Skeletal system

Learning Objectives By the end of this section, you will be able to: List and describe the functions of the skeletal system • Attribute specific functions of the skeletal system to specific components or structures The skeletal system is the body system composed of bones, cartilages, ligaments and other tissues that perform essential functions for the human body. Bone tissue, or osseous tissue, is a hard, dense connective tissue that forms most of the adult skeleton, the internal support structure of the body. In the areas of the skeleton where whole bones move against each other (for example, joints like the shoulder or between the bones of the spine), cartilages, a semi-rigid form of connective tissue, provide flexibility and smooth surfaces for movement. Additionally, ligaments composed of dense connective tissue surround these joints, tying skeletal elements together (a ligament is the dense connective tissue that connect bones to other bones). Together, they perform the following functions: Figure 6.1.1 Functions of the skeletal system. Support, Movement, and Protection Some functions of the skeletal system are more readily observable than others. When you move you can feel how your bones support you, facilitate your movement, and protect the soft organs of your body. Just as the steel beams of a building provide a scaffold to support its weight, the bones and cartilages of your skeletal system compose the scaffold that supports the rest of your body. Without the skel...

The skeletal system includes all of the bones and joints in the body. Each bone is a complex living organ that is made up of many cells, protein fibers, and minerals. The skeleton acts as a scaffold by providing support and protection for the soft tissues that make up the rest of the body. The skeletal system also provides attachment points for muscles to allow movements at the joints. New blood cells are produced by the red bone marrow inside of our bones. Bones act as the body’s warehouse for calcium, iron, and energy in the form of fat. Finally, the skeleton grows throughout childhood and provides a framework for the rest of the body to grow along with it. Skeletal System Anatomy The skeletal system in an adult body is made up of 206 individual bones. These bones are arranged into two major divisions: the axial skeleton and the appendicular skeleton. The axial skeleton runs along the body’s midline axis and is made up of 80 bones in the following regions: • Skull • Hyoid • Auditory ossicles • Ribs • Sternum • Vertebral column The appendicular skeleton is made up of 126 bones in the folowing regions: • Upper limbs • Lower limbs • Pelvic girdle • Pectoral (shoulder) girdle Skull The The bones of the superior portion of the skull are known as the cranium and protect the brain from damage. The bones of the inferior and anterior portion of the skull are known as facial bones and support the eyes, nose, and mouth. Hyoid and Auditory Ossicles The The malleus, incus, and stapes...

Human Skeletal System Skeletal System The skeletal system functions as the basic framework of a body and the entire body are built around the hard framework of Skeleton. It is the combination of all the bones and tissues associated with cartilages and joints. Almost all the rigid or solid parts of the body are the main components of the skeletal system. Joints play an important role in the skeletal system as it helps in permitting the different types of movements at different locations. If the skeleton were without joints, then there would be no sign of the movements in the human body. Skeletal System Anatomy This skeletal system can be divided into the axial and appendicular systems. In an adult body, it is mainly composed of 206 individual bones which are organized into two main divisions: • Axial skeleton • Appendicular skeleton. Axial skeleton The axial skeleton runs along the body’s central axis, therefore it is called the central core of the human body. The axial skeleton is composed of 80 bones and it consists of: • Skull Bone – It includes 8 cranial bones, 14 facial bones, 6 auditory ossicles, and the Hyoid Bone • The bone of the Thoracic Cage – It includes 25 bones of the thorax- a breastbone and 24 ribs. • The bone of the Vertebral column- It includes 24 vertebrae bones, the sacrum bone, and the coccyx bone. Also check: Appendicular skeleton The appendicular skeleton is composed of 126 bones and it comprises of the- • Pelvic girdle • Upper Limbs • Lower Limbs •...

CONTENTS • Skeletal System Definition • Overview • Function • Support • Integration with the Muscular System • Protection • Blood Cell Production • Production of other Cell Types • Storing Minerals • Parts • Bone • Joints • Cellular Composition • Structure • Diseases • Curvature of the Spine • Osteoporosis • Arthritis • Interesting Facts • Quiz Index Definition The skeletal system provides support and protection for the body’s internal organs and gives the muscles a point of attachment. Humans have an endoskeleton, where our bones lie underneath our skin and muscles. In other animals, such as insects, there is an exoskeleton on the outside of the body. Overview In humans, the skeletal system consists of bones, joints and associated cartilages. An adult human has 206 bones in their body and variety of different joints. Skeletal System Diagram Image shows a human skeleton with the major bones labeled. The human skeleton can be divided into two components: the axial skeleton and the appendicular skeleton. The axial skeleton is formed around the central axis of the body and thus includes the skull, Skeletal System Function Support The first and most apparent function of the skeletal system is to provide a framework for the body. The presence of a firm bony skeleton allows the organism to have a distinctive shape adapted towards a particular lifestyle. For instance, in a fast-moving animal like the cheetah, the skeleton contains long, thin limb bones and an extremely flexible s...

Skull and Cross-Bones The skull and cross-bones symbol has been used for a very long time to represent death, perhaps because after death and decomposition, bones are all that remain. Many people think of bones as being dead, dry, and brittle. These adjectives may correctly describe the bones of a preserved skeleton, but the bones of a living human being are very much alive. Living bones are also strong and flexible. Bones are the major organs of the skeletal system. Figure \(\PageIndex\): skull and cross-bones flag The skeletal system is the organ system that provides an internal framework for the human body. Why do you need a skeletal system? Try to imagine what you would look like without it. You would be a soft, wobbly pile of skin containing muscles and internal organs but no bones. You might look something like a very large slug. Not that you would be able to see yourself — folds of skin would droop down over your eyes and block your vision because of your lack of skull bones. You could push the skin out of the way if you could only move your arms, but you need bones for that as well! Components of the Skeletal System In adults, the skeletal system includes 206 bones, many of which are shown in Figure \(\PageIndex\): Some of the 206 bones are labeled on the adult human skeleton. Besides bones, the skeletal system includes cartilage and ligaments. • Cartilage is a type of dense connective tissue, made of tough protein fibers. It is strong but flexible and very smooth....