Anatomy

What bones belong to the axial skeleton

LESSON №11, 12 "Human Skeleton"

Tasks:

1. Replenish knowledge about the structure and functions of the parts of the skeleton, compare it with the skeleton of mammals, identify the features of the human skeleton associated with upright posture, brain development, and labor activity.

2. Introduce students to the types of bone connections.

I. Check of knowledge.

1. Reveal the role of the skeleton.

2. Talk about the types of bones.

3. Describe the experiments that reveal the role of organic and mineral matter in ensuring bone strength.

4. Tell about the growth of bones in width and length.

II. new material

Skeleton- a set of hard tissues in the body that serve as a support for the body or its individual parts and protect it from mechanical damage.

Axial skeleton- unites the skull and skeleton of the body.

Additional skeleton- consists of the bones of the limb belts and the skeleton of the free limbs.

The mass of the skeleton is 11 kg. The skeleton contains about 200 bones (86 paired)

Head skeleton:

    parietal (2), temporal (2), frontal (1), occipital (1), zygomatic (2), nasal (2), lacrimal (2), lower jaw (1), upper jaws(2), sphenoid (1), hyoid (1) bones + auditory ossicles (6)

The skull is made up of 23 bones. Only 2 are mobile (mandible and hyoid bone)

Body skeleton:

    spine = 33-34 vertebrae

departments: cervical (7)

chest (12)

lumbar (7)

sacrum (5)

coccyx (3-4)

vertebra = body + 1 transverse process + 2 spinous processes

    chest = 12 pairs of ribs + sternum

Upper limb skeleton (30 bones)

    shoulder girdle = collarbones + shoulder blades

    upper limb = shoulder ( brachial bone– 1) + forearm ( elbow bone+ radius) + bones of the wrist (8) + bones of the metacarpus (5) + bones of the phalanges of the fingers (14)

Skeleton lower extremities(30 bones)

    lower limb belt (pelvis) = pelvic bones(iliac (2) + ischial (2) + pubic (2))

    lower limb \u003d femur (femur - 1) + patella (1) + lower leg (tibia + fibula) + metatarsal bones (7) + tarsal bones (5) + bones of the phalanges of the fingers (14)

Types of bone connection

Due to the flattening of the intervertebral cartilage, growth decreases by 1.5 cm in the evening, and by 5-7 cm by the age of 80.

Joint structure:

Articular bag

joint fluid

articular head

articular cavity

skeletal features, related to bipedalism and labor:

lumbar

chest

sacral

    The chest is expanded to the sides

    Contrasting the thumb

    Wide belt of lower extremities, pelvis in the form of a bowl

    The bones of the lower extremities are stronger than those of the upper ones.

    Arched foot

    The brain skull prevails over the facial

III. Anchoring

    Which parts of the skeleton belong to the axial skeleton, and which parts to the accessory?

    How is the skull attached to the spine? Why should a newborn's head be held?

    Questions in the workbook 35-42 (p).

IV.D / s paragraph 11, 12

The musculoskeletal system includes the skeleton and muscles, combined into a single musculoskeletal system. The functional significance of this system lies in its very name. The skeleton and muscles are the supporting structures of the body, limiting the cavities in which internal organs. With the help of the musculoskeletal system, one of the most important functions of the body is carried out - movement. Movement is the main external manifestation of the activity of the organism and, at the same time, a necessary factor in its development. In conditions of restriction of movements, both physical and mental development. It is shown that if newborn animals are deprived of the possibility of free movement, then already in the first month their weight becomes 3 times less than that of individuals of the same litter. Motor activity, especially hand movements, is one of the necessary conditions for the normal development of the brain, its speech function and thinking. Physical activity also plays essential role in metabolic processes, positively affects the work of all internal organs.

Knowledge age features organs of movement and conditions conducive to their normal development, it is necessary to develop effective means and methods of physical education, labor training, organization of the daily routine.

The skeleton is the structural basis of the body. The skeleton forms the structural basis of the body and largely determines its shape and size (Fig. 28). The skeleton consists of bones, in an adult there are more than 200 of them. The role of the bones is not limited to the function of support. The mineral salts that make up their tissues are one of the most important elements metabolic processes. In the bones there is also one of the main organs of hematopoiesis - the bone marrow.

Each bone is a complex organ consisting of bone tissue, periosteum, bone marrow, blood and lymph vessels and nerves.

The bone, with the exception of the connecting surfaces, is covered with periosteum. This is a thin connective tissue sheath, which is rich in nerves and blood vessels that penetrate from it into the bone through special openings. Ligaments and muscles are attached to the periosteum. The inner layer of the periosteum consists of cells that grow and multiply, ensuring the growth of the bone in thickness, and in case of fractures, the formation of callus.

