching it synthetically. Therefore, anatomy is not only an analytical science, but also a synthetic one.
4. The main stages of development of the human body. Critical periods of development. Individual development. The process of intrauterine development of the human body is studied by a special science - embryology, thanks to which it has become possible to reveal the mechanisms of formation of organs and the human body as a whole, to identify ways to improve the structure of living beings. The history of the development of an individual as an individual throughout his life constitutes the concept of ontogenesis (onthos - individual), is divided into two periods: a) intrauterine - continues from the moment of conception and consists of 2 phases: embryonic (the first 2 months) and fetal.
b) postnatal – divided from birth to death of the individual.
At the moment of conception, the male reproductive cell, the sperm, penetrates the female egg, resulting in a fertilized egg, the zygote. It undergoes cell division - crushing, during which from one fertilized egg many small cells are formed - blastomeres, forming a multicellular bastula. The next stage of development - gastrulation - through division and further movement of cells, the separation of the inner germ layer occurs, from which the endoderm develops, the outer germ layer, which goes to the construction of the ectoderm, mesoderm and notochord, vitelline and amniotic vesicles. These vesicles give rise to extraembryonic organs. At the end of gastrulation, the axial complex of primordia can be seen in the embryo.
The next stage of development is the separation of the body of the embryo and the formation of organ rudiments.
The last stage of embryogenesis begins the anatomical formation of organs and the histological differentiation of their constituent tissues. The processes of organogenesis are considered when describing individual organ systems.
The body continues to develop even after the birth of a person: it grows, the structure and shape of organs, their position and relationship changes. The study of the patterns of anatomical changes in the human body after birth relates to age-related anatomy, which is one of the areas of anatomy. There are individual differences in the structure, shape, and position of organs among people of the same age group. This is due to two processes. On the one hand, individual characteristics of the body structure are associated with the fact that the process of intrauterine development proceeds differently in different individuals in relation to both the levels of anlage, the rate of development of organs, and the time of their formation. On the other hand, individual differences in body structure are due to the influence of organ development processes after birth, which depend on the living conditions of a given person.
Embryogenesis is the development of an animal organism that occurs in egg membranes outside the mother's body or inside it from the moment of egg activation or fertilization until hatching or birth.
5. The concept of an organ, organ system, apparatus. The body as an integral system. An organ is an integral formation that has a specific form, structure, function, development and position in the body that is unique to it. An organ system is a collection of homogeneous organs that are similar in their general structure, function and development. The apparatus of organs is a functional combination of heterogeneous organs.
An organism is a living biological integral system with the ability for self-reproduction, self-development and self-government. This is ensured by: the structural connection of all parts of the body; connection of all parts of the body through fluids and the nervous system; the unity of vegetative and animal processes in the body; unity of mental and somatic.
6. Axes and planes in anatomy. Lines and areas conventionally drawn on the surface of the body, their significance for determining the projections of organs onto the skin (examples). Three planes: 1) sagittal (median plane) - a vertical plane through which we mentally dissect the body in the direction of the arrow piercing it from front to back and along the body, thus dividing the body into 2 symmetrical halves - right and left; 2) frontal - vertical plane, at right angles to the sagittal, parallel to the forehead, dividing the body into anterior and posterior sections; 3) horizontal - horizontal, runs at right angles to the sagittal and frontal planes, divides the body into upper and lower sections.
Designation of the position of individual points: medial - that which is located closer to the midline; lateral - that which lies further from the median plane. Proximal is what lies closer to the origin of the limb near the body, distal is what lies further.
For orientation on the surface of the chest, vertical lines are used: anterior midline, sternal line, midclavicular (nipple) line, parasternal line, anterior axillary line, middle and posterior axillary lines, scapular line.
The abdomen is divided into 9 regions using two horizontal and two vertical lines: the epigastrium, hypochondrium, umbilical region and lateral abdominal region (belly), pubic and inguinal regions (hypogastrium). Back areas: vertebral, scapular, subscapular and deltoid.
7. Individual variability of organs. The concept of normal variants in the structure of organs and the body as a whole. Body types. Anomalies. There are 3 body types: 1) dolichomorphic - above average height, relatively short body, small chest circumference, medium or narrow shoulders, long lower limbs, small pelvic angle; 2) brachymorphic - average or below average height, relatively long body, large chest circumference, relatively wide shoulders, short lower limbs, large pelvic tilt angle; 3) mesomorphic – average, intermediate body type.
The norm is a balance achieved due to certain morphological and functional characteristics of the body, and the corresponding body structure is normal. Because Since various factors of the external and internal environment influence the body, the structure of its individual organs and systems varies, but this variability normally does not disturb the established equilibrium with the environment.
An anomaly is a deviation from the norm, expressed to varying degrees, i.e. There are varieties, some are the result of abnormal development and do not affect the functions, others are accompanied by a disorder of the functions of the body or individual organs or lead to its complete inability to live.
8. Brief outline of the history of anatomy. A brief outline of the history of anatomy. Anatomy is one of the oldest sciences. Material monuments of human culture indicate the very early appearance of anatomical information. Scientists Dr. Greece. The ancient Greeks are credited with creating anatomical terminology. Outstanding representatives of Greek medicine and anatomy were Hippocrates, Aristotle and Herophilus.
Hippocrates (460-377 BC)- Ancient Greek physician, reformer of ancient medicine. The works of Hippocrates, which became the basis for the further development of clinical medicine, reflect the idea of the integrity of the body; individual approach to the patient and his treatment; concept of anamnesis; doctrines about etiology, prognosis, temperaments. The main principles of modern medical morality are based on the “Hippocratic Oath” developed in antiquity. He owns a number of works on anatomy and medicine “Hippocratic Collections”.
