How many bones there are in the human body, how many bones do people have

There are a total of 206 bones in the human body. It can be divided into two categories: exoskeleton and endoskeleton. It provides protection and support for the soft tissues of the animal body, as well as the basis for attachment to the muscles, constituting a system of connected levers that can be moved.

The three closely related parts of bones, joints and muscles make up the animal's locomotor apparatus. The completion of various movements in animals is mainly the result of muscle contractions acting on the bones. Exercise is done with bones as levers, joints as hubs, and muscle contractions as power.

The function of bones is mainly for muscles to attach to, as a lever for the movement of the animal body; Support the body and maintain a certain body shape; Protects the soft organs in the body, such as the skull protects the brain and medulla, the thoracic cage protects the heart and lungs, etc.; Assist in maintaining the normal metabolism of calcium and phosphorus in the body; The red bone marrow in the bone marrow cavity has the function of making blood cells. The bone is divided into compact bone and cancellous bone. Compact bone is composed of neatly arranged bone plates, the bone plates arranged on the bone surface are the outer ring bone plates, the inner ring bone plates arranged around the bone marrow cavity are arranged inside, and there are many bone plates arranged in concentric circles between the inner and outer bone plates, which are called Havers' system, and its central tube is called Havers's canal.

Inside the duct there are blood vessels and nerves passing through. Compact bone mainly forms the backbone of long bones. Cancellous bone is spongy and is also known as spongy bone.

A reticular structure is formed by many bone trabeculae, and bone marrow is present within the mesh. The arrangement of these trabeculae corresponds to the direction of the force. Cancellous bone is found in the epiphysis of long bones, inside short bones, and irregular bones.

The bone marrow cavity is located between the diaphysis** and cancellous bone. Outside the bone there is a periosteal coating formed by connective tissue, which contains blood vessels and nerves. The periosteum plays an important role in the growth of bone and the repair of fractures.

Due to the different roles of each bone block in the body, it can be divided into 4 types: long bones, short bones, flat bones and irregular bones: Long bones, usually tubular and thick at both ends, are mainly found in the limbs, such as the femur and humerus, and play the role of support and leverage. The ribs belong to the long arcuate bones, which are long and curved and do not have a bone marrow cavity.

Short bones, square or round ossicles, such as carpal and tarsal bones, are bony and play a role in dispersing pressure and changing the direction of force. Flat bones, flattened plate-like bones, such as the bony pieces of the skull, play a role in protecting the brain. Irregular bones do not belong to the above types, and irregular shapes belong to irregular bones, such as petrosoid mastoid bones.

According to the different occurrences**, hard bones can be divided into two types: cartilaginous bone and membranous bone: cartilaginous bone. From mesenchyme, it passes through the cartilage stage and then becomes hard bone, called cartilaginous bone or replacement bone, for example, the spine, ribs, limb bones, and part of the skull.

Membranous bone. On the basis of mesenchyme, hard bones are directly formed without going through the cartilage stage, called membranous protoskeleton or cortical hard bones, for example, the frontal bone at the top of the skull, the parietal bone, the premaxilla, maxilla, and dental bones on the jaw arch. Chontilaginous bone and membranous bone are only distinguished according to the occurrence of **, and once they become hard bones, they are not easy to distinguish from morphology or nature.

There are a total of 206 bones in the human body. Among them, there are 29 skull bones, 51 trunk bones, and 126 four femurs. Because bones have different positions and functions in various parts of the human body, they are also known in various shapes, which are called long bones, short bones, flat bones, and irregular bones.

The long bones are long cylindrical, the longer section in the middle is called the backbone, and the two ends of the long bones are relatively expanded, which is called the epiphysis. The cavity inside the diaphysis is called the bone marrow cavity, and there is bone marrow inside. The bone marrow has a hematopoietic function.

Long bones are mostly distributed in the limbs, such as the ulna, radius, femur, etc. Most of the short bones are cubes, such as the tarsal bones and carpal bones. The flat bones are mostly wide and flat, plate-like, such as the parietal bones of the skull and the shoulder blades.

Irregular bones are irregular in shape, such as vertebrae. Bones are connected to each other mainly by joints. The larger joints in the human body include shoulder joints, elbow joints, radial joints, hip joints, knee joints, etc.

Joints generally consist of articular surfaces, articular cavities, and joint capsule.

The human body has a total of 206 bones, which are divided into three parts: the skull, the torso, and the limbs. They are distributed throughout the body, supporting the body, protecting the internal organs, and at the same time being supported by muscles for various activities.

All bones in the human body vary in shape and size, some are large, such as the tibia, humerus, etc., and some are small, such as the phalanges. In terms of shape, it can be roughly divided into five types: long bones, short bones, flat bones, irregular bones, and air-containing bones.

Flattened bones protect internal organs, such as the skull to protect the brain; The rod bone is responsible for the movement of the body, like the bones of the limbs, etc.

The human skeleton is composed of 206 bones, including 29 skulls, 51 trunk bones, and 126 limb bones.

There are about 639 muscles in the whole body. It is composed of about 6 billion muscle fibers, of which the longest muscle fiber is 60 centimeters, and the shortest is only about 1 millimeter.

Large muscles weigh 2,000 grams, while smaller muscles weigh only a few grams.

The average person's muscles make up 35-45% of their body weight. The total length of capillaries in the muscles can reach 100,000 kilometers, which can circle the earth two and a half times.

23 skulls (3 pairs of ossicles of the middle ear are not counted).

There are 8 skull bones: unpaired ones include frontal bones, ethmoid bones, sphenoid bones, and occipital bones.

Pairs include temporal bones and parietal bones.

There are 15 facial skulls: pairs include maxilla, palatine, zygomatics, nasal bones, lacrimal bones and inferior turbinates.

Unpaired ones include vomer, mandible, hyoid bone.

The trunk bones (40 pieces) include 24 vertebrae (7 cervical vertebrae, 12 thoracic vertebrae, 5 sternal vertebrae of the lumbar vertebrae, 1 sacrum (5 sacral vertebrae fused to form a coccyx, 12 ribs.

Upper limbs: 2 clavicles, 2 scapula, 2 humerus, 2 ulnas, 2 radius.

Hand bones: including 8 carpal bones: scaphoid bone, lunate bone, triangular bone, pea bone, most horn bone and small polygonal bone, capitate bone, hook bone.

Metacarpal 5 pieces: 1st 5th metacarpal bone.

There are 14 phalanges: the thumb is divided into two proximal and distal phalanxes, and the rest are divided into three segments (proximal phalanx, middle phalanx, and distal phalanx).

Lower limb bones: 2 hip bones.

2 femurs. 2 tibiae.

Fibula 2. 2 patellas.

Foot bones: These include the tarsal bones, metatarsals, and phalanges.

There are 7 tarsal bones: talus, calcaneus, navicular bone, medial cuneiform, intermediate cuneiform, lateral cuneiform and dice in front of the calcaneus.

The metatarsal 5 pieces are 1 5 metatarsals from the medial to the lateral side at a time.

14 phalanges.