The structure of bones provides their main property - mechanical strength. The properties of the bone are also provided by their chemical composition. Bones contain 60% minerals, 30% organic, 10% water.

The mineral substances of the bone are represented by salts of calcium, phosphorus, magnesium; many trace elements have been found (aluminum, fluorine, manganese, lead, strontium, uranium, cobalt, iron, etc.). In an adult, about 1200 g of calcium, 530 g of phosphorus, 11 g of magnesium are concentrated in the skeleton; 99% of the calcium in the human body is found in the bones. Among organic substances - fibrous protein - collagen, carbohydrates, enzymes. Minerals, especially calcium, make bones hard, organic substances give them elasticity.

In children, organic substances predominate in the bone tissue; their skeleton is flexible, elastic, and therefore it is easily deformed, bent under prolonged and heavy load and incorrect body positions. As we age, the mineral content of bones increases, causing bones to become less elastic and more brittle.

Organic and mineral substances make the bone strong, hard and elastic, and in combination with the structural features of bone tissue, the location of its plates, oriented in the direction of pressure and tension forces, give the bone properties that surpass many building materials and metals. Thus, bone is 30 times harder than brick and 2.5 times harder than granite. Bone is stronger than oak. It is 9 times stronger than lead and almost as strong as cast iron.

The human femur in a vertical position can withstand the pressure of a load of up to 1.5 tons, and the tibia - up to 1.8 tons.

Growth and development of bones. Young bones grow in length due to the cartilage located between their ends and the body. By the end of bone growth, cartilage is replaced bone tissue. During the period of growth in the bones of the child, the amount of water decreases, and the amount of minerals increases. The content of organic matter is thus reduced.

The development of the skeleton in men ends by the age of 20-24. At the same time, the growth of bones in length stops, and their cartilaginous parts are replaced by bone tissue. The development of the skeleton in women ends 2-3 years earlier.

The structure and function of the joints. There are fixed, inactive and mobile joints of bones, or joints.

The fixed connection of the bones occurs by their fusion. Movement is extremely limited or non-existent. The immobility of the bones of the cerebral skull, for example, is achieved by the fact that the numerous protrusions of one bone enter the corresponding recess of the other. This connection of bones is called a seam.

Slight mobility is achieved by elastic cartilage pads between the bones. Such pads are located between individual vertebrae. When the muscles contract, these pads are compressed and the vertebrae come together. When walking, running, jumping, cartilage acts as a shock absorber, softening sharp shocks and protecting the body from concussion.

Movable joints of bones are more common, they are provided by true joints. The articulating ends of the bones are covered with hyaline cartilage 0.2–0.6 mm thick. This cartilage is elastic, has a smooth, shiny surface, which significantly reduces friction between the bones and thus facilitates their movement. The articulation area of ​​​​the bones is surrounded by an articular bag (capsule) of very dense connective tissue,

OPTION 1

OPTION 2

OPTION 1

1. Why are the skeleton and muscles referred to as a single organ system? What is the support, protection and motor function skeleton and muscles?

2. What does it matter fixed connection the bones of the skull, with the exception of the lower jaw?

3. In what ways are fixed, semi-movable and movable bone joints made?

4. How important are physical exercises for the normal development of the musculoskeletal system?

OPTION 2

1. What parts make up the musculoskeletal system? What are the structural features of the musculoskeletal system? What is the significance of the S-shaped bend of the human spine?

2. What is the chemical composition of bones? How can you find out the properties of its components?

3. What parts does the joint consist of, what functions do these parts perform?

4. Why are bone curvature more common in children, and fractures in the elderly? What should be done to avoid fractures and curvature?

OPTION 1

1. Why are the skeleton and muscles referred to as a single organ system? What are the supporting, protective and motor functions of the skeleton and muscles?

2. What is the immovable connection of the bones of the skull, with the exception of the lower jaw?

3. In what ways are fixed, semi-movable and movable bone joints made?

4. What is the importance of physical exercises for the normal development of the musculoskeletal system?

OPTION 2

1. What parts make up the musculoskeletal system? What are the structural features of the musculoskeletal system? What is the significance of the S-shaped bend of the human spine?

2. What is the chemical composition of bones? How can you find out the properties of its components?

3. What parts does the joint consist of, what functions do these parts perform?

4. Why are bone curvature more common in children, and fractures in the elderly? What should be done to avoid fractures and curvature?