Aristotle (384-322 BC)- great ancient Greek thinker. He left numerous works: “The History of Animals”, “On the Parts of Animals”, “On the Origin of Animals”, etc.
Herophilus (in 340 BC) – He combined anatomical information and described the unknown to him ventricles of the brain and its membranes, choroid plexuses, venous sinuses of the dura mater of the brain, duodenum, prostate gland, seminal vesicles, etc.
In the Middle Ages, much attention was paid to commentaries on the works of Hippocrates and Galen. During this period, the activity of Ibn Sina, or, as he was called in Europe, Avicenna, the greatest doctor and scientist of the East, stands out.
Abu Ali Ibn Sina (980-1037 AD) scientist, doctor. Lived in Wed. Asia and Iran, was a doctor and vizier under various rulers. His main work is the encyclopedia of theoretical and clinical medicine “Canon of Medical Science” (5 hours) - a generalization of the views and experience of Greek, Roman, Indian and Central Asian doctors - was a mandatory guide for many centuries, including in medieval Europe (approx. . 30 Latin editions).
The 17th century saw several major discoveries in anatomy. In 1628 W. Harvey(1578-1657) described the systemic and pulmonary circulation, as well as its basic laws, laying the foundation for the functional direction in anatomy. G. Azelli described the lymphatic vessels of the intestine, I. Van Horn discovered the thoracic lymphatic duct, M. Malpighi discovered the blood capillaries.
How the human body works from the inside has interested people since ancient times. Even when the basic laws by which people lived were church laws that prohibited studying the structure of the body, there were scientists and naturalists who, in spite of everything, opened the corpses of animals and people and were engaged in examining and studying all the details of interest.
The craving for knowledge in this area could not be overcome. Therefore, over time, it was discovered how the human body works. The diagram, drawing of each organ and system was recorded by artists, testers, doctors, scientists, thanks to this, multiple sciences arose that exist today.
Development of knowledge about the structure of the human body
Back in the 5th century, a man named Alkemon lived in Kraton. It was he who first expressed a desire to study the internal structure of living organisms, so he dissected animal corpses. His main merit is the assumption about the relationship between the senses and the brain.
Later, from about 460 BC, a more conscious and intensive development of knowledge in the area in question begins. The following scientists made a great contribution to the understanding of what the human body is (the diagram of its structure, the topography of the internal organs were also described):
- Hippocrates.
- Aristotle.
- Plato.
- Herophilus.
- Claudius Galen.
- Avicenna.
- Leonardo da Vinci.
- Andreas Vesalius.
- William Harvey.
- Casparo Azelli.
Thanks to these people, a general diagram of the structure of the human body was drawn up. Knowledge appeared about functional features, organ systems, tissues and their significance, as well as other very important things.
The 17th century was a period of stagnation for all sciences, and this did not bypass the area we are considering. But later, the diagram of the human body (you can see the picture below) was significantly expanded, refined and transformed thanks to numerous discoveries. A new technique has emerged that makes it possible to study microstructures, and methods of experiment, observation, and comparison have begun to be intensively used. Special contributions were made by:
Thus, the human body was studied in detail, the diagram became complete and reflected all existing organs and systems. Today, any schoolchild can consider both the topography and a detailed description of each to study the functions performed and the internal structure.
General scheme "Man is a living organism"
If we talk about such a scheme, then it should be noted what exactly it contains. Firstly, it can be presented in different versions. Some such drawings and diagrams contain only verbal descriptions, a classification of the internal structures of a person, reflecting their interconnection and functions performed. Others, on the contrary, do not contain descriptions, but simply illustrate the topographic in the body, show their mutual orientation, the general plan of the structure. Organ systems are also reflected here. If you combine both options, then such a scheme will turn out to be too cumbersome and difficult to understand. The second type is more often used.
Therefore, the “Man is a living organism” diagram includes an image of organs from the following body systems (if a complete version of the whole body is provided):
- Cardiovascular and lymphatic. The diagram of human bodies and channels is reflected here in detail.
- Digestive system.
- Musculoskeletal, or musculoskeletal.
- Reproductive.
- Excretory (genitourinary is the combined system of reproductive and excretory organs).
- Nervous and endocrine systems.
- Sensory, or organs of feeling and perception.
Thus, this diagram provides detailed information about the structure of the human body and the location of its organs. There are also many different tables, figures, diagrams, which reflect the detailed microstructure of any organ. All features of the structure, functioning and location are described.
If you combine all these drawings, you will get a whole book. Such publications are called “Human Biology in Tables and Diagrams” and often make life much easier for schoolchildren, students and teachers. After all, they briefly, succinctly and clearly set out all the basics necessary for a general idea of the structure of people.
Lymph formation system
Immunity plays a special role in maintaining a healthy state of the human body. But what is he? It turns out that this is the lymph circulation system, which is an important addition to the cardiovascular organs. It contains cells called “lymphocytes”. They play the role of a biological protector of the body from viruses and bacteria, foreign particles and everything foreign.
The human lymphatic system, the diagram of which is presented below, has a number of structures that make it up:
- Trunks and ducts.
- Capillaries.
- Vessels.
Together they form a network that is not closed, unlike the cardiovascular network. There is also no central governing body in this system. Lymphatic fluid (lymph) is a waste product of the intercellular space, which moves under weak pressure through vessels and nodes, capillaries, and trunks.
