Nursing Entrance Exam

Nursing Preparation Study Guide the external ear. Fibrous cartilage , also called fibrocartilage, provides tensile strength and shock absorption, and is found in intervertebral discs. Cartilage becomes bone through a process called ossification. There are a number of different types of bones, and they are classified according to shape, structure, and surface markings. A bone may be categorized by its general shape or by its internal tissue organization. The early skeleton forms during gestation and continues to develop for several years after birth through a process called endochondral ossification. A baby has more than 300 bones, whereas an adult only has 206, as several bones fuse together during growth. They can be divided into six broad categories according to their shapes: long, flat, sutural, irregular, short, and sesamoid. There are different cells involved in producing bones and these cells are located in the matrix of the bone. This matrix also contains a variety of substances and collagen. As this matrix hardens, bone forms. Bone is composed of a matrix and several types of cells: osteocytes , osteoblasts , osteoprogenitor cells , and osteoclasts . The formation, reformation, and repair of bones takes place over a long period of time. Muscles, tendons, ligaments, and cartilage support the skeleton; together, these are the musculoskeletal system. There are several differences between male and female skeletons, including the pelvis, which has to allow for childbirth. 6.4.1 Functions • Supports the body and maintains the shape of the body • The joints between the bones allow movement • Protects organs (e.g., such as the skull protecting the brain, eyes, and inner ears) • Produces cells in its bone marrow (hematopoiesis) • The skeleton stores a variety of substances, including calcium and iron • Is also involved in the regulation of blood sugar levels and fat deposits through the release of a hormone called osteocalcin 6.4.2 Components Skeleton: The skeleton consists of the axial skeleton and the appendicular skeleton. The axial skeleton is comprised of central bones, including the skull, vertebrae, and rib cage. The appendicular skeleton consists of the pelvis, and upper and lower limbs. Bone: Two types of bone structure make up the skeleton: • Compact, or dense, bone is the majority of the adult skeleton, and it has a smooth, white appearance • Cancellous, or trabecular, bone is the spongey bone tissue found inside compact bones. This contains room for blood vessels and marrow.

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