Skeletal system

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The skeletal system consists of the bones and other connective tissues in the body. The main functions of the skeletal system are:

1. Provide structure and shape to the body. The bones provide a solid framework that shapes the body and protects internal organs.
2. Allow for movement. Muscles attach to bones, allowing us to move. The joints between bones also provide flexibility and movement in different directions.
3. Protect internal organs. The rib cage protects the heart and lungs, the skull protects the brain, and the vertebrae protect the spinal cord.
4. Produce blood cells. Red blood cells, white blood cells, and platelets are produced in the bone marrow inside bones.
5. Store minerals and fat. Bones store important minerals like calcium and phosphorus and fat for energy.
6. Anchor muscles. Muscles attach to bones, so the bones provide an anchoring point for muscles to exert forces.

The skeletal system consists of over 200 bones in an adult human. The major types of bones are:

• Long bones: longer than they are wide, include bones of the limbs.
• Short bones: roughly cube-shaped, include wrist and ankle bones.
• Flat bones: thin, provide protection or attachment for muscles, include bones of the skull and ribs.
• Irregular bones: complicated shapes, include vertebrae and hip bones.
• Sesamoid bones: embedded in tendons, include the patella or knee cap.

The bones are connected at joints, which can be immovable, slightly movable, or freely movable. Bones, cartilage, joints, and other connective tissues make up the skeletal system.

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Transcript:-
The entire framework of the human body constitutes the skeletal system. During early fetal life, the human skeleton is mostly cartilaginous and subsequently largely replaced by bones. It is made up of two primary groups of bones, namely the axial skeleton and the appendicular skeleton. The axial skeleton consists of the skull and the spinal vertebra column.

The appendicular skeleton consists of bones that make up the four limbs and hind limbs, and they're supporting skeletal framework, namely the pectoral girdle and the pelvic girdle. Bone is a highly specialized connective tissue, which forms the endoskeleton. The bone has an outer compact zone and an inner spongy zone.

The bone is provided with a matrix consisting of ossian protein, inorganic mineral salts, such as calcium phosphate, calcium carbonate, magnesium phosphate, and calcium fluoride, which give hardness to bone. Long bones, such as the femur, have a central cavity called marrow cavity containing yellow and red bone marrow.

The marrow cavity is lined by a thin layer of connective tissue endosteum, and the outer surface of bone is lined by periosteum. The bone cells, osteopaths and osteoclasts are embedded in the matrix in small pockets called le. The Osteocytes maintain indirect connections by the small canals called canale.

The unit of compact bone constitutes the aversion system, which consists of concentric layers of osteoblasts called bone lamella. They're Leni, interconnecting, canaliculi, and matrix. Those are circularly arranged around a narrow central lumen. The aversion canal bone makes up the skeletal framework of the body and gives rigidity as well as protection to vital organs.

Enclosed in the cranium and thoracic cavity. It provides the framework for the attachment of muscles and thus helps in movement and lo como. Yellow bone marrow is useful for storage of reserved food, whereas red bone marrow is responsible for the production of blood cells. The bones also serve as a reservoir of minerals, supplying calcium and phosphorus to the blood.

Osteoblasts produce new bone tissue, whereas osteoclasts dissolve the old tissues. So the bones keep their basic shape as they. This continuous and simultaneous construction and reabsorption of bone tissue is called bone remodeling. The cartilage is a tough and relatively flexible type of skeletal tissue, which is covered by a tough fibrous membrane called peron.

It consists of a matrix in which the cells and fibers are embedded. The matrix is composed of translucent and homogenous condron. In matrix. The cartilage cells or chondrocytes are found in small spaces called leni. There are three types of cartilages, namely hylan. Fibrous and elastic cartilage. The highland cartilage is found in larynx, trachea, and at the ends of bones with fibers that are not easily perceptible.

The fibrocartilage is found in the invertible discs and pubic synthesis with tough and opaque white fibers. The elastic cartilage is found in the external ear or pinna at the end of the nose in the epiglottis and utian tube with opaque and flexible yellow fibers, it supports and gives rigidity to the organs.

Cartilage provides surface for attachment of muscles and tendons at the ends of bones. It. Flexibility and relieves these bones from friction and shocks. It serves to keep the passages open and the organs dis tended whenever necessary. Joints are the place where two bones meet all bones except for one, the hyoid bone in neck form a joint with another bone joints hold the bones together and allow the rigid skeleton to.

The various types of joints are fixed joints, slightly movable joints, sternoclavicular and acromial, clavicular joints and synovial joints, fixed joints. Some joints like those in the skull are fixed and do not allow any movement. These bones are held together with fibrous connective tissue forming sutures.

Sutures allow for growth and very limited mobility. Slightly movable joints. The vertebrae in the spine are connected to each other by pads of cartilage called intervertebral discs, which permit limited mobility, sternal clavicular, and acromioclavicular joints. The clavicle or the collarbone is a slender curved bone of the pectoral girdle, which is attached to the sternum at one end and scapula at the other end.

These joints provide limited mobility. Most joints are synovial joints, which are movable joints containing a lubricating liquid called synovial fluid. Synovial joints are predominant in limbs where mobility is maximum. The most common synovial joints are ball and socket joints. These are the most mobile joint in the human body.

Examples, hip and shoulder joints. Ellipsoidal joints. These allow bending and extending, rocking from side to side, but rotation is limited. Example joint at the base of the index finger gliding joints. These occur between the surfaces of two flat bones that are held together by ligaments. Examples, some bones of the wrists and ankles move by gliding against each other.