During an illness, such as a cold, every person can feel an increase in the lymph nodes of their body. They are located under the lower jaw, in the armpits, and groin area. It's easy enough to feel them. This confirms the fact that it is in them that the main fight against the disease occurs. Thus, the main barrier to disease is the human lymphatic system. Its diagram shows exactly how all the structural parts are located and how they are interconnected.
Digestive system
One of the most important in the body. After all, it is thanks to her work that a person receives nutrients for growth, development, and energy for vital processes. Without it it is impossible to move, grow, think, and so on. After all, every process requires energy, which is contained in the chemical bonds of nutritional molecules.
A diagram of the human digestive system shows which organs make up this network.
- The oral cavity, which includes the teeth, tongue, palate and inner muscles of the cheeks.
- Pharynx and esophagus.
- Stomach.
- secretes secretions for digesting food.
- The intestine consists of several sections: duodenum, small and large intestines.
The cardiovascular system
It represents two circles of blood circulation, consisting of the main organ - the heart - and the arteries, vessels, and capillaries extending from it. The total blood volume of an adult is approximately 5 liters. However, the rate varies depending on body weight.
The heart is a central organ capable of contracting rhythmically, pushing blood into the channel under a certain pressure. Consists of four chambers closely communicating with each other.
Human nervous system
One of the most difficult. Comprises:
- brain;
- spinal cord;
- nerve cells;
- fabrics.
Almost every part of the human body contains nerve cells. They perceive irritation, transmit pain, warning of danger. Their structure is quite unique. The brain and spinal cord include a number of sections, each of which exercises careful control over the functioning of a particular part of the body.
Sensory systems
There are five of them:
All of them together also make up the human body. The structure diagram shows what parts the sensory system is made up of, what structural features it has and what functions it performs.
Human excretory system
This system includes the following bodies:
- kidneys;
- bladder;
- ureters.
Another name for this system is excretory. The main function is the removal of metabolic products, liberation of the body from toxic decay products.
Sciences that study the human body
There are several main ones that can be identified. Although their number has increased significantly compared, for example, with the 18th century. These are sciences such as:
- anatomy;
- physiology;
- hygiene;
- genetics;
- medicine;
- psychology.
Physiology deals with the functioning of a particular system. That is, its task is to answer the question: “How does this happen?” For example, it is this discipline that examines the mechanisms of the change between sleep and wakefulness, and studies the features of higher nervous activity in humans.
Genetics and human hygiene
Genetics deals with the study of the mechanisms of inheritance of certain traits, as well as the causes and consequences of changes in the human chromosomal apparatus. Thanks to this science, people have learned to predict serious genetic abnormalities in fetal development, control this process and, if possible, intervene and change its course.
Hygiene helps answer the question: “Why do we need cleanliness and how to achieve health?” This science talks in detail about the rules for maintaining the cleanliness of your body, the importance of this process, and the mechanisms of immunity, which directly depend on the indicator of cleanliness, the level of bacteria and viruses. This discipline is relatively young, but no less important than all the others.
Psychology and medicine
Psychology is a very complex and subtle science that penetrates into the consciousness and higher nervous activity of a human being. It is intended to explain the basic mechanisms of the psychosomatic structure of people. There are a number of branches of psychology that deal with all social issues affecting people (psychology of family relationships, developmental, experimental, and so on).
Medicine is the most important science that deals with human health. Naturally, it closely borders on all other disciplines: physiology, anatomy, genetics, hygiene and psychology.
The foundations of medicine originated with humanity. After all, unfortunately, people have always gotten sick. At all times, hereditary (genetic) diseases and other ailments accompanied them. Therefore, this science is one of the most important when it comes to preserving life and health.
There are many sections that combine medicine into a single whole: surgery, oncology, hematology, therapy, dermatology, traumatology and others. All of them are highly specialized in specific problems and have their own methods of studying the problem and resolving it.
In general, all sciences that study the human body are a single whole. After all, they are united by a common goal - to study, examine, explain all parts of the body, learn to control every organ and every cell of the body.
Anatomy as the main science
Of course, the very first, historically established and its structure is anatomy. It was thanks to the development of this discipline that people became aware of what organs are in the human body, how they are located there (topography), how they are structured and on what principles their work is based.
Above we examined the main historical milestones in the development of knowledge about man. These are the stages of anatomy development. Those people whose names were mentioned are the founders and fathers of this huge and important discipline.
The task of anatomy has always been the same for all times - to study the internal structure and external morphological characteristics of all organs and systems, as well as tissues. It’s not for nothing that “anatome” is translated from Greek as “dissection”.
The most important of them:
1) The law of historical development is that all living organisms, regardless of their level of organization and habitat, have gone through a long path of historical development ( phylogenesis);
2) The law of unity of both the organism and the environment. Sechenov. It says that an organism without an external environment that supports its existence is impossible.
3) The law of integrity and indivisibility states that each organism is a single whole and indivisible, in which all its parts are in close genetic, morphological, functional relationship and interdependence;
4) The law of unity of form and function. Each organ in the body has several functions, of which, in the course of historical transformations, only one acquires predominant importance, while others disappear. With all these transformations, the structure of the organ and its functional functions are equally involved, i.e. form and function form an inextricable whole.
5) The law of homologous series concludes that the closer the genetic species are, the more accurately and sharply the similarity of the series of morphological and physiological characteristics is manifested. It is the basis of comparative anatomy.
6) The law of saving space and material. All organs and systems in the body are built in such a way that with minimal expenditure of “building material” they are able to perform maximum work.
7) The law of heredity and variability.
