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Skeletal, Muscular, and Nervous Systems
The Skeletal System
Care and Problems of the Skeletal System
The Muscular System
The Nervous System
Care and Problems of the Nervous System
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Before You Read Use this Foldable to help you organize your notes on the structure and function of the skeletal system, muscular system, and nervous system. Begin with three 1 sheets of 8 ⁄2 x 11 paper.
Fold the sheets of paper along the long axis so that one edge is about 1 from the other.
Fold the paper in half. Unfold and cut along the inside fold line.
Repeat with the other two sheets of paper. Label as shown. Staple the sheets together.
Muscular System Structure Function
Skeletal System Nervous System Structure Function Structure Function
As You Read As you read and discuss the material in the chapter, use your Foldable to record what you learn.
Using Visuals. The skeletal, muscular, and nervous systems are fine-tuned to work together, allowing the body to perform a variety of coordinated actions. What steps do you take in your day-to-day activities to keep these systems functioning and to protect them from injury?
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The Skeletal System
VOCABULARY YOU’LL LEARN TO axial skeleton • Identify the functions of the skeletal system. appendicular skeleton • Describe the main divisions and types of bones of the cartilage skeletal system. ossification ligament • Recognize how understanding the functions of the skeletal tendon system is important for maintaining personal health.
List three health behaviors that you think are important for keeping your skeletal system healthy. How do these behaviors help maintain strong bones?
ou reach out your arm and hit the snooze button; it’s Y6:00 a.m.—time to rise and shine. As you roll out of bed, you reach your arms above your head, stretching your arms and back and rolling your shoulders. You are able to start your day thanks to the interrelationships of your skeletal, muscular, and nervous sys- tems. In this lesson you’ll learn about the system that provides the basic framework for your body, your skeletal system. Functions of the Skeletal System our skeletal system provides a living structure for your body. YStrong bones, including the vertebrae of your spine, support your upper body and head. The skeleton plays a crucial role in movement by providing a strong, stable, and mobile framework on which muscles can act. Your skeletal system also protects your internal tissues and organs from trauma. The skull, vertebrae, and ribs create protective cavities for the brain, the spinal cord, and the The interaction of bones heart and lungs, respectively. Bones store minerals such as calcium and muscles allows you to perform all kinds of and phosphorus, which are important to the health and strength of motions. List three the skeleton and to various essential processes in your body. Bone functions of the marrow, a connective tissue within bones, produces new red blood skeletal system. cells and white blood cells.
386 Chapter 15 Skeletal, Muscular, and Nervous Systems Structure of the Skeleton Bone tissue consists of living cells embedded in our skeletal system consists of 206 bones that can be classi- a hard matrix of calcium, Yfied in two main groups. The axial skeleton consists of the phosphate, and other 80 bones of the skull, spine, ribs, vertebrae, and sternum, or breastbone. calcium minerals. The appendicular skeleton is composed of the remaining 126 bones of the upper and lower limbs, shoulders, and hips. The bones of cartilage these two groups are shown in Figure 15.1 on page 388. marrow cavity Types of Bones compact bone All bones are covered with an outer layer of hard, densely packed, spongy bone compact bone. Beneath the compact bone is spongy bone, a less dense bone with a network of cavities filled with red bone marrow. Almost every bone in the body can be placed in the following categories by shape, as shown in the illustration: