Bones are living tissues composed of cells, proteins (mostly collagen), and minerals (calcium and phosphate). The skeletal system is made up of bones as well as cartilage and ligaments. Bones will develop longitudinally (lengthwise) until about the ages of 18 (for women) and 21 (for men), after which time humans will generally stop becoming taller. However, bone tissue is active and grows stronger when stressed. Exercise promotes a form of bone growth that generates bone thickening (appositional growth), which strengthens bones. When you sit on the couch, your bones weaken.
Organs are also protected by bones. Consider how easily your brain, spinal cord, heart, and lungs could be damaged if they were not protected by bone. Bone is an extremely strong bone that yet has considerable flexibility, making it the ideal tissue for its role.
Another key function of bones is hemopoiesis (hematopoeisis). Redbone marrow, which includes stem cells for the creation of all blood cells, is found in bone tissue. The stem cell is known as a hemocytoblast, and it is responsible for the formation of all red blood cells, white blood cells, as well as platelets. Red blood cells are essential for delivering oxygen and carbon dioxide throughout the body. The main biological component of the immune response is white blood cells, and platelets are required for hemostasis (blood clotting).
Structure of the skeletal system
The skeletal system is made up of all of the bones, cartilages, and ligaments in the body that support and shape the body and its structures. The skeleton is made up of the body’s bones. The skeleton of an adult contains 206 bones. Because some bones fuse throughout childhood and adolescence to shape an adult bone, younger people have more bones. The skeleton’s principal purposes are to create a hard, internal framework that can sustain the weight of the body against the force of gravity, as well as to offer a structure against which muscles can act to produce body movements. The skeleton has defensive and storing functions in addition to providing support and movement for the body. It safeguards internal organs such as the brain, spinal cord, heart, lungs, and pelvic organs. The skeleton’s bones are the major storage place for essential minerals including calcium and phosphorus. The bone marrow within bones stores fat and houses the body’s blood-cell-producing tissue. The skeleton is separated into two sections: axial and appendicular.
Components of the skeletal system
The skeletal system is made up of connective tissue, which includes bones, cartilage, and ligaments. The form of bones distinguishes them. Others are long, some are short, some are flat, and the remainder is shaped irregularly. There are two forms of osseous (bone) tissue. One is cancellous (also known as spongy bone owing to its sponge-like texture) and the other is compact bone, which is denser. Both types of bone are present in all bones (notice the distinction between bone tissue and bone), although compact bone (a tissue) is stronger and is always found on the outside of the bone.
All bone is made up of different types of bone cells. Osteocytes, osteoblasts, osteoclasts, as well as osteoprogenitor cells are all examples of these cells. They all have the prefix “osteo. The suffix “blast” signifies “to create,” whereas the suffix “clast” means “to destroy.” Osteoblasts are responsible for bone formation, whereas osteoclasts tear down bone and extract calcium. In this unit, these cells will be investigated in greater depth.
Aside from bones, cartilage and ligaments are two more components that are regarded to be constituents of the skeletal system. Hyaline cartilage is a form of cartilage that covers the ends of bones that move about one another. The portions of the bone surfaces that contact during these movements are referred to as articular surfaces (articulate means “to join”), and the hyaline cartilage in these locations is referred to as articular cartilage. It decreases friction and cushions the joint surfaces. Osteoarthritis is caused by the deterioration of this cartilage.
Hyaline cartilage is also necessary for long-term bone formation. It is not hyaline cartilage in this situation since it is not placed on the bone’s surface, but rather a thin band of hyaline cartilage inside the end of the long bone, in a location known as the epiphyseal plate (or growth plate). During development, the cartilage layer swells first and then develops into new bone tissue.
Ligaments are a type of dense connective tissue that is inelastic and very strong. Ligaments connect bones to offer stability to the joint. When a ligament is injured, it results in a sprain. Ligaments are white and are made up primarily of the structural protein collagen.
Conclusion
Humans are vertebrates, which are animals that have a vertebral column or backbone. They are supported by a strong internal frame that is centred on a noticeable spine. The human skeletal system is made up of bones, cartilage, ligaments, and tendons and accounts for around 20% of body weight. In metabolism, the living bones in our body use oxygen and emit waste products. They have active tissues that absorb nutrients, require a blood supply, and alter the form or remodel in response to mechanical stress fluctuations. The skeleton, which is made primarily of bones, is a strong structure that supports and protects the body’s soft organs. The skeleton protects the body from gravity’s pull. When standing, the massive bones of the lower limbs support the trunk.