Skin - Anatomy and Physiology PDF
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This document provides an overview of skin structure and function, including the epidermis, dermis, and hypodermis. It discusses cell types, layers, and various functions of the skin, such as protection, sensation, excretion, and thermoregulation. It also covers skin color, hair, and nails.
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Skin Chapter 10 Copyright © 2019, Elsevier Inc. All Rights Reserved. Learning Objectives Lesson 10.1: Overview of the Dermis and Epidermis 1. Define the terms integument and integumentary system. 2. Describe the structure of the skin. 3. Describe the ce...
Skin Chapter 10 Copyright © 2019, Elsevier Inc. All Rights Reserved. Learning Objectives Lesson 10.1: Overview of the Dermis and Epidermis 1. Define the terms integument and integumentary system. 2. Describe the structure of the skin. 3. Describe the cell types and cell layers of the epidermis in thick skin and give the function of each. 4. Discuss epidermal growth and repair 5. Describe structural components, and functions of the dermis. Copyright © 2019, Elsevier Inc. All Rights Reserved. Structure of the Skin Skin (integument) is the body’s largest organ Skin classified as the cutaneous membrane Two primary layers Epidermis – the superficial, thinner layer Dermis – the deep, thicker layer Hypodermis lies beneath the dermis Thin and thick skin “Thin skin” has hair and a smooth surface “Thick skin” has no hair and a ridged Copyright © 2019, Elsevier Inc. All Rights Reserved. The Skin (Drawing): Barbara Cousins. (Photo): Ed Reschke. Copyright © 2019, Elsevier Inc. All Rights Reserved. Copyright © 2019, Elsevier Inc. All Rights Reserved. Thick Skin Copyright © 2019, Elsevier Inc. All Rights Reserved. Thin Skin Copyright © 2019, Elsevier Inc. All Rights Reserved. Thick and Thin Skin Copyright Kevin Patton, Lion Den Inc, Weldon Spring, MO. Copyright © 2019, Elsevier Inc. All Rights Reserved. Cell Types in the Epidermis Keratinocytes: Sometimes called corneocytes after they are fully keratinized Melanocytes: Contribute to skin color and filter ultraviolet light Epidermal dendritic cells: Play a role in immune response; also called Langerhans cells Tactile epithelial cells (Merkel cells): Attach to sensory nerve endings to form “light touch” receptors Copyright © 2019, Elsevier Inc. All Rights Reserved. The Epidermis Copyright © 2019, Elsevier Inc. All Rights Reserved. Cell Layers of the Epidermis (Slide 1 of 2) Up to 5 layers (strata) Stratum basale (base layer): Single layer of columnar cells Stratum spinosum (spiny layer): Cells arranged in 8 to 10 layers with desmosomes that pull cells into spiny shapes; start producing keratin Stratum granulosum (granular layer): Cells arranged in 2 to 4 layers and filled with keratohyalin granules (needed for keratin formation) leak proof Copyright © 2019, Elsevier Inc. All Rights Reserved. Cell Layers of the Epidermis (Slide 2 of 2) Stratum lucidum (clear layer): Cells filled with a keratin precursor called eleidin; absent in thin skin. Dying cells. Stratum corneum (horny layer): Most superficial layer; dead cells filled with keratin (barrier area) first line of defence Copyright © 2019, Elsevier Inc. All Rights Reserved. Copyright © 2019, Elsevier Inc. All Rights Reserved. Epidermal Growth and Repair Turnover or regeneration time: The time required for epidermal cells to form in the stratum basale and migrate to the skin surface—about 35 days Normally 10% to 12% of all cells in the stratum basale enter mitosis daily Copyright © 2019, Elsevier Inc. All Rights Reserved. Dermis Sometimes called “true skin” Lies beneath and is much thicker than the epidermis Gives strength to the skin Serves as a reservoir storage area for water and electrolytes Rich vascular supply (blood flow) Copyright © 2019, Elsevier Inc. All Rights Reserved. Arrector Pili Muscles Copyright © 2019, Elsevier Inc. All Rights Reserved. Dermal Growth and Repair Unlike the epidermis, the dermis does not continually shed and regenerate itself During wound healing, fibroblasts begin forming an unusually dense mass of new connective fibers (scar tissue- does not strech) Cleavage lines (also called Langer lines) Copyright © 2019, Elsevier Inc. All Rights Reserved. Cleavage Lines Copyright © 2019, Elsevier Inc. All Rights Reserved. Learning Objectives Lesson 10.2: Functions of the Skin 6. Discuss the composition and function of the hypodermis. 7. Discuss factors that influence skin color. 8. Discuss functions of the skin, including the composition and skin surface film. 9. Explain how the skin functions in the homeostasis of body temperature. 10. Describe the formation, structure, and growth of hair and nails. 11. Discuss and compare the structure and function of sweat (sudoriferous), sebaceous, and ceruminous glands. 