8) Basic biogenetic law. Anatomy studies the body throughout life, i.e. from fertilization to death (ontogenesis). Ontogenesis– individual development of the body. 2 stages: 1) prenatal (from the moment of fertilization to birth); 2) postnatal (after birth until death). The prenatal period has 3 periods: embryonic, prefetal and fetal. Postnatal includes 6 periods: neonatal, milk, juvenile (age), period of puberty, period of morphofunctional maturity and gerantological period.
Basic laws (principles) of the structure of the body:
1) Bipolarity(uniaxiality) - the presence of two opposite poles of the body (head - cranial direction; tail - caudal direction);
2) Segmentation(metamerism) - the body is divided into separate metameres (sections = segments), which are repeated one after another along the longitudinal axis. This makes it easier to study the skeleton or any system.
3) Antimeria(bilateral symmetry = bilateral) – mirror similarity of the right and left halves of the body, i.e. The animal's body is divided along the longitudinal axis by the median plane (planum medianum). The organs located on either side of this plane are called antimers(kidneys, lungs). Not only organs, also limbs, temporal bones, maxillary bones, etc. Unpaired organs and bones usually lie in the median plane and are divided into 2 identical halves. Example: occipital bone, tongue, spinal cord, brain, all vertebrae.
4) Law of tube-shaped construction. All systems and apparatuses of animals develop in the form of a tube (nervous, digestive, excretory). The result of reflecting the law of saving space and material.
Osteology- science of bones. General characteristics of the movement apparatus. Skeletal system. The structure of bones and their classification.
Movement apparatus includes a skeletal (passive) part and a muscular (active) part. Both parts of the movement apparatus have a common origin from the middle germ layer (mesoderm) and are closely interconnected and interdependent.
Skeletal system(animal skeleton), the functions of which are as follows:
1) Mechanical function:
a. They are a strong skeleton of the body, providing reliable protection and normal functioning of all organs (spinal cord, brain, lungs, heart);
b. The skeleton is a system of levers that provides dynamics and statics;
2) Biological function.
a. In the bones there is a depot of mineralization (calcium, phosphorus).
b. Serves as a receptacle for bone marrow (hematopoietic function)
Each skeleton has its own distinctive features. From individual bones we can tell about age, mineralization, etc.
The number of bones varies from 200 to 280.
Bone mass in relation to body mass 7-15%. On the skeleton of the limbs - 50%, torso – 30% , head - 20%. 1/3 – skeleton of the thoracic limb, 2/3 – thoracic limb.
Chemical composition and physical properties of bones. Fresh bones contain 50% water, 15% fat, 12% organic matter, 23% inorganic matter. sternum – 30% fat. Young bones are soft and elastic, because contain more organic substances (ossein, which provides bones with flexibility and elasticity). In old age, there are more minerals, bones become less elastic and more fragile.
The structure of bone as an organ. Vascularization (blood supply). The outside of the bone is covered with periosteum ( periosteum), has 2 layers: 1) surface(fibrous layer), consists of dense connective tissue and is rich in blood vessels and nerves, so the bone in the body has a faint pink color and is very sensitive. This layer is especially developed where ligaments and tendons are attached. 2) interior(cambial) layer. It has a more delicate structure, is poor in blood vessels, but has many osteoblasts, due to which young bones grow in width, and in an adult body, restoration of defects and fusion after fractures occurs.
Under the periosteum there is a compact substance.
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The compact substance that covers the bone, a unit - osteon - is a system of light tubes inserted into each other and fastened together, located along the compressive force experienced under loads. This layer is most pronounced in diaphases and becomes thinner towards epiphases.
Spongy substance(substantia spongiosa) from membranous bone plates? Containing small cells and filled with bone marrow.
Bone marrow(medulla osteon) – red and yellow. Red bone marrow in the spongy substance of the vertebral bodies, ribs, sternum and epiphyses of long tubular bones, in the bones of the base of the skull. Yellow bone marrow in the diaphysis of long tubular bones consists of adipose tissue with hematopoietic particles.
Each bone is equipped with blood vessels that enter from the periosteum through the nutrient openings (foramen nitricum).
Classification of bones:
1) By origin:
a. Primary (2 stages of development: connective tissue, bone) (covering bones of the skull - incisive, maxillary, nasal, frontal, parietal, interparietal). Clavicle, lower jaw.
b. Secondary (3 stages: connective tissue, cartilage, bone). Most of the bones.
2) In form:
a. Long (os longum)
i. Arc-shaped (rib);
ii. Tubular (length > width and thickness). They are called so because a cavity for the bone marrow is formed in the middle part of the diaphysis; performs the function of leverage and protection.
b. Short (os breve) length = width. The bones of the wrist and tarsus (so, where great mobility is combined with a large load, perform depreciation). Sisamoid bones (patella)
c. Flat (os planum) form the walls of the cavities and girdles of the limbs. Protective function. They have spacious surfaces for muscle attachment (pelvis, scapula, skull cap);
d. Mixed (os irregulare). Vertebrae, sphenoid bone.
e. Air bones (os pneumaticum). They have a sinus in the body filled with air (maxillary, frontal and sphenoid sinuses). May communicate with the nasal cavity.
3) According to topography. The bones of the neck, head, torso, and tail are united into the axial skeleton. The bones of the limbs are the peripheral skeleton.
