Section 1 The Human Body Plan Chapter 45 Objectives • Describefour types of tissues that make up the human body. • Explainhow tissues, organs, and organ systems are organized. • Summarizethe functions of the primary organ systems in the human body. • Identifythe five human body cavities and the organs that each contains.

Section 1 The Human Body Plan Chapter 45 Body Tissues • All tissues are a collection of cells that have a similar structure and that work together to perform a particular function. • Muscle Tissue • Muscle tissue is composed of cells that can contract in a coordinated fashion.

Section 1 The Human Body Plan Chapter 45 Body Tissues, continued • Muscle Tissue, continued • The human body has three types of muscle tissue: skeletal, smooth, and cardiac. • Skeletal muscle moves the bones in your trunk, limbs, and face. • Smooth muscle handles body functions that you cannot control consciously. • Cardiac muscle, found in your heart, pumps blood through your body.

Section 1 The Human Body Plan Chapter 45 Body Tissues, continued • Nervous Tissue • Nervous tissue contains cells, or neurons, that receive and transmit messages in the form of electrical impulses. • Neurons are nerve cells that are specialized to receive and send electrical impulses.

Section 1 The Human Body Plan Chapter 45 Body Tissues, continued • Nervous Tissue, continued • Nervous tissue can be found throughout the human body and has various functions. • For example, nervous tissue can be found in the brain and sensory organs and is used to interpret sensory information.

Section 1 The Human Body Plan Chapter 45 Body Tissues, continued • Epithelial Tissue • Epithelial tissue is tissue that is composed of a sheet of cells and that covers a body surface or lines a body cavity. • Epithelial tissue is found in various thicknesses and arrangements, depending on where it is located.

Section 1 The Human Body Plan Chapter 45 Body Tissues, continued • Epithelial Tissue, continued • Each epithelial layer is formed from cells that are tightly bound together, often providing a protective barrier for these surfaces.

Section 1 The Human Body Plan Chapter 45 Body Tissues, continued • Connective Tissue • Connective tissue is a tissue that has a lot of intracellular substance and that connects and supports other tissues.

Section 1 The Human Body Plan Chapter 45 Body Tissues, continued • Connective Tissue, continued • Connective tissues are the most abundant and diverse of the four types of tissue and contain a substance called matrix. • Matrix is an intracellular substance that gives connective tissue its strength and flexibility and can be solid, semisolid, or liquid.

Section 1 The Human Body Plan Chapter 45 Human Body Tissues

Section 1 The Human Body Plan Chapter 45 Body Tissues Click below to watch the Visual Concept. Visual Concept

Section 1 The Human Body Plan Chapter 45 Organs and Organ Systems • An organ consists of various tissues that work together to carry out a specific function. • Groups of organs interact in an organ system. • Organ systems work together to function in an efficient, integrated manner.

Section 1 The Human Body Plan Chapter 45 Major Organ Systems of the Human Body

Section 1 The Human Body Plan Chapter 45 Organs and Organ Systems, continued • Integration of Organ Systems • An even higher level of organization is the integration of organ systems. • The integration of organ systems can be described as each organ system having organs associated with it according to that organ’s primary function. This is so the organ system can work more efficiently.

Section 1 The Human Body Plan Chapter 45 Overview of Organ Systems Click below to watch the Visual Concept. Visual Concept

Section 1 The Human Body Plan Chapter 45 Body Cavities • Many organs and organ systems in the human body are housed in compartments called body cavities. • These cavities protect internal organs from injuries and permit organs to function while remaining securely supported. • Each human cavity can contains one or more organs.

Section 1 The Human Body Plan Chapter 45 Body Cavities, continued • The human body has five main body cavities, including the cranial cavity, the spinal cavity, the thoracic cavity, the abdominal cavity, and the pelvic cavity. • The cranial cavity is the cavity that contains, supports, and protects the brain. • The spinal cavity is the cavity that contains, supports, and protects the spinal cord.

Section 1 The Human Body Plan Chapter 45 Body Cavities, continued • The thoracic cavity is the cavity that contains, supports, and protects the heart, esophagus, and the organs of the respiratory system. • The abdominal cavity is the cavity that contains, supports, and protects the digestive system. • The pelvic cavity is the cavity that contains, supports, and protects the organs of the reproductive and excretory systems.

Section 1 The Human Body Plan Chapter 45 Cavities of the Human Body

Section 1 The Human Body Plan Chapter 45 Human Body Cavities Click below to watch the Visual Concept. Visual Concept

Section 2 Skeletal System Chapter 45 Objectives • Distinguishbetween the axial skeleton and the appendicular skeleton. • Explainthe function and structure of bones. • Summarizehow bones develop and elongate. • Listthree types of joints and give an example of each. • Describea common disorder that affects the skeleton.

Section 2 Skeletal System Chapter 45 The Skeleton • A skeleton is the bones of a human or animal body that form the framework of the body, support the muscles and organs, and protect the inner organs. • The variation in size and shape among the bones that make up the skeleton reflects their different roles in the body.

Section 2 Skeletal System Chapter 45 Human Skeleton

Section 2 Skeletal System Chapter 45 The Skeleton, continued • The human skeleton is composed of two parts—the axial skeleton and the appendicular skeleton. • The bones of the arms and legs, along with the scapula, clavicle, and pelvis, make up the appendicular skeleton. • The bones of the skull, ribs, spine, and sternum form the axial skeleton.

Section 2 Skeletal System Chapter 45 Anatomy of a Human Skeletal System Click below to watch the Visual Concept. Visual Concept

Section 2 Skeletal System Chapter 45 Bone Function and Structure • The bones that make up the skeleton function in a variety of ways, such as supporting the muscles, protecting internal organs, helping movement, and playing vital roles in important metabolic processes. • Bones do not make up most of a body’s mass.

Section 2 Skeletal System Chapter 45 Bone Function and Structure, continued • Long Bone Structure • A long bone’s surface is covered by a tough membrane called the periosteum. • Periosteum is a white, double layered membrane that covers the entire surface of bone except for the joint surfaces and is richly supplied with nerve fibers and blood vessels.

Section 2 Skeletal System Chapter 45 Bone Function and Structure, continued • Long Bone Structure, continued • Under the periosteum is a hard material called compact bone, and this part of the bone gives all bones their strength and rigidity. • Compact bone is composed of cylinders made of mineral crystals and protein fibers called lamellae.

Section 2 Skeletal System Chapter 45 Bone Function and Structure, continued • Long Bone Structure, continued • Each lamellae is made up of a narrow channel called a Haversian canal, which contains the blood vessels in compact bone. • Surrounding each Haversian canal are protein fibers and osteocytes. • Osteocytes are a specific type of bone cell.

Section 2 Skeletal System Chapter 45 Bone Function and Structure, continued • Long Bone Structure, continued • Beneath some compact bone is a network of connective tissue called spongy bone. • Spongy bone is less dense bone tissue that has many open spaces.

Section 2 Skeletal System Chapter 45 Structure of Bone

Section 2 Skeletal System Chapter 45 Bone Function and Structure, continued • Bone Marrow • Bone marrow is a soft tissue inside some bones that can be either red or yellow. • The type of bone marrow present determines both its composition and function.

Section 2 Skeletal System Chapter 45 Parts of a Human Bone - 1 & 2 Click below to watch the Visual Concept. Visual Concept

Section 2 Skeletal System Chapter 45 Bone Function and Structure, continued • Injury and Repair • Despite their strength, bones will crack or even break if they are subjected to certain situations or are overused. • A crack or break is referred to as a fracture. • A fracture is an injury in which the tissue of a bone is broken.

Section 2 Skeletal System Chapter 45 Bone Development • During fetal development, some bones that were originally cartilage will slowly be replaced by actual bone. This process is called ossification.

Section 2 Skeletal System Chapter 45 Bone Development, continued • Bone Elongation • Bones continue to grow after a person’s birth. • Bone elongation and growth take place near the ends of long bones in an area known as the epiphyseal plate. • The epiphyseal plate is found at the joint ends of long bones and is composed of cartilage. This area of bone will eventually become mature bone.

Section 2 Skeletal System Chapter 45 Human Bone Growth Click below to watch the Visual Concept. Visual Concept

Section 2 Skeletal System Chapter 45 Joints • The place where two bones meet is known as a joint. • Three major kinds of joints are found in the human body—fixed, semimovable, and movable. • Fixed Joints • A fixed joint is a joint at which no movement occurs.

Section 2 Skeletal System Chapter 45 Joints, continued • Semimovable Joints • A semimovable joint is one that will permit limited movement. • Cartilage can be involved to help these joints move.

Section 2 Skeletal System Chapter 45 Joints, continued • Movable Joints • A movable joint is a joint at which a wide range of motion occurs. • There are different types of movable joints, including hinge, ball-and-socket, pivot, saddle, and gliding. • A hinge joint allows limited movement in only one plane.

Section 2 Skeletal System Chapter 45 Joints, continued • Movable Joints, continued • A ball-and-socket joint is another type of moveable joint and allows 360 degree movement in 2 planes. • A pivot joint allows 180 degree movement in only one plane. • A saddle joint will allow 360 degree movement in only one plane. • A gliding joint allows bones to slide over one another.

Section 2 Skeletal System Chapter 45 Joints, continued • Joint Structure • Joint structure helps movable joints deal with the pressure and stress of everyday life. • Joints are covered with cartilage and secrete synovial fluid to reduce friction. Joints are also connected with ligaments to aid in joint movement. • Even with all this protection a joint can still be injured.

Section 2 Skeletal System Chapter 45 Joints, continued • Joint Structure, continued • The term arthritis is used to describe disorders that cause painful, swollen joints. • Rheumatoid arthritis develops when the immune system begins to attack body tissues, and joints become stiff and deformed. • Osteoarthritis is a degenerative joint disease in which the cartilage covering the surface of bone becomes thinner and rougher.

Section 2 Skeletal System Chapter 45 Types of Joints

Section 2 Skeletal System Chapter 45 Types of Joints Click below to watch the Visual Concept. Visual Concept

Section 3 Muscular System Chapter 45 Objectives • Distinguishbetween the three types of muscle tissues. • Describethe structure of skeletal muscle fibers. • Explainhow skeletal muscles contract. • Describehow muscles move bones. • Explainthe process in which a muscle becomes fatigued.

Section 3 Muscular System Chapter 45 Muscle Types • A muscle is an organ that can contract in a coordinated fashion and includes muscle tissue, blood vessels, nerves, and connective tissue. • Their ability to contract and relax not only enables the body to move, but also provides the force that pushes substances, such as blood and food, through the body. • The human body has three types of muscle tissues: skeletal, smooth, and cardiac.

Section 3 Muscular System Chapter 45 Muscle Types, continued • Skeletal muscles consciously control the moving parts of the body and are often referred to as voluntary muscles. • Skeletal muscles are made up of muscle fibers. • Muscle fibers consist of multinucleated elongated cells with light and dark stripes. These stripes are called striations.

Section 3 Muscular System Chapter 45 Muscle Types, continued • Muscle fibers are grouped into bundles called fascicles. • Groups of fascicles are bound together by connective tissue to form a muscle. • The connective tissue in skeletal muscle cells can unite to form tendons.

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