12. Discuss various skin disorders, including skin infections, vascular and inflammatory skin disorders, skin cancer, and the classification of burns as first, Copyright © 2019, Elsevier Inc. All Rights Reserved. Hypodermis Also called the subcutaneous layer or superficial fascia Located deep to the dermis; forms a connection between skin and other structures Not part of the skin Made up of mostly loose fibrous and adipose tissue, along with nerves, blood vessels and lymphatic vessels. Copyright © 2019, Elsevier Inc. All Rights Reserved. Skin Colour: Melanin (Slide 1 of 2) Basic determinant of colour is quantity, type, and distribution of melanin Types of melanin include: Eumelanin– dark brown / almost black Pheomelanin– reddish orange Prolonged exposure to the UV radiation in sunlight causes melanocytes to increase melanin production and darken skin colour Copyright © 2019, Elsevier Inc. All Rights Reserved. Other Pigments Hemoglobin: Color changes also occur as a result of changes in blood flow Redder skin color when blood flow to skin increases Cyanosis: Bluish color caused by darkening of hemoglobin when it loses oxygen and gains carbon dioxide Other pigments: From cosmetics, tattoos, bile pigments in jaundice Copyright © 2019, Elsevier Inc. All Rights Reserved. Cyanosis From Epstein O, Perkin GD, Cookson J, de Bono D: Clinical examination, ed 3, St Louis, 2003, Mosby. Copyright © 2019, Elsevier Inc. All Rights Reserved. Skin Discoloration Gradient from McCance K, Huether S: Pathophysiology, ed 5, St. Louis, 2005, Mosby Copyright © 2019, Elsevier Inc. All Rights Reserved. Functions of the Skin Protection Physical barrier to microorganisms Barrier to chemical hazards Reduces potential for mechanical trauma Protects against excess UV exposure (melanin function) See Table 10-2 Copyright © 2019, Elsevier Inc. All Rights Reserved. Surface Film on the Skin Shedding of epithelial elements is called desquamation Functions Antibacterial, antifungal activity Lubrication Hydration of skin surface Buffer of caustic irritants Blockade of toxic agents Copyright © 2019, Elsevier Inc. All Rights Reserved. Functions of the Skin Sensation Sensory receptors detect stimuli that permit us to detect pressure, touch, temperature, pain, and other general senses Flexibility Skin is supple and elastic, permitting change in body contours without injury Excretion Water Urea, ammonia, uric acid Copyright © 2019, Elsevier Inc. All Rights Reserved. Hormone (Vitamin D) Production Exposure of skin to UV light converts 7- dehydrocholesterol to cholecalciferol, a precursor to vitamin D Blood transports the precursor to the liver and kidneys, where vitamin D is produced The process and the end result fulfill the steps required for vitamin D to be classified as a hormone Copyright © 2019, Elsevier Inc. All Rights Reserved. Vitamin D Production Copyright © 2019, Elsevier Inc. All Rights Reserved. Functions of the Skin Immunity Phagocytic cells destroy bacteria Homeostasis of body temperature Heat production must equal heat loss; skin plays a critical role in this process Copyright © 2019, Elsevier Inc. All Rights Reserved. Homeostasis of Body Temperature Heat production Chief determinant: Amount of muscular work being performed Heat loss Evaporation: To evaporate any fluid, heat energy must be expended Copyright © 2019, Elsevier Inc. All Rights Reserved. Heat Loss Radiation: Transfer of heat from one object to another without actual contact Conduction: Transfer of heat to any substance actually in contact with the body Convection: Transfer of heat away from a surface by movement of air Copyright © 2019, Elsevier Inc. All Rights Reserved. Mechanisms of Heat Loss From Patton KT, Thibodeau G: Human body in health & disease, ed 7, St. Louis, 2018, Mosby. Copyright © 2019, Elsevier Inc. All Rights Reserved. Homeostatic Regulation of Heat Loss Heat loss by the skin is controlled by a negative feedback loop Receptors in the hypothalamus monitor the body’s internal temperature If body temperature is increased, the hypothalamus sends a nervous signal to the sweat glands and blood vessels of the skin Copyright © 2019, Elsevier Inc. All Rights Reserved. Role of the Skin in Homeostasis of Body Temperature Copyright © 2019, Elsevier Inc. All Rights Reserved. Development of Hair Distribution: Over entire body except palms of hands and soles of feet and a few other small areas Lanugo: Fine, soft hair coat that exists before birth Terminal hair: Coarse pubic and axillary hair that develops at puberty Hair follicles and hair develop from epidermis Copyright © 2019, Elsevier Inc. All Rights Reserved. Hair Follicle C: Copyright © by David Scharf, 1986, 1993. Copyright © 2019, Elsevier Inc. All Rights Reserved. Development of Hair Papilla- base of hair follicle Root Shaft- visible above skin Medulla- inner part of hair shaft Cortex- outer…. Germinal Matrix--- group of cells at the bottom of follicle Copyright © 2019, Elsevier Inc. All Rights Reserved. Appearance of Hair Color: Result of different amounts, distribution, and types of melanin in the cortex of hair Growth: Hair growth and rest periods alternate Sebaceous glands: Attach to and secrete sebum (skin oil) into each hair follicle Male pattern baldness (androgenic alopecia): Results from a combination of genetic tendency and male sex hormones Copyright © 2019, Elsevier Inc. All Rights Reserved. Nails Consist of epidermal cells converted to hard keratin Nail body: Visible part of each nail Root: Part of the nail in groove hidden by a fold of skin (the cuticle) Lunula: Moon-shaped white area nearest root Copyright © 2019, Elsevier Inc. All Rights Reserved. Structure of Nails Courtesy Christine Olekyk. Copyright © 2019, Elsevier Inc. All Rights Reserved. Nail Bed Appears pink under translucent nails Nails may have pigmented streaks Growth: Nails grow by mitosis of cells in the stratum basale beneath the lunula Artificial nails worn by health care workers is discouraged Copyright © 2019, Elsevier Inc. All Rights Reserved. Sweat Glands Eccrine Glands – subcutaneous layer Most numerous sweat glands; quite small Distributed over the total body surface except for a few small areas Function throughout life Secrete perspiration (sweat) Transparent watery liquid rich in salts etc Copyright © 2019, Elsevier Inc. All Rights Reserved. Skin Glands Copyright © 2019, Elsevier Inc. All Rights Reserved. Apocrine Glands Located deep in subcutaneous layer Limited distribution Axilla Areola of breast Around anus Large (often more than 5 mm in diameter) Begin to function at puberty Secretion shows cyclic changes in female with menstrual cycle Copyright © 2019, Elsevier Inc. All Rights Reserved. Sebaceous Glands Secrete sebum (oil) Lipid components have antifungal activity Simple, branched glands Found in dermis except in palms and soles Secretion increases in adolescence Copyright © 2019, Elsevier Inc. All Rights Reserved. Ceruminous Glands Modified apocrine sweat glands Empty contents into external ear canal alone or with sebaceous glands Cerumen protects area from dehydration AKA ear wax Copyright © 2019, Elsevier Inc. All Rights Reserved. Cycle of Life: Skin Children Skin is smooth, unwrinkled, and characterized by elasticity and flexibility Few sweat glands Rapid healing Adults Development and activation of sebaceous and sweat glands Increased sebum production; can result in acne Old age Decreased sebaceous and sweat gland activity Wrinkling Decline in body’s ability to cool itself Copyright © 2019, Elsevier Inc. All Rights Reserved. The Big Picture: Skin and the Whole Body Skin is a major component of the body’s structural framework Skin defines the internal environment of the body Primary functions: Support and protection Copyright © 2019, Elsevier Inc. All Rights Reserved. Skeletal Tissues Chapter 11 Copyright © 2019, Elsevier Inc. All Rights Reserved. Learning Objectives Lesson 11.1: Bone Types and Functions (Slide 1 of 2) 1. List and discuss the five homeostatic functions of bones. 2. List the four types of bones and give examples of each. 3. Identify the six major structures of a typical long bone and the parts of flat bone. 4. Identify each of the major constituents of bone as a tissue and discuss how structural organization contributes to function. 5. Identify by name and discuss each of the major components of a haversian system. 6. Compare and contrast cancellous bone and compact bone. 7. List and describe the functions of the three major types of cells found in bones. Copyright © 2019, Elsevier Inc. All Rights Reserved. Functions of Bone Support: Ligaments help hold bones together Protection Movement Mineral storage Hematopoiesis– blood formation (long bones) Copyright © 2019, Elsevier Inc. All Rights Reserved. The Skeleton Copyright © 2019, Elsevier Inc. All Rights Reserved. Five Types of Bones Long bones Short bones Flat bones Irregular bones Sesamoid bones-appears seed like Copyright © 2019, Elsevier Inc. All Rights Reserved. Types of Bones (Slide 1 of 2) Copyright © 2019, Elsevier Inc. All Rights Reserved. Types of Bones (Slide 2 of 2) Bones vary in their proportions of two types of bone tissue Compact bone Cancellous (spongy) bone Copyright © 2019, Elsevier Inc. All Rights Reserved. Parts of a Long Bone (Slide 1 of 4) Diaphysis Main shaft of a long bone Hollow, cylindrical shape and thick compact bone Epiphyses Both ends of a long bone; made of cancellous bone filled with red marrow Bulbous shape Copyright © 2019, Elsevier Inc. All Rights Reserved. Parts of a Long Bone (Slide 2 of 4) B: From White T: Human osteology, ed 2, Philadelphia, 2000, Academic Press. Copyright © 2019, Elsevier Inc. All Rights Reserved. Parts of a Long Bone (Slide 3 of 4) Articular cartilage Layer of hyaline cartilage that covers the articular surface of epiphyses Periosteum Dense, white fibrous membrane that covers bone Contains cells that form and destroy bone Contains blood vessels that send branches into bone Copyright © 2019, Elsevier Inc. All Rights Reserved. Parts of a Long Bone (Slide 4 of 4) Medullary cavity Tubelike, hollow space in the diaphysis of a long bone In adults, filled with a connective tissue rich in fat (yellow marrow) Endosteum Membrane that line the medullary cavity Copyright © 2019, Elsevier Inc. All Rights Reserved. Parts of a Flat Bone (Slide 1 of 2) Inner portion is cancellous (spongy) bone covered on the outside with compact bone Cranial flat bones have an internal table and an external table of compact bone Like long bones, flat bones are covered with periosteum and lined with endosteum Other flat bones, short bones, and irregular bones have features similar to the cranial bones Copyright © 2019, Elsevier Inc. All Rights Reserved. Parts of a Flat Bone (Slide 2 of 2) B: From Moses K, Nava P, Banks J, Petersen D: Moses atlas of clinical gross anatomy, Philadelphia, 2005, Mosby. Copyright © 2019, Elsevier Inc. All Rights Reserved. Bone Tissue Extracellular components are hard and calcified (hard). Rigidity of bone allows it to perform its supportive and protective functions Tensile strength of bone tissue is nearly equal to that of cast iron, at less than ⅓ the weight Copyright © 2019, Elsevier Inc. All Rights Reserved. Microscopic Structure of Compact Bone Contains many cylinder-shaped structural units, called osteons or haversian systems Osteons surround central (osteonal or haversian) canals that run lengthwise through bone and are connected by transverse canals (Volkmann canals) Copyright © 2019, Elsevier Inc. All Rights Reserved. Copyright © 2019, Elsevier Inc. All Rights Reserved. Microscopic Structure of Bone B: Dennis Strete. Copyright © 2019, Elsevier Inc. All Rights Reserved. Microscopic Structure of Cancellous Bone Nutrients are delivered and waste products removed by diffusion through tiny canaliculi No osteons A lattice of bony branches (trabeculae) is arranged along lines of stress to enhance the bone’s strength Copyright © 2019, Elsevier Inc. All Rights Reserved. Microscopic Structure of Bone Copyright © 2019, Elsevier Inc. All Rights Reserved. Microscopic Structure of Cancellous Bone Blood supply Bone cells receive blood supply from the bone marrow in the internal medullary cavity of cancellous bone Blood vessels from the periosteum become incorporated into the bone and serve the nutrient needs of cells by way of transverse (Volkmann) canals, connected with vessels in the central canals of osteons Copyright © 2019, Elsevier Inc. All Rights Reserved. Types of Bone Cells Osteoblasts (BUILD) Small cells that synthesize and secrete osteoid Collagen fibrils line up in osteoid and serve as a framework for the deposition of calcium and phosphate Osteoclasts Giant, multinucleated cells Erode bone Allows for release of minerals Osteocytes (MAINTAIN) help structure Mature, non dividing osteoblasts surrounded by bone matrix Copyright © 2019, Elsevier Inc. All Rights Reserved. Bone-Forming and Bone-Eroding Cells From Williams P: Gray’s anatomy, ed 38, Philadelphia, 1996, Churchill Livingstone. Copyright © 2019, Elsevier Inc. All Rights Reserved. Learning Objectives Lesson 11.2: Bone Marrow, Cartilage, and Fracture Repair (Slide 1 of 2) 8. Discuss the two types of bone marrow. 9. Identify the three specialized types of cartilage, give examples of each, and summarize the structural and functional differences among them. 10. Explain the role bones play in maintaining homeostasis of blood calcium levels in the body. 11. Compare and contrast the development of intramembranous and endochondral bone. 12. Describe the process of bone remodeling and the steps involved in bone fracture repair. Copyright © 2019, Elsevier Inc. All Rights Reserved. Bone Marrow (Slide 1 of 3) Type of soft, diffuse connective tissue; called myeloid tissue Two types of marrow develop during a person’s lifetime Red marrow- found in all bones Functions to produce red blood cells Yellow marrow– red changes to yellow at old age Marrow cells that become saturated with fat and are no longer active in blood cell production Main bones in an adult that still contain red marrow include the ribs, bodies of the vertebrae, humerus, pelvis, and femur Copyright © 2019, Elsevier Inc. All Rights Reserved. Bone Marrow (Slide 2 of 3) Wikimedia Common. Copyright © 2019, Elsevier Inc. All Rights Reserved. Structure of Cartilage Cartilage resembles bone in some ways Cartilage has the flexibility of a firm plastic material, whereas bone has the rigidity of cast iron Cartilage is an excellent skeletal support tissue in the developing embryo No canal system and no blood vessels penetrate the matrix Avascular! Copyright © 2019, Elsevier Inc. All Rights Reserved. Types of Cartilage (Slide 1 of 2) Hyaline cartilage (2) Most common Forms the costal cartilages that connect anterior ends of ribs with sternum, rings in the trachea, bronchi and tip of the nose Elastic cartilage. (1) Form to the external ear, epiglottis that covers opening of the respiratory tract during swallowing, and eustachian tubes Fibrocartilage (3) Characterized by abundant fibrous elements within the matrix Intervertebral disks Copyright © 2019, Elsevier Inc. All Rights Reserved. Functions of Cartilage Sustains great weight when covering the articulating surfaces of bones Shock-absorbing pad between articulating bones in the spine Provides strong yet pliable support structure in the external ear, nose, and respiratory passages Copyright © 2019, Elsevier Inc. All Rights Reserved. Endochondral Ossification Most bones begin as a cartilage model, with bone formation spreading essentially from the center to the ends Periosteum develops and enlarges to produce a collar of bone Secondary ossification centers appear in the epiphysis, and bone growth proceeds toward the diaphysis The epiphyseal plate remains between the diaphysis and each epiphysis until bone growth in length is complete Copyright © 2019, Elsevier Inc. All Rights Reserved. Endochondral Bone Formation (Slide 1 of 2) From Patton KT, Thibodeau G: Human body in health & disease, ed 7, St. Louis, 2018, Mosby. Copyright © 2019, Elsevier Inc. All Rights Reserved. Endochondral Bone Formation (Slide 2 of 2) From Patton KT, Thibodeau G: Human body in health & disease, ed 7, St. Louis, 2018, Mosby. Copyright © 2019, Elsevier Inc. All Rights Reserved. Endochondral Ossification of the Hand and Wrist Ed Reschke. Copyright © 2019, Elsevier Inc. All Rights Reserved. Epiphyseal Plate Epiphyseal plate is composed of four layers “Resting” cartilage cells Zone of proliferation Zone of hypertrophy Zone of calcification Copyright © 2019, Elsevier Inc. All Rights Reserved. Epiphyseal Plate Structure Copyright © 2019, Elsevier Inc. All Rights Reserved. Growth of the Epiphyseal Plate From Booher JM, Thibodeau Ga: Athletic injury assessment, St. Louis, 1985, Mosby. Copyright © 2019, Elsevier Inc. All Rights Reserved. Epiphyseal Plate When epiphyseal cartilage cells stop multiplying and the cartilage has become completely ossified, bone growth ends The epiphyseal plate can be a site of bone fractures in young people Long bones grow in both length and diameter Copyright © 2019, Elsevier Inc. All Rights Reserved. Epiphyseal Fracture Copyright © 2019, Elsevier Inc. All Rights Reserved. Fracture and Fracture Healing Fracture tears and destroys blood vessels that carry nutrients to osteocytes Vascular damage initiates repair sequence Osteoblasts form callus tissue (bind two ends together) Fracture hematoma Copyright © 2019, Elsevier Inc. All Rights Reserved. Fracture Healing Copyright © 2019, Elsevier Inc. All Rights Reserved. Cycle of Life: Skeletal Tissues Skeleton is fully ossified by mid-20s Adults: Changes occur as a result of specific conditions Decreased density and strength result from pregnancy, nutritional deficiencies, and illness Advanced adulthood: Apparent degeneration Exercise can counteract degeneration Copyright © 2019, Elsevier Inc. All Rights Reserved. Axial Skeleton Chapter 12 Copyright © 2019, Elsevier Inc. All Rights Reserved. Learning Objectives Lesson 12.1: Components of the Axial Skeleton: Skull 1. Identify the two main subdivisions of the skeleton and the primary subdivisions of the axial skeleton. 2. Do the following regarding the bones of the skull: Distinguish between the bones of the skull and those of the face. List the sutures and fontanels of the skull. Discuss the clinical significance of the cribriform plate of the ethmoid bone. Copyright © 2019, Elsevier Inc. All Rights Reserved. Introduction Skeletal tissues form bones, which are the organs of the skeletal system The relationship of bones to one another and to other body structures provides a basis for understanding the function of other organ systems The adult skeleton is composed of 206 separate bones Copyright © 2019, Elsevier Inc. All Rights Reserved. Divisions of the Skeleton Axial skeleton Appendicular skeleton Copyright © 2019, Elsevier Inc. All Rights Reserved. Anterior View of the Skeleton Copyright © 2019, Elsevier Inc. All Rights Reserved. Posterior View of the Skeleton Copyright © 2019, Elsevier Inc. All Rights Reserved. Lateral View of the Skeleton Copyright © 2019, Elsevier Inc. All Rights Reserved. The Skull: Cranial Bones Frontal bone Contains the frontal sinuses Forms the upper portion of the orbits Forms the coronal suture with the two parietal bones Copyright © 2019, Elsevier Inc. All Rights Reserved. Anterior View of the Skull Copyright © 2019, Elsevier Inc. All Rights Reserved. Right Side View of the Skull (Slide 1 of 2) Copyright © 2019, Elsevier Inc. All Rights Reserved. Floor of the Cranial Cavity Viewed From Above (Slide 1 of 2) Copyright © 2019, Elsevier Inc. All Rights Reserved. Orbital Bones Copyright © 2019, Elsevier Inc. All Rights Reserved. Parietal and Temporal Bones Copyright © 2019, Elsevier Inc. All Rights Reserved. Frontal and Occipital Bones Copyright © 2019, Elsevier Inc. All Rights Reserved. Sphenoid Bone Copyright © 2019, Elsevier Inc. All Rights Reserved. Ethmoid Bone Copyright © 2019, Elsevier Inc. All Rights Reserved. Right Maxilla Copyright © 2019, Elsevier Inc. All Rights Reserved. Zygomatic and Palatine Bones Copyright © 2019, Elsevier Inc. All Rights Reserved. Right Lacrimal and Right Nasal Bones Copyright © 2019, Elsevier Inc. All Rights Reserved. Skull: Cranial Bones Parietal bones Form the bulging top of the cranium Form several sutures Temporal bones Copyright © 2019, Elsevier Inc. All Rights Reserved. Skull: Cranial Bones Occipital bone Forms the lower, posterior part of the skull Forms immovable joints with three other cranial bones and a movable joint with the first cervical vertebra Sphenoid bone A bat-shaped bone located in the central portion of the cranial floor Forms part of the lateral wall of the cranium and part of the floor of each orbit Contains the sphenoid sinuses Copyright © 2019, Elsevier Inc. All Rights Reserved. Skull: Cranial Bones Ethmoid bone Forms the anterior cranial floor, medial orbit walls, upper parts of the nasal septum, and sidewalls of the nasal cavity Copyright © 2019, Elsevier Inc. All Rights Reserved. Skull: Facial Bones Maxilla (upper jaw) Two maxillae form the keystone of the face Articulate with each other and with the nasal, zygomatic, inferior conchae, and palatine bones Form parts of the orbital floor, roof of the mouth, and floor and sidewalls of the nose Each contains a maxillary sinus Copyright © 2019, Elsevier Inc. All Rights Reserved. Skull: Facial Bones Mandible (lower jaw) Forms the only movable joint of the skull with the temporal bone Zygomatic bone Shapes the cheek and forms the outer margin of the orbit Forms the zygomatic arch with the zygomatic process of the temporal bones Nasal bones These two bones form the upper part of the bridge of the nose; cartilage forms the lower part Copyright © 2019, Elsevier Inc. All Rights Reserved. Right and Left Eye Orbits Orbital cavities contain the eyes and associated muscles, lacrimal apparatus, and important blood vessels and nerves Copyright © 2019, Elsevier Inc. All Rights Reserved. Fetal Skull Characterized by unique anatomic features not seen in adult skull Fontanels, or “soft spots,” allow the skull to “mold” during birth and also allow rapid growth of the brain Copyright © 2019, Elsevier Inc. All Rights Reserved. Skull at Birth From Williams P: Gray’s anatomy, ed 38, Philadelphia, 1996, Churchill Livingstone. Copyright © 2019, Elsevier Inc. All Rights Reserved. Fetal Skull Permits differential growth or appearance of skull components over time Face forms a relatively smaller proportion of the cranium at birth than in the adult Head at birth is ¼ the total body height; at maturity, it is about ⅛ total body height Paranasal sinuses change in size and placement with skeletal maturity Copyright © 2019, Elsevier Inc. All Rights Reserved. Learning Objectives Lesson 12.2: Axial Skeleton: Hyoid, Vertebrae, Sternum, and Ribs 3. Identify the hyoid bone. 4. Name the regions of the vertebral column and give the number of vertebrae in each segment. 