Lab 4: Skeletal System I – Bone Tissue and Axial Skeleton
Lab 4: Skeletal System I – Bone Tissue and Axial Skeleton
Bone structures, Axial Skeleton
When you are prepared for the Test on Week 4 Learning Objectives in Week 5, you will be able to:
- Identify components of long bone structure and their functions.
- Identify components of bone tissue.
- Identify zones of the epiphyseal plate and describe how the activities in each zone contribute to bone growth.
- Identify the bones of the axial skeleton, including all of those in the skull.
- Identify some of the important morphological features of the skull, which bones they are located in, and their functions (listed in the lab activity).
- Identify the major sutures of the skull and fontanels of the infant skull.
- Identify the major regions of the vertebral column, the rib cage, and the sternum.
The skeletal system forms the rigid internal framework of the body. It consists of the bones, cartilages, and ligaments. Bones support the weight of the body, allow for body movements, and protect internal organs. Cartilage provides flexible strength and support for body structures such as the thoracic cage, the external ear, and the trachea and larynx. At joints of the body, cartilage can also unite adjacent bones or provide cushioning between them. Ligaments are the strong connective tissue bands that hold the bones at a moveable joint together and serve to prevent excessive movements of the joint that would result in injury. Providing movement of the skeleton are the muscles of the body, which are firmly attached to the skeleton via connective tissue structures called tendons. As muscles contract, they pull on the bones to produce movements of the body. Thus, without a skeleton, you would not be able to stand, run, or even feed yourself!
The Functions of the Skeletal System
Bone, or osseous tissue, is a hard, dense connective tissue that forms most of the adult skeleton, the support structure of the body. In the areas of the skeleton where bones move (for example, the ribcage and joints), cartilage, a semi-rigid form of connective tissue, provides flexibility and smooth surfaces for movement. The skeletal system is the body system composed of bones and cartilage and performs the following critical functions for the human body:
- supports the body
- facilitates movement
- protects internal organs
- produces blood cells
- stores and releases minerals and fat
Support, Movement, and Protection
The most apparent functions of the skeletal system are the gross functions—those visible by observation. Simply by looking at a person, you can see how the bones support, facilitate movement, and protect the human body.
Just as the steel beams of a building provide a scaffold to support its weight, the bones and cartilage of your skeletal system compose the scaffold that supports the rest of your body. Without the skeletal system, you would be a limp mass of organs, muscle, and skin.
Bones also facilitate movement by serving as points of attachment for your muscles. While s