Chapter 22 Introduction to Body Systems Skeletal, Muscular, and Integumentary Systems
Section 1: Objectives • Describe how tissues, organs, and organ systems are related. • List 12 organ systems. • Identify how organ systems work together to maintain homeostasis.
Introduction to Organ Systems • The many kinds of cells in your body help your internal environment stay stable. • The maintenance of a constant internal state in a changing environment is called homeostasis.
Introduction to Organ Systems • A group of similar cells working together forms a tissue. • Your body has four main kinds of tissue.
Introduction to Organ Systems • Two or more tissues working together to carry out a specialized function form an organ.
Introduction to Organ Systems • Organs that work together make up an organ system. • Organ systems work together to maintain homeostasis. • Your body has 12 major organ systems.
Section 2: Objectives • Identify the major organs of the skeletal system. • Describe four functions of bones. • Describe three types of joints. • List three injuries and two diseases that affect bones and joints.
The Skeletal System • Bones, cartilage, and the connective tissue that holds bones together make up your skeletal system. • Bone tissue without any visible open spaces is called compact bone. • Bone tissue that has many open spaces is called spongy bone. • Bones contain a soft tissue called marrow. • Most bones start out as a flexible tissue called cartilage. • Eventually, most cartilage is replaced by bone.
The Skeletal System • A place where two or more bones meet is called a joint. • Joints are held together byligaments.
The Skeletal System • Bones may be fractured or broken. • Ligaments can be stretched or torn. • Arthritis is a disease that causes the joints to swell or stiffen. • Osteoporosis is a disease that causes bones to become less dense.
Chapter 22 Sec. 1-2 Recap • 1) List 1 way the different types of cells in your body work together. • 2) T/F Your body has 1 type of tissue. • 3) List the 3 parts of the skeletal system. • 4) What is cartliage? • 5) What is the function of ligaments? • 6) T/F Ligaments can be stretched but not torn. • 7) Bones can be broken or fractured.
Section 3: Objectives • List three kinds of muscle tissue. • Describe how skeletal muscles move bones. • Compare aerobic exercise with resistance exercise. • Describe two muscular system injuries.
The Muscular System • The muscular system is made up of the muscles that let you move. • Involuntary muscle found in the digestive tract and the walls of the blood vessels is calledsmooth muscle. • Involuntary muscle found in your heart is called cardiac muscle. • Muscle attached to your skeleton for movement is calledskeletal muscle. • Skeletal muscle can be voluntary or involuntary.
The Muscular System • Tendons are strands of tough connective tissue that connect your skeletal muscles to your bones. • Skeletal muscles often work in pairs. • A muscles that bends part of your body is called a flexor. • A muscle that straightens part of your body is an extensor.
The Muscular System • During resistance exercise, people work against the resistance, or weight, of an object to strengthen their skeletal muscles. • Steady, moderately intense activity is called aerobic exercise, and strengthens the heart and increases endurance.
The Muscular System • A strain is an injury in which a muscle or tendon is overstretched or torn. • People who exercise too much can hurt their tendons. Inflamed tendons is called tendonitis. • Some people try to make their muscles stronger by taking drugs. These drugs are called anabolic steroids and can cause long-term health problems.
Section 4: Objectives • List four functions of skin. • Describe the two layers of skin. • Describe the structure and function of hair and nails. • Describe two kinds of damage that can affect skin.
The Integumentary System • Your skin, hair, and nails make up your integumentary system. • Skin protects you by keeping water in your body and foreign particles out of your body. • Nerve endings in your skin let you feel things around you. • Skin helps regulate your body temperature and also helps get rid of waste chemicals.
The Integumentary System • The epidermis is the outermost layer of skin. • Most cells in the epidermis are dead. • The thicker layer of skin that lies beneath the epidermis is the dermis.
The Integumentary System • A hair forms at the bottom of a tiny sac called a hair follicle. • Hair helps protect skin from ultraviolet light and helps regulate body temperature in most mammals. • A nail grows from living cells in the nail root at the base of the nail. • Nails protect the tips of your fingers and toes.
The Integumentary System • Skin is often damaged, but fortunately can repair itself. However, damage to the genetic material in skin cells can cause skin cancer.