Phylo- and ontogeny of the skeleton. The internal skeleton has the most primitive structure in coelenterates, in which it is represented by acellular connective tissue membranes. In arthropods, the chitinous skeleton, which performs a protective function and serves for muscle attachment, is of particular importance. In roundworms the skeleton is represented by a system of plates, cords or membranes. In cephalopods In molluscs, the connective tissue skeleton in the area of the head, back, and base of the fins is replaced by denser structures resembling cartilage. At the lancelet only the notochord has a more elastic structure, and the rest of the skeleton is represented by fibrous connective tissue, which is the predecessor to all other tissues involved in the formation of the internal skeleton of vertebrates.
Conversion of a membranous skeleton to a cartilaginous one (cartilaginous fish), then into inert (bony fish, amphibians, birds and mammals) is due to the fact that animals adapt to more complex living conditions.
During ontogenesis bones go through 3 stages of their development and formation. In the early stages of embryonic development, a connective tissue or membranous framework, represented by membranous bones, is formed from the mesoderm. Subsequent changes are characterized by the gradual replacement of the connective tissue base with cartilaginous tissue with the formation of cartilaginous bone. At the third stage, cartilage tissue is replaced by bone tissue, which can occur in two ways: either from the inside of the cartilaginous bone (endochondral type of ossification) or from its surface (perichondral ossification).
Limb skeleton represented by two pairs of limbs (ossa membri thoracia et pelvini). They include the girdle of the thoracic limb and the girdle of the pelvic limb (cingulum...) and the skeleton of the free section.
Shoulder girdle represented by the scapula (os scapula) and weakly defined coracoid and clavicle. The shoulder blade is flat, almost triangular in shape. Lies obliquely on the side of the chest. It connects ventrally with the shoulder, forming the shoulder joint. This is its narrowest part. This is approximately 1-2 ribs. Dorsal to the withers, the scapula widens. All this and its oblique position allows it to perceive strong shocks from the pelvic limbs during rapid movements. The body rests on the scapula mainly in the area of attachment of the ventral serratus muscle (serratus). The spine of the scapula ends with the acromion (dog and cattle) and does not have it in the horse and pig. The degree of its development depends on the need for greater or lesser abduction of the limbs to the side (abduction). The freer it is, the more strongly the acromion is expressed by the corresponding muscles. On the dorsal edge there is cartilage, which is most pronounced in ungulates, and in pigs and dogs in the form of a strip.
Clavicle (clavicula) sometimes preserved in the form of a plate in the distal third of the neck.
Coracoid in the form of a small process is located on the supraglenoid tubercle of the scapula on the medial side. Most pronounced in horses.
The free section is represented by the humerus and is called this section (stylopodium - one ray).
Bones of the forearm (ulna and radius). The department is called zeygopodium - two rays.
Brush– autopodium.
On the pelvic limb, the pelvic girdle is represented by the paired pelvic bone (2 os coxae = os pelvis). Ventrally, both innominate (pelvic) bones are connected by a symphysis, which at a young age is represented by cartilaginous tissue and then ossifies. The pelvis is formed by the fusion of the ilium, ischium and pubic bones. At the site of fusion, the acetabulum is visible, which with the head of the femur forms the hip joint and a locked opening for blood vessels, nerves and muscles. The pelvic bones, connecting ventrally with each other, and dorsally with the sacrum, form the pelvic cavity (cavum pelvis). It has a cone-shaped cavity with the apex directed caudally, except in dogs (in them it expands caudally). The lateral walls of the pelvis are formed by the ilium and ischium. The roof (arch) of the pelvis is represented by the sacrum and the first caudal vertebrae. The bottom (base of the pelvis) is represented by the pubic and ischial bones.
Free section of the pelvic limb. Zeigopodium – tibia (fibula and tibia), stylopodium – thigh. Autopodium – foot.
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Phylogeny of limbs
In chordates, the initial form is a muscular lateral fold in the aquatic environment, which is subsequently reduced into paired pectoral and ventral fins.
In cartilaginous fish, the fins are located in a horizontal plane, their size increases, the cartilaginous base is strengthened, which are then transformed into the skeleton of the limb girdles. Gradually, the fins are directed at an angle, and the cartilage is replaced with inert tissue.
In amphibians, due to adaptation to a terrestrial lifestyle, the fins turn into legs and are divided into belts and free limbs. The main movements are lateral bends of the body and tail. The shoulder girdle is further divided into a dorsal section (scapula) and a ventral section (coracoid and clavicle), with the coracoid being more developed. The pelvic girdle has the most developed ventral section (ischium and lunar bone), while the dorsal section is poorly developed.
Subsequently, differentiation of the limbs became possible due to the rotation of the limbs from the transverse plane to the lateral plane, lifting the body from the ground and bringing them under the body. These transformations lead to greater development of the dorsal parts of the girdles and the transformation of the limbs into active organs of movement. In the pectoral limbs, due to the development of the scapula, the coracoid and clavicle are reduced.
Skull (cranium)
2 sections: head (carebrale) and facial (viscerale)
The border between the facial and brain regions is a transverse plane drawn through the orbit. It is formed by 6 unpaired and 13 paired bones. At a young age, the bones are connected by fibrous connective tissue in the form of sutures, which gradually ossify. The ratio of the departments depends on the development of the teeth and the development of the brain.
Functions of the skull:
1) The skull contains the brain and protects it, forming the cranium with the cranial cavity. The head contains sensory organs that are protected by a bone base:
a. Bone orbit (for the eyes). In large ones, the orbit is closed (lacrimal, zygomatic, frontal, temporal). In small animals the orbit is not closed;
b. Labyrinth of the ethmoid bone. Contains an olfactory analyzer;
c. Petrous bone. The auricle is attached. The skeleton of the equilibrium-auditory analyzer;
2) The respiratory tube and the digestive tube begin on the head. The spinal cord enters the brain through the foramen magnum.