5. Discuss the bony components of the rib cage, or chest. Copyright © 2019, Elsevier Inc. All Rights Reserved. Hyoid Bone (Slide 1 of 2) Suspended from the styloid processes of the temporal bone Only bone in the body that articulates with no other bones Copyright © 2019, Elsevier Inc. All Rights Reserved. Hyoid Bone (Slide 2 of 2) Copyright © 2019, Elsevier Inc. All Rights Reserved. Vertebral Column Forms the flexible longitudinal axis of the skeleton Characteristics of the vertebrae All but the sacrum and coccyx have a vertebral foramen Second cervical vertebra (Axis) has an upward projection, the dens, to allow rotation of the head Seventh cervical vertebra has a long, blunt, spinous process Copyright © 2019, Elsevier Inc. All Rights Reserved. Vertebral Column Photo Inset: From Williams P: Gray’s anatomy, ed 38, Philadelphia, Churchill Livingstone, 1996. Copyright © 2019, Elsevier Inc. All Rights Reserved. Vertebrae (Slide 1 of 5) From Gosling J, Harris P, Whitmore I, Willan P: Human anatomy, ed 4, Philadelphia, 2002, Mosby. Copyright © 2019, Elsevier Inc. All Rights Reserved. Vertebrae (Slide 2 of 5) From Gosling J, Harris P, Whitmore I, Willan P: Human anatomy, ed 4, Philadelphia, 2002, Mosby. Copyright © 2019, Elsevier Inc. All Rights Reserved. Vertebrae (Slide 3 of 5) From Gosling J, Harris P, Whitmore I, Willan P: Human anatomy, ed 4, Philadelphia, 2002, Mosby. Copyright © 2019, Elsevier Inc. All Rights Reserved. Vertebrae (Slide 4 of 5) From Gosling J, Harris P, Whitmore I, Willan P: Human anatomy, ed 4, Philadelphia, 2002, Mosby. Copyright © 2019, Elsevier Inc. All Rights Reserved. Vertebrae (Slide 5 of 5) From Gosling J, Harris P, Whitmore I, Willan P: Human anatomy, ed 4, Philadelphia, 2002, Mosby. Copyright © 2019, Elsevier Inc. All Rights Reserved. Vertebral Column The vertebral column as a whole articulates with the head, ribs, and iliac bones Individual vertebrae articulate with each other in joints between their bodies and between their articular processes Copyright © 2019, Elsevier Inc. All Rights Reserved. Thorax: Sternum Dagger-shaped bone in the middle of the anterior chest wall made up of three parts: Manubrium Body Xiphoid process Copyright © 2019, Elsevier Inc. All Rights Reserved. Thoracic Cage Copyright © 2019, Elsevier Inc. All Rights Reserved. Thorax: Ribs Twelve pairs of ribs, with the vertebral column and sternum, form the thorax Each rib articulates with the body and transverse process of its corresponding thoracic vertebra From its vertebral attachment, each rib curves outward, then forward and downward Copyright © 2019, Elsevier Inc. All Rights Reserved. Articulation of a Rib and Vertebra From Williams P: Gray’s anatomy, ed 38, Philadelphia, Churchill Livingstone, 1996. Copyright © 2019, Elsevier Inc. All Rights Reserved. Thorax: Ribs Rib attachment to the sternum Ribs 1 through 7 join a costal cartilage that attaches to the sternum Each costal cartilage of ribs 8 through 10 attaches to the costal cartilage of the rib above it; therefore, ribs 8 through 10 are indirectly attached to the sternum Ribs 11 and 12 are floating ribs because they do not attach even indirectly to the sternum Copyright © 2019, Elsevier Inc. All Rights Reserved. Appendicular Skeleton Chapter 13 Copyright © 2019, Elsevier Inc. All Rights Reserved. Learning Objectives Lesson 13.1: Appendicular Skeleton (Slide 1 of 2) 1. List the primary subdivisions of the appendicular skeleton. 2. List the bony components of the shoulder. 3. Discuss the structures and functions of the arm, forearm, and hand. 4. List the bony components of the pelvic girdle. 5. Discuss the structures and functions of the thigh and leg. 6. Discuss the structural components and functional significance of the arches of the foot. 7. List the skeletal differences between men and women. 8. Discuss age-related changes in the skeleton Copyright © 2019, Elsevier Inc. All Rights Reserved. Upper Extremity: Shoulder Girdle and Humerus Shoulder girdle Made up of the scapula and clavicle At its distal end, the clavicle articulates with the acromion process of the scapula Humerus The long bone of the upper part of the arm Articulates proximally with the glenoid fossa of the scapula and distally with the radius and ulna Copyright © 2019, Elsevier Inc. All Rights Reserved. Right Scapula (Slide 1 of 2) Copyright © 2019, Elsevier Inc. All Rights Reserved. Right Scapula (Slide 2 of 2) Photo courtesy Vidic B, Suarez FR: Photographic atlas of the human body, St. Louis, 1984, Mosby. Copyright © 2019, Elsevier Inc. All Rights Reserved. Anterior View of the Bones of the Right Arm and Forearm Photo courtesy Vidic B, Suarez FR: Photographic atlas of the human body, St. Louis, 1984, Mosby. Copyright © 2019, Elsevier Inc. All Rights Reserved. Posterior View of the Bones of the Right Arm and Forearm Photo courtesy Vidic B, Suarez FR: Photographic atlas of the human body, St. Louis, 1984, Mosby. Copyright © 2019, Elsevier Inc. All Rights Reserved. Upper Extremity: Carpal and Metacarpal Bones Carpal bones Eight small bones that form the wrist Carpal bones are bound closely and firmly by ligaments and form two rows of four carpals each The joints between the radius and carpal bones allow wrist and hand movements Metacarpal bones The thumb metacarpal forms the most freely movable joint with the carpal bones Heads of the