Bones, Muscles & Skin

Life Science - Middle School

Bones, Muscles and Skin © C opyright NewPath Learning. All Rights Reserved. 94-4901 hair nerve sweat gland oil gland hair follicle muscle blood vessels fat dermis epidermis The Skeletal System There are ve major functions of the skeletal system: 1. Enables you to move around 2. Protects internal organs 3. Provides support and determines the shape of your body 4. Stores materials 5. Produces blood cells The structure of a bone consists of an outer layer of hard connective tissue. Beneath the outer layer is the compact bone tissue followed by the spongy bone tissue. The spongy bone tissue gives the bone its lightweight and provides strength. The spaces within the bone are lled with marrow, a soft connective tissue within bones. The two types of marrow are yellow and red. The yellow marrow stores fat and other materials to use for energy when necessary. The red marrow produces blood cells for the body. Cartilage is a connective tissue that is exible and strong, but softer than bone. Cartilage covers the ends of many bones and acts like a cushion, protecting the bones from being damaged. The Muscular System Muscles that you are able to control are called voluntary muscles. Muscles that you are not able to control are called involuntary muscles. Types of muscles There are three types of muscle tissue in the human body: skeletal muscle, smooth muscle and cardiac muscle. Skeletal muscles are voluntary muscles that are attached to the bones of your skeleton. These muscles provide you with the ability to move. At each end of a muscle is a strong connective tissue that attaches your muscles to bones called a tendon. Smooth muscles are involuntary muscles that are on the insides of internal organs. These muscles work automatically to control many functions of the body. Cardiac muscle has characteristics in common with both skeletal and smooth muscles. The Skin The skin covers the body, prevents water loss, gathers information from the environment, eliminates waste, protects the body from injury and infection, produces vitamin D, and regulates the body’s temperature. There are two main layers of the skin: the dermis and the epidermis. The dermis is the inner layer of skin, just above a layer of fat, which contains nerves, blood vessels, hairs, oil glands, and sweat glands. The epidermis is the outermost layer of skin that is thinner than the dermis and does not contain blood vessels or nerve cells. hinge Types of joints Every place in your body where two bones come together is called a joint. The body has four kinds of movable joints ball and socket, hinge, pivot, and gliding joints. Immovable joints are joints between bones that do not allow movement. Examples of immovable joints are the joints between the bones of the skull. gliding ball & sock et pivot spongy bone compact bone connective tissue cartilage ligaments cardiac muscle skeletal muscle smooth muscle tendon
\|xiBAHBDy01776pzY Bones, Muscles and Skin © C opyright NewPath Learning. All Rights Reserved. 94-4901 The Skeletal System What are the ve major functions of the skeletal system? 1. _____________________________________________________ 2. _____________________________________________________ 3. _____________________________________________________ 4. _____________________________________________________ 5. _____________________________________________________ The Muscular System What are voluntary muscles? _______________________________________________________ _______________________________________________________ What are involuntary muscles? _______________________________________________________ _______________________________________________________ Types of muscles Describe the 3 types of muscles; Skeletal ________________________________________________ Smooth ________________________________________________ Cardiac ________________________________________________ The Skin What is the function of the skin? __________________________________________ __________________________________________ Types of joints What is the difference between movable and immovable joints? _____________________ _____________________ _____________________ _____________________ _____________________ What is cartilage? _____________ ____________________________ ____________________________ ____________________________ Key Vocabulary Terms ball & socket gliding joint skeletal muscle cardiac muscle hair follicle smooth muscle cartilage hinge joint spongy bone compact bone involuntary sweat gland connective tissue ligament dermis marrow epidermis pivot joint