General characteristics of the facial part of the skull. It includes bones that serve as the skeleton of the nasal and oropharyngeal cavities. From the surface of the facial skull, the bone bases of various areas are distinguished:
1) The bone base of the nasal region (region nasalis), is located dorsally and is a continuation of the bone base forward of the frontal region;
2) Bone base of the incisive region (incisive bone);
3) Bone base of the buccal region (main maxillary bone);
4) Bone base of the masticatory muscle (mandibular bone);
5) Bone base of the palatal region (incisive bone, maxillary and palatine). Behind it opens the entrance to the pharynx and bone base of the joanal region.
The facial section is located in front from below in relation to the brain section and there are 2 sections distinguished in it: the lower, longer one is the skeleton of the oropharyngeal cavity and the upper, shorter one is the skeleton of the nasal cavity. The border between them is the bony, hard palate, which is the bottom for the nasal cavity, and the roof for the oral cavity. Both sections converge towards the incisal region into a blunt apex. This is especially clearly visible in pigs, which is supplemented by a proboscis bone (piglet).
General characteristics of the cranial cavity (cavum cranium). It is divided into 2 unevenly developed sections: the rhombencephalon (small brain), smaller in volume, contains the medulla oblongata and hindbrain; the cerebrum serves as a container for the midbrain, diencephalon and telencephalon. The boundary of the departments is the hanging tentorium (tentorium osseum) of the interparietal bone. At the bottom of the cranial cavity, the boundary is the muscular tubercle, between the bodies of the occipital and sphenoid bones. In both of these departments there are 2 departments:
1) The upper wall (= fornix = roof = cranial cover = calvaria), which is formed from back to front by the squama of the occipital bone, parietal, interparietal bones, frontal and part of the squama of the temporal bone; The lacrimal and zygomatic lie on the border of the brain and facial sections. A characteristic feature of the roof of the skull is that on the entire surface on the side of the brain there are digital impressions (impressionis digitalis) - they are imprints of the convolutions of the cerebral hemispheres and cerebellum.
2) The bottom of the brain, which includes the body of the occipital and sphenoid bones. What is characteristic of these bones is that they can be classified as mixed unpaired bones.
Species features of the skull as a whole:
Horse. The skull is relatively more or less light with a very developed facial part and a heavy lower jaw, which is associated with the nutrition of the animal. The nasal bone and nasal cavity are well developed, the maxillary sinuses (maxillary sinuses), the zygomatic ridge, the brain region is small, streamlined in shape, the temporal fossa is well developed, the orbit is closed, large ragged foramina, because the tympanic bladder is poorly developed. The petrous bone is independent.
Cattle. The skull is heavy, massive, angular. The cranial cover is extensive and smooth, with powerful horny processes on the sides. The interparietal bone is displaced back to the occipital region. The torn holes are slit-like. The upper jaw does not bear incisor teeth. The lower jaw is poorly developed.
Pig. The skull is massive, wedge-shaped and, as it were, “attached” for digging with the snout (snub). It has a strongly expanded and concave posterior occipital region. The cranial cover and the facial part are concave on top. The brain region is small, the orbit is not closed.
Dog. The skull is light, with a developed brain part, the orbit is not closed and the lacrimal bone is small. Round head, short and wide - brachycephalic; oblong head, long and narrow - dolichocephals; intermediate form - mesatocephals.
Arthrology (syndesmology) – the doctrine of the connection of bones.
Types of bone connections
Continuous and discontinuous connections.
Continuous connections (fusions) are the most ancient in origin, and are mainly found where significant strength and limited mobility are required to ensure organ protection, joint elasticity, elasticity and flexibility.
Types of continuous connections:
Fibrous connections. The presence of dense connective tissue between connecting bones:
1) Syndesmosis - connection of bones through dense connective tissue ( simple syndesmosis, when the connection of bones due to collagen connective tissue: interosseous ligaments and membranes; elastic, using elastic connective tissue: yellow ligaments);
2) Through sutures (sutura). Characterized by one or another shape of the edges of the bones in contact: flat (smooth = sutura plana: nasal bone); scaly (sutura squamosa: parietal from the temporal bone); serrated (sutura serrata: nasal bones with frontal bones); leaflet (sutura foliata, a type of dentate, but individual teeth are more deeply embedded: the wings of the sphenoid bone with the frontal and parietal bones); split suture (sutura schindylesis, the sharp edge of one bone is wedged into the split edge of another: the nasal process of the incisive bone with the maxillary bone).
3) Gomphosis – teeth in the sockets on the maxillary, mandibular and incisive bones.
Cartilaginous connections characterized by the presence of cartilaginous layers between the bones:
1) Synchrondrosis - hyaline cartilage between the bones (rib cartilages, articular surfaces of the entire bones), with age it is replaced by bone tissue;
2) Symphysis - fibrous cartilage between the bones (pelvic bones, intervertebral discs).
Muscle junctions (synsarcosis) between the bones there is muscle tissue (scapula with torso).
Bone connection (synostosis) replacement of cartilage or dense connective tissue with bone.
Discontinuous connections (joint) through the joints. Occurs where significant mobility is needed. Each joint must contain: articular surfaces, articular capsule, articular cavity, articular (synovial) fluid filling the joint cavity.
The joint may include various inclusions: discs, menisci, which strengthen the joint and provide congruence (alignment) and provide strictly defined functions.
Articular surfaces (facies articularis) covered with articular (hyaline) cartilage, thickness from 0.2 to 0.5 cm, which ensures alignment. Mostly hyaline cartilage is found, sometimes it can be fibrous. It also provides sliding and reduced friction (very elastic).
Articular capsule (capsula articularis) being fixed along the edges of the articular cartilages, it forms a hermetically sealed cavity. It consists of 2 layers: the outer layer (fibrous), which performs a protective function, and the synovial layer, which produces a viscous fluid (synovium), which facilitates the sliding of articular surfaces, serves as a nutrient medium for articular cartilage, and metabolic products of cartilage tissue are released into it.
The English scientist D. Wald wrote that “... the most complex machine that man has ever created - well, let’s say, the “electronic brain” - is nothing more than a child’s toy compared to the simplest living creature.”
Man, as we know, is the most complex of living beings. To understand the structure and operation of any machine, you need to have a diagram of its design. To understand how the human body works and how it functions, you must first get acquainted with the general plan of its structure.
A well-known analogy can be drawn between a machine and a living organism: in both cases, energy is needed to ensure operation, and in both cases, aging parts need to be replaced. So, for example, a person who is in a state of complete rest, to ensure his vital functions - breathing, heart contractions, tone, etc. - requires 1700 kcal per day *; during work, the energy requirement increases to 3000 and even 7000 kcal (at high physical exertion).
The work of organs is accompanied by their continuous renewal: some cells die, others replace them. This process occurs unnoticed by us, but in reality the extent of such natural tissue loss and restoration is quite significant. For example, in an adult, approximately 1/20 of the skin epithelial cells die and are replaced within 24 hours, 1/2 of all epithelial cells lining the mucous membrane of the digestive tract are replaced by about 25 g of blood, etc.
In the body of animals and humans, the formation of energy and the replacement of aging and dying tissues occurs due to metabolism. A large group of organs carries out this basic life process. This includes, firstly, organs that ensure the intake of chemicals from solid and liquid food into the body; secondly, the organs of the respiratory system that deliver oxygen from the air. In the tissues of the body, some chemical substances combine with oxygen (“burn”) and serve to generate energy, while others are used as “building material” for cells and other tissue structures. Of course, in the process of complex chemical transformations occurring in the digestive canal, in the cells and tissues of various organs, many by-products that are unnecessary for the body are formed, which often have a toxic effect - they must be removed, and for this there are special excretory organs (kidneys, sweat glands and etc.). Finally, living organisms have the ability to reproduce themselves - without this, life, of course, would cease, therefore, in addition to those mentioned, there are also reproductive organs.
If we compare animals and plants, it is easy to see that in the latter case there are also organs of nutrition, respiration, excretion and reproduction. But this is where their “economy” is limited. And this is understandable. Plants feed on inorganic substances: carbon dioxide from the air, water and mineral salts of the soil. From these inorganic substances they form, using solar energy, organic substances: proteins, fats, carbohydrates, from which their body is built. They do not need to search for food and live in one place. The situation is different with animals. Unlike plants, they cannot create organic substances from inorganic ones in their bodies; they must receive them in finished form from the bodies of other living beings. In this regard, animals, as a rule, spend their lives in search of food. Its extraction requires movement, therefore, in animals, during the history of their development, organs of movement are formed, which plants do not have. That is why the organs of the digestive, respiratory, excretory system and reproductive organs are usually called organs of plant, or vegetative, life, and the apparatus of movement, nervous system and sensory organs, which are closely interconnected in the process of evolutionary development, are called organs of animal, or animal, life. Strong bones and their flexible joints, covered with strong muscles and covered with skin, make up the body, head and mobile limbs of a healthy body. The "internal mechanism" of the body is contained in its cavities. Let's fit it into the familiar contours of the human torso (Fig. 5).
Rice. 5. General view of the location of the internals.
1 - larynx;
2 - trachea;
3 - lungs;
4 - heart;
5 - stomach;
6 - liver;
7 - small intestine;
8-11 - large intestine;
12 - bladder.
* Kilocalorie - the amount of energy required to heat 1 kg of water by 1°C. The energy that is necessary to ensure the functioning of the body at rest is called basal metabolism. It represents an important characteristic of body functions.
Description of presentation Lecture General principles of the structure of the human body. Cells and slides
Lecture General principles of the structure of the human body. Cells and tissues Plan: 1. Principles of the structure of the human body. 2. Cells. 3. Fabrics.
Anatomy from Greek. "anatome" - dissection, dismemberment. Anatomy is the science of the forms, structure, origin and development of the human body, its systems and organs. Anatomy examines the structure of the human body and its organs at different periods of life, from the intrauterine period of life to old age, and examines the characteristics of the body under the influence of the external environment. Anatomy includes sections: 1. topographic anatomy; 2. systematic anatomy; 3. Functional anatomy
Anatomy terms Symmetrical organs are a mirror image of each other. For example: right and left hand, etc. Asymmetrical organs - spleen on the left, liver on the right of the midline. Anatomical position: Vertical body position, upper limbs brought to the body, palms facing forward, neck straight, gaze directed into the distance.
The location of body parts and their constituent organs is described using imaginary lines or planes.
To indicate the location of organs in relation to: - The terms are used to the horizontal plane: Cranial (from Lat. Cranium - skull) (upper) Caudal (from Lat. - tail) (lower). — Frontal plane: — Ventral (lat. Ventral-stomach) (anterior) — Dorsal (lat. Dorsal-back) (posterior) — Lateral-lateral (farther from the middle) — Middle-medial (closer to the middle). — To designate parts of the limbs, the terms are: proximal (closer to the body), distal (farther from the body).
