Category: Skeletal System

Here is what we have learned from Introduction to the Skeletal System: The human skeleton is well-adapted for the functions it must perform. Functions of bones include support, protection, movement, mineral storage, and formation of blood cells. There are two types of bone tissue: compact and spongy. Compact bone consists of closely packed osteons, or haversian…

Most joints in the adult body are diarthroses, or freely movable joints. The singular form is diarthrosis. In this type of joint, the ends of the opposing bones are covered with hyaline cartilage, the articular cartilage, and they are separated by a space called the joint cavity. The components of the joints are enclosed in a dense fibrous…

Slightly movable joints are called amphiarthroses. The singular form is amphiarthrosis. In this type of joint, the bones are connected by hyaline cartilage or fibrocartilage. The ribs connected to the sternum by costal cartilages are slightly movable joints connected by hyaline cartilage. The symphysis pubis is a slightly movable joint in which there is a fibrocartilage pad between the two bones. The joints between…

Synarthroses are immovable joints. The singular form is synarthrosis. In these joints, the bones come in very close contact and are separated only by a thin layer of fibrous connective tissue. The sutures in the skull are examples of immovable joints.

An articulation, or joint, is where two bones come together. In terms of the amount of movement they allow, there are three types of joints: immovable, slightly movable and freely movable.

Pectoral girdles Clavicle (2) Scapula (2) Upper Extremity Humerus (2) Radius (2) Ulna (2) Carpals (16) Metacarpals (10) Phalanges (28) Pelvic Girdle Coxal, innominate, or hip bones (2) Lower Extremity Femur (2) Tibia (2) Fibula (2) Patella (2) Tarsals (14) Metatarsals (10) Phalanges (28)

Skull (28) Cranial Bones Parietal (2) Temporal (2) Frontal (1) Occipital (1) Ethmoid (1) Sphenoid (1) Facial Bones Maxilla (2) Zygomatic (2) Mandible (1) Nasal (2) Platine (2) Inferior nasal concha (2) Lacrimal (2) Vomer (1) Auditory Ossicles Malleus (2) Incus (2) Stapes (2) Hyoid (1) Vertebral Column Cervical vertebrae (7) Thoracic vertebrae (12) Lumbar vertebrae…

The adult human skeleton usually consists of 206 named bones. These bones can be grouped in two divisions: axial skeleton and appendicular skeleton. The 80 bones of the axial skeleton form the vertical axis of the body. They include the bones of the head, vertebral column, ribs and breastbone or sternum. The appendicular skeleton consists of 126 bones and includes the free appendages and their…

Long Bones The bones of the body come in a variety of sizes and shapes. The four principal types of bones are long, short, flat and irregular. Bones that are longer than they are wide are called long bones. They consist of a long shaft with two bulky ends or extremities. They are primarily compact bone but…

Bones grow in length at the epiphyseal plate by a process that is similar to endochondral ossification. The cartilage in the region of the epiphyseal plate next to the epiphysis continues to grow by mitosis. The chondrocytes, in the region next to the diaphysis, age and degenerate. Osteoblasts move in and ossify the matrix to form…