metacarpal bones (the knuckles) articulate with the phalanges Copyright © 2019, Elsevier Inc. All Rights Reserved. Bones of the Right Hand and Wrist (Slide 1 of 2) Photo courtesy Vidic B, Suarez FR: Photographic atlas of the human body, St. Louis, 1984, Mosby. Copyright © 2019, Elsevier Inc. All Rights Reserved. Lower Extremity: Pelvic Girdle The pelvic girdle is made up of the sacrum and the two coxal bones bound tightly by strong ligaments A stable circular base that supports the trunk and attaches the lower extremities to it Each coxal bone is made up of three bones that fuse together Ilium Ischium Pubis Copyright © 2019, Elsevier Inc. All Rights Reserved. Female Pelvis Photo courtesy Vidic B, Suarez FR: Photographic atlas of the human body, St. Louis, 1984, Mosby. Copyright © 2019, Elsevier Inc. All Rights Reserved. Left Coxal (Hip) Bone From Abrahams P, Marks S, Hutchings R: McMinn’s color atlas of human anatomy, ed 5, Philadelphia, 2003, Mosby. Copyright © 2019, Elsevier Inc. All Rights Reserved. Lower Extremity: Femur, Patella, Tibia Femur Patella Tibia Articulates proximally with the femur to form the knee joint Articulates distally with the fibula and talus Copyright © 2019, Elsevier Inc. All Rights Reserved. Leg Bones (Slide 1 of 2) Copyright © 2019, Elsevier Inc. All Rights Reserved. Leg Bones (Slide 2 of 2) Courtesy Vidic B, Suarez FR: Photographic atlas of the human body, St. Louis, 1984, Mosby. Copyright © 2019, Elsevier Inc. All Rights Reserved. Lower Extremity: Fibula and Foot Fibula Articulates with the tibia Foot Structure is similar to that of the hand, with adaptations for supporting weight Foot bones are held together to form spring arches Copyright © 2019, Elsevier Inc. All Rights Reserved. The Right Foot Photo courtesy Vidic B, Suarez FR: Photographic atlas of the human body, St Louis, 1984, Mosby. Copyright © 2019, Elsevier Inc. All Rights Reserved. Arches of the Foot Drawings from Yvonne Wylie Walston. Photo inset from Seidel HM, Ball JW, Dains JE, Benedict GW: Mosby’s guide to physical examination, ed 5, St. Louis, 2003, Mosby. Copyright © 2019, Elsevier Inc. All Rights Reserved. Skeletal Differences Between Men and Women Male pelvis: Deep, funnel-shaped, with a narrow pubic arch Female pelvis: Shallow, broad, and flaring, with a wider pubic arch Copyright © 2019, Elsevier Inc. All Rights Reserved. Male and Female Pelvises Drawings From Patton KT, Thibodeau G: Human body in Photos from Abrahams P, Marks S, Hutchings R: McMinn’s health & disease, ed 7, St. Louis, 2018, Mosby. color atlas of human anatomy, ed 5, Philadelphia, 2003, Copyright © 2019, Elsevier Inc. All Rights Reserved. Mosby. Articulations Chapter 14 Copyright © 2019, Elsevier Inc. All Rights Reserved. Learning Objectives Lesson 14.1: Joint Types, Functions, and Synovial Joints (Slide 1 of 2) 1. Define the term articulation. 2. Compare the classification of joints according to both structure and function. 3. List the types of fibrous joints and cartilaginous joints and give an example of each. 4. Discuss the seven structures that characterize diarthrotic joints and explain the functional significance of bursae. 5. Discuss the structural characteristics of uniaxial, biaxial, and multiaxial diarthroses and give an example of each. 6. Describe locations in the body where synovial joints can be found and the anatomical features of each. Copyright © 2019, Elsevier Inc. All Rights Reserved. Introduction Articulation Joints Movable joints allow complex, highly coordinated, and purposeful movements to be executed Movement betw. Two articulating bones Copyright © 2019, Elsevier Inc. All Rights Reserved. Classification of Joints Structural classification: Joints are named according to whether they are: Fibrous or cartilaginous joints Synovial joints (fluid filled) Functional classification Synarthroses - Immovable Amphiarthroses – slightly movable Diarthroses – freely movable Copyright © 2019, Elsevier Inc. All Rights Reserved. Fibrous Joints (Synarthroses) Syndesmoses: Joints in which ligaments connect two bones Sutures: Found only in the skull; teethlike projections from adjacent bones interlock with each other Gomphoses: Between the root of a tooth and the alveolar process of the mandible or maxilla Copyright © 2019, Elsevier Inc. All Rights Reserved. Fibrous Joints Copyright © 2019, Elsevier Inc. All Rights Reserved. Cartilaginous Joints (Amphiarthroses) Synchondroses: Hyaline cartilage present between articulating bones Symphyses: Joints in which a pad or disk of fibrocartilage connects two bones Copyright © 2019, Elsevier Inc. All Rights Reserved. Cartilaginous Joints Copyright © 2019, Elsevier Inc. All Rights Reserved. Synovial Joints (Diarthroses) Structures of synovial joints Joint capsule Synovial membrane Articular cartilage Joint cavity Menisci (articular disks) (meniscus) Ligaments Bursae Copyright © 2019, Elsevier Inc. All Rights Reserved. Synovial Joints B from Gosling J, Harris P, Whitmore I, Willan P: Human anatomy, ed 4, Philadelphia, 2002, Mosby. Copyright © 2019, Elsevier Inc. All Rights Reserved. Types of Synovial Joints Uniaxial joints Hinge joints- elbow Pivot joints- dens of axis against atlas Biaxial joints Saddle joints - thumb Condyloid (ellipsoidal) joints - finger Multiaxial joints Ball-and-socket (spheroid) joints – shoulder or hip Gliding joints - vertebrae Copyright © 2019, Elsevier Inc. All Rights Reserved. Uniaxial, Biaxial, and Multiaxial Joints Copyright © 2019, Elsevier Inc. All Rights Reserved. Humeroscapular Joint (Slide 1 of 