Levels of organization of a person as a living being: Molecular Cellular Tissue Organ Systemic Organism Organ - a part of the body that has its own unique shape, structure and occupies a certain place in the body and performs characteristic functions (muscle, liver, eye, etc.). An organ system is organs that have a common structural plan, a common origin and perform a single function. Organ apparatuses are organs that have different structures and origins, but are connected by performing a single function. The body is the systems and apparatus of organs that work as a single whole.
Organ systems: Bone Muscular Nervous Digestive Respiratory Cardiovascular Urinary Immune Genital Skin Apparatuses: Musculoskeletal Genitourinary Endocrine
A cell is the elementary unit of living things. Properties of living things: -metabolism; -heredity; -variability; -reproduction; -development and growth; -movement; -irritability; -adaptation. A CELL consists of cytoplasm and nucleus. Cytoplasm consists of hyaloplasm (cytosol) and organelles (organelles). Cells are divided into somatic and reproductive cells. The sizes and shapes of cells are varied.
The nucleus consists of chromatin, nucleolus, karyoplasm, nuclear membrane. Core functions: storage and transmission of genetic information; implementation of genetic information (protein synthesis, regulation of cell activity) Chromatin - a complex of DNA and proteins (histones and non-histones) Chromatin Euchromatin (weakly condensed, active) Heterochromatin (strongly condensed, inactive) Facultative (contains genes that are not active in a given cell at a given time ) Constitutive (structural) does not contain a gene nucleus nucleolus euchromatin heterochromatin
Cytoplasmic membrane The membrane is a mobile fluid structure consisting of a bilipid layer (phospholipids) and protein molecules immersed in it. On the outer surface there is a glycocalyx (glycolipids, glycoproteins) Functions: Barrier protective Transport Receptor Secretory Formation of intercellular contacts Participates in cell movement
The endoplasmic reticulum is a system of channels and cavities. Two types: 1. rough (granular) contains ribosomes 2. Smooth (agranular) no ribosomes. Functions: Protein synthesis Synthesis and accumulation of carbohydrates and fats Spatial separation of cell enzyme systems
Golgi apparatus. A network of membrane cavities (5-8), from which tubes and vesicles extend. Functions: 1. Accumulation and chemical modification of substances that are synthesized in the ER 2. Transport of substances from the cell 3. Formation of lysosomes
Mitochondria This is a double-membrane organelle: the outer membrane is smooth, the inner one forms folds. Inside is a matrix containing liquid, circular DNA, RNA, ribosomes Function: ATP synthesis
Ribosomes consist of two subunits: small and large. Chemical composition: RNA and proteins. Ribosomes are located freely in the cytoplasm and on the ER membrane, the nuclear envelope. Function: protein synthesis.
The cell center consists of two centrioles (mother and daughter) and a centrosphere. Consist of microtubules. Formula: (9 x3)+0 Functions: formation of the spindle, lie at the base of cilia and flagella.
Cilia, flagellum Cell outgrowths surrounded by a membrane are capable of movement. They consist of a protein called tubulin. Intra-axoneme (9 x2)+2 Function: provide movement.
Tissues are a group of cells and extracellular substances that have a common origin, structure and function. Types of tissues: Epithelial Connective Muscular Nervous
Epithelial tissues cover the surfaces of the body, line the mucous membranes of internal organs, and form most glands. Functions: barrier, protective, excretory, absorption. They are divided into integumentary and glandular. General structural features: 1. Epithelia consist of epithelial cells that form layers lying on the basement membrane 2. There is no intercellular substance between the cells; they are connected using special contacts. 3. There are no blood or lymphatic vessels, nutrition is carried out through the basement membrane by diffusion from the connective tissue. 4. They have the ability to quickly recover through mitosis. Covering epithelium is divided into single-layer and multilayer. Single-layer: cubic, prismatic, flat, etc. Multilayer: squamous keratinizing epithelium, squamous non-keratinizing epithelium, transitional epithelium.
Connective tissues are divided into: 1. Connective tissues proper: - Loose connective tissue; — Dense connective tissue 2. Connective tissues with special properties: fatty, pigmented, reticular, mucous. 3. Blood and lymph 3. Skeletal tissues - cartilage and bone
Blood and lymph Blood is red tissue, consisting of plasma (55%) and formed elements (45%). Formed elements: Red blood cells Leukocytes (neutrophils, basophils, eosinophils, lymphocytes, monocytes) Platelets Blood functions: Respiratory Nutritional Protective Regulatory Homeostatic Immune. Lymph is a clear yellowish liquid. Consists of lymphoplasm and lymphocytes. Function: trophic, immune.
Loose connective tissue. This tissue forms membranes around organs, accompanies blood vessels, and fills the space between organ cells. The main function is to create conditions for the life of organ cells (trophic, respiratory, immune, regulatory and other functions). Loose connective tissue consists of cells and intercellular substance. PCT cells: fibroblasts, fibrocytes, macrophages, mast cells, lymphocytes, fat cells, adventitial cells. The intercellular substance consists of a ground (amorphous) substance and fibers (collagen, elastic, reticular). Fibers form three-dimensional networks and create a tissue frame; cells and substances move through them.
Dense connective tissue consists of cells (fibrocytes) and intercellular substance (many fibers, little amorphous substance). There are 2 types: formed (tendons, ligaments, capsules, etc.) and unformed (dermis of the skin).
Bone tissue: reticulofibrous, lamellar. Bone tissue consists of cells (osteogenic, osteoblasts, osteocytes, osteoclasts) and intercellular substance (ossein and minerals (calcium phosphates)