Hinge joints. These enable movement similar to the opening and closing of a hinged door. Examples knee and elbow joints pivot joint. This occurs in the neck, which allows turning the head from side to side. Saddle joint thumbs, provide the best example. The bones in a saddle joint can rock back and forth and move from side to side, but they have limited rotation.

The entire group of bones that make up the head is called the skull, and it consists of two primary parts, a cranium and B facial area. Cranium is the rounded area that houses and protects the brain. It is composed of eight distinct bones that are fused together in an adult frontal. The frontal bone is the one that comprises the forehead, the upper orbit of the eye, and forward parts of the cranium.

The frontal bone is fused with the parietal bones, the sphenoid, maxilla, and nasal bones, parietal bones. There are two parietal bones which form the largest portion of the top sides of the cranium. They are fused at the top of the skull. The parietal bones are also joined to the sphenoid, temporal and occipital bones, temporal bones.

There are two distinct temporal bones that form the lower central sides of the skull. The temporal bones hold parts of the ears. Ethmoid bone. There is a single ethmoid bone, which is delicate, spongy, and is located between the eyes. It also forms a part of the frontal area of the cranium sphenoid bones.

There are two sphenoid bones and they are situated behind the eyes and run back towards the temporal bone. Occipital bone, there is only one occipital bone. It forms the back of the skull. There is a wide aperture, the Forin Magnum, through which the medulla Alan passes linking the brain to the spinal cord.

The facial area is made up of 14 bones, which include those that make up jaws, cheeks, and the nasal. Mandible or lower jaw is the only movable bone of the skull. There are two maxilla which comprise the upper jaw. There are two zygomatic bones that are placed on either side of the skull and comprise the higher area of the cheeks.

There are two small lacrimal bones that sit at the inside corner of each. There is a single vomer bone, and that is what forms the lower portion of the nasal septum. Nasal bones are a pair of small, slender bones that support the actual bridge of the nose. They are fused at the top to the frontal bone and to the maxilla inside the eye.

There are six tiny bones in three pairs called ossicles that are located in the ears. These are known as Malus, incus, and stapes, which are joined in such a way as to amplify the sound waves received by the Tim Panic membrane. Eardrum. The tongue is attached to a single U-shaped bone known as hyoid bone.

The hyoid is located underneath the skull and forms the boundary between the head and the neck. Although humans are born with 33 vertebra, certain parts of the vertebrae fused during development, resulting in 24 separate vertebrae and two fused bones. The spinal column is divisible into five regions, cervical, thoracic, lumbar, saccr, and kig.

The cervical region has seven vertebra. The first and second vertebra are modified into Atlas and axis to afford movement of the skull. Atlas supports the skull and allows a nodding movement, whereas AXIS allows skull rotation. There are 12 thoracic vertebra, which are modified for providing articulation to the ribs.

The thoracic vertebra are connected to the ribs and sternum, forming a thoracic cage, protecting heart and lungs. The lumbar region has five strongly built vertebra. The Sacro hip region has five fused vertebra forming a complete triangular bone called sacrum, which gives rigidity and support to the pelvic girdle.

The coxal region has the lowest four vertebra, which are fused to form the tailbone or coxy. All the elements of the spinal column and vertebra serve the purpose of protecting the spinal cord enclosed in the neural canal. The backbone or spine is also the powerhouse of the entire body, supporting the trunk and making all of the movements of head, arms, and legs possible.

The intervertebral Foren provides the passage for the spinal nerves and blood vessel. There are 12 pairs of ribs, which are slender, curved bars, movable, articulate with thoracic vertebra, dorsy, and unite with the sternum. Eventually all collectively forming the skeletal framework of the thorax called the thoracic cage, protecting the vital organs, the heart and the lungs.

The upper seven pairs of ribs are the true ribs because their costal cartilages articulate directly with the. The next three pairs of ribs are the false ribs because the costal cartilages of these ribs articulate anteriorly with the cartilages of the ribs above the next two pairs have no anterior connection with other ribs or the sternum, and are often called floating ribs.

Pectoral girdle is made up of a slender curved bone called clavicle or collarbone, and a flat scapula or shoulder bone. The scapula has a circular depression called glenoid cavity into which fits the head of the humus. Pelvic girdle is a strong structure supporting abdominal organs. It consists of two large hip bones, innominate bones.

Each innominate bone is formed of ileum ism and pubic bones, which are firmly connected to the sacrum by strong ligaments. It is strongly built to absorb the thrust transmitted by the legs while walking and running. The for limb consists of upper arm, forearm, wrist, and hand. The upper arm has a single bone humorous, whereas the forearm has two bones, the radius and ulna.

The wrist is supported by Carpals and metacarpals. The fingers of the hand are supported by the phalanges. The hind limb consists of thigh, shank and foot. The thigh has femur, which is the longest and strongest bone. The shank has two bones, the tibia and the fibula. The ankle is supported by Tarsals and metatarsals.

The five toes of the foot are supported by the phalanges. The skeletal system that not only provides the framework that supports the human body and protection for the vital internal organs, empowers movement while playing a vital role in blood cell formation and serving as storage for vital minerals.

This tough organ made up of various bones, cartilages, and joints. intricate structure and basic functions depicted through these animation videos are essential to further one's understanding of a system that is part of the complex organization of the human body.