Skeletal System-part 1.pdf

The Skeletal...

The Skeletal System: Parts, Divisions, Classifications, Photo: (LaPres, J. et al. (2016). Gunstream’s Anatomy and Physiology (6 th ed.). Mc-Graw Hill. and Articulations  The Skeletal System “The human skeleton is an ACTIVE and LIVING TISSUE that performs simple to complex functions” (American Council on Exercise, p. 11)  The Skeletal System ∙ The human body has a total of 206 bones, most of which are paired– right and left arm/leg (American Council on Exercise, p. 11). (LaPres, J. et al. (2016). Gunstream’s Anatomy and Physiology (6th ed.). Mc-Graw Hill.  The Skeletal System ∙ Parts of the skeletal system ∙ Bones (skeleton) ∙ Joints ∙ Cartilages ∙ Ligaments (bone to bone)(tendon= bone to muscle) (LaPres, J. et al. (2016). Gunstream’s Anatomy and Physiology (6th ed.). Mc-Graw Hill.  Overall Functions of Bones ∙ Support of the body ∙ Protection of soft organs ∙ Movement due to attached skeletal muscles ∙ Storage of minerals and fats ∙ Blood cell formation (LaPres, J. et al. (2016). Gunstream’s Anatomy and Physiology (6th ed.). Mc-Graw Hill.  Bones of the Human Body ∙ Two basic types of bone tissue ∙ Compact bone ∙ Homogeneous ∙ Spongy bone ∙ Small needle-like pieces of bone ∙ Many open spaces Figure 5.2b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Classification of Bones on the Basis of Shape Figure 5.1 (LaPres, J. et al. (2016). Gunstream’s Anatomy and Physiology (6th ed.). Mc-Graw Hill.  Bones are classified by their shape: 1. Long- bones are longer than they are wide (arms, legs) 2. Short- usually square in shape, cube like (wrist, ankle) 3. Flat- flat , curved (skull, Sternum) 4. Irregular- odd shapes (vertebrae, pelvis) (LaPres, J. et al. (2016). Gunstream’s Anatomy and Physiology (6 th ed.). Mc-Graw Hill.  Types of Bone Cells ∙ Osteocytes ∙ Mature bone cells ∙ Osteoblasts ∙ Bone-forming cells ∙ Osteoclasts ∙ Bone-destroying cells ∙ Break down bone matrix for remodeling and release of calcium ∙ Bone remodeling is a process by both osteoblasts and osteoclasts (LaPres, J. et al. (2016). Gunstream’s Anatomy and Physiology (6th ed.). Mc-Graw Hill.  Changes in the Human Skeleton ∙ In embryos, the skeleton is primarily hyaline cartilage ∙ During development, much of this cartilage is replaced by bone ∙ Cartilage remains in isolated areas ∙ Bridge of the nose ∙ Parts of ribs ∙ Joints (LaPres, J. et al. (2016). Gunstream’s Anatomy and Physiology (6th ed.). Mc-Graw Hill.  Divisions of the Skeleton The human adult skeleton is composed of two distinct divisions: the axial skeleton and the appendicular skeleton. The axial (ak -se¯-al) skeleton consists of the bones along the longitudinal axis of the body that support the head, neck, and trunk (LaPres et al., 2016). The appendicular (ap-en-dik -u¯- lar) skeleton consists of the bones of the upper limbs and pectoral girdle and of the lower limbs and pelvic girdle (LaPres et al., 2016). Knowledge of surface bony features is essential for understanding the origins and insertions of skeletal muscles discussed in the muscular system (LaPres et al., 2016).. A CLOSER LOOK… (LaPres, J. et al. (2016). Gunstream’s Anatomy and Physiology (6 th ed.). Mc-Graw Hill.  The Axial Skeleton ∙ Forms the longitudinal part of the body ∙ Divided into three parts ∙ Skull ∙ Vertebral Column ∙ Rib Cage (LaPres, J. et al. (2016). Gunstream’s Anatomy and Physiology (6th ed.). Mc-Graw Hill.  The Appendicular Skeleton Bones of limbs and bones that anchor them to the axial skeleton. Appendicular skeleton: pectoral girdle (clavicle, scapula) upper limbs (arms) pelvic girdle (sacrum, coccyx) lower limbs (legs) Articulation- where joints meet, connect, and are formed. (LaPres, J. et al. (2016). Gunstream’s Anatomy and Physiology (6th ed.). Mc-Graw Hill.  Articulations: Joints A joint, or articulation, is the place where two bones come together. Fibrous- Immovable:connect bones, no movement. (skull and pelvis). Cartilaginous- slightly movable, bones are attached by cartilage, a little movement (spine or ribs). Synovial- freely movable, much more movement than cartilaginous joints. Cavities between bones are filled with synovial fluid. This fluid helps lubricate and protect the bones.  Immovable Joint (LaPres, J. et al. (2016). Gunstream’s Anatomy and Physiology (6th ed.). Mc-Graw Hill.  Synovial Joint (Freely Movable) At these joints, the articulating bone surfaces are covered with articular cartilage, an articular capsule surrounds the joint, and a synovial membrane lining the interior of the joint capsule secretes a lubricant known as synovial fluid (Hall, 2022).  Types of Synovial Joints Based on Shape (LaPres, J. et al. (2016). Gunstream’s Anatomy and Physiology (6th ed.). Mc-Graw Hill.  Types of Synovial Joints Based on Shape (LaPres, J. et al. (2016). Gunstream’s Anatomy and Physiology (6th ed.). Mc-Graw Hill.  More examples of Synovial Joints: (American Council on Exercise, p. 16). Major Joints in the Body (American Council on Exercise, p. 17).  Reference American Council on Exercise (Chapter 1). Hall, S. (2022). Basic Biomechanics. LaPres, J. et al. (2016). Gunstream’s Anatomy and Physiology (6th ed.). Mc-Graw Hill.