2) Shoulder joint This is the most mobile joint because of the shallowness of the glenoid cavity Glenoid labrum lends depth to the glenoid cavity Structures that strengthen the shoulder joint are ligaments, muscles, tendons, and bursae Copyright © 2019, Elsevier Inc. All Rights Reserved. Humeroscapular Joint (Slide 2 of 2) Copyright © 2019, Elsevier Inc. All Rights Reserved. Elbow Joint (Slide 1 of 3) Humeroradial joint Humeroulnar joint Both components of the elbow joint are surrounded by a single joint capsule and stabilized by collateral ligaments Classic hinge joint Copyright © 2019, Elsevier Inc. All Rights Reserved. Elbow Joint (Slide 2 of 3) From Gosling J, Harris P, Whitmore I, Willan P: Human anatomy, ed 4, Philadelphia, 2002, Mosby. Copyright © 2019, Elsevier Inc. All Rights Reserved. Elbow Joint (Slide 3 of 3) Medial and lateral epicondyles are externally palpable bony landmarks Olecranon bursa is independent of elbow joint space Inflammation is called olecranon bursitis Trauma to nerve results in unpleasant sensations in the fingers and part of the hand supplied by the nerve Copyright © 2019, Elsevier Inc. All Rights Reserved. Proximal and Distal Radioulnar Joints Stabilized by the annular ligament The two joints permit rotation of the forearm Dislocation of the radial head is called a “pulled elbow” Distal radioulnar joint Acts with the proximal radioulnar joint Permits pronation and supination of the forearm Copyright © 2019, Elsevier Inc. All Rights Reserved. Radiocarpal Joints Only the radius articulates directly with the carpal bones distally (scaphoid and lunate) Joints are synovial Scaphoid bone is fractured frequently Portion of the fractured scaphoid may become avascular Copyright © 2019, Elsevier Inc. All Rights Reserved. Joints of the Wrist (Slide 1 of 3) From Gosling J, Harris P, Whitmore I, Willan P: Human anatomy, ed 4, Philadelphia, 2002, Mosby. Copyright © 2019, Elsevier Inc. All Rights Reserved. Joints of the Wrist (Slide 2 of 3) From Gosling J, Harris P, Whitmore I, Willan P: Human anatomy, ed 4, Philadelphia, 2002, Mosby. Copyright © 2019, Elsevier Inc. All Rights Reserved. Joints of the Wrist (Slide 3 of 3) Courtesy Vidic B, Suarez FR: Photographic atlas of the human body, St. Louis, 1984, Mosby. Copyright © 2019, Elsevier Inc. All Rights Reserved. Carpometacarpal Joints Thumb carpometacarpal joint is unique and important functionally Loose-fitting joint capsule Saddle-shaped articular surface Opposition: Movement of great functional significance Copyright © 2019, Elsevier Inc. All Rights Reserved. Metacarpophalangeal and Interphalangeal Joints Metacarpophalangeal joints Capsule surrounding joints is strengthened by collateral ligaments Primary movements are flexion and extension Interphalangeal joints Typical diarthrotic, hinge-type synovial joints Two categories: Proximal interphalangeal (PIP) joints Distal interphalangeal (DIP) joints Copyright © 2019, Elsevier Inc. All Rights Reserved. Joints of the Hand and Fingers From Gosling J, Harris P, Whitmore I, Willan P: Human anatomy, ed 4, Philadelphia, 2002, Mosby. Copyright © 2019, Elsevier Inc. All Rights Reserved. Hip and Knee Joints Hip joint A joint capsule and ligaments contribute to the joint’s stability Knee joint Largest and one of the most complex and most frequently injured joints Tibiofemoral joint is supported by a joint capsule, cartilage, and numerous ligaments and muscle tendons Copyright © 2019, Elsevier Inc. All Rights Reserved. Hip Joint (Slide 1 of 2) B: Courtesy Vidic B, Suarez FR: Photographic atlas of the human body, St. Louis, 1984, Mosby. Copyright © 2019, Elsevier Inc. All Rights Reserved. Hip Joint (Slide 2 of 2) D: Courtesy Vidic B, Suarez FR: Photographic atlas of the human body, St. Louis, 1984, Mosby. Copyright © 2019, Elsevier Inc. All Rights Reserved. Knee Joint (Slide 1 of 3) B: Courtesy Vidic B, Suarez FR: Photographic atlas of the human body, St. Louis, 1984, Mosby. Copyright © 2019, Elsevier Inc. All Rights Reserved. Knee Joint (Slide 2 of 3) D: Courtesy Vidic B, Suarez FR: Photographic atlas of the human body, St. Louis, 1984, Mosby. Copyright © 2019, Elsevier Inc. All Rights Reserved. Knee Joint (Slide 3 of 3) From Gosling J, Harris P, Whitmore I, Willan P: Human anatomy, ed 4, Philadelphia, 2002, Mosby. Copyright © 2019, Elsevier Inc. All Rights Reserved. Ankle Joint Synovial-type hinge joint Articulation between the lower ends of the tibia and fibula and the upper part of the talus Joint is mortise-shaped, or wedge- shaped Internal rotation injury results in the common “sprained ankle” Other ankle ligaments, such as the deltoid ligament, also may be involved in sprain injuries Copyright © 2019, Elsevier Inc. All Rights Reserved. Knee Joint Injury The knee is the largest and most vulnerable joint Subjected to sudden, strong forces during athletic activity Very common athletic injury; for example, when the weight-bearing knee collides with another person from the side Copyright © 2019, Elsevier Inc. All Rights Reserved. Dorsum of the Ankle and Foot Copyright © 2019, Elsevier Inc. All Rights Reserved. Ankle Joint External ankle rotation injuries generally involve bone fractures rather than ligament tears First-degree ankle injury Second-degree ankle injury Third-degree ankle injury Copyright © 2019, Elsevier Inc. All Rights Reserved. Vertebral Joints Vertebrae are connected to one another by several joints, forming a strong, flexible column Bodies of adjacent vertebrae are connected by intervertebral disks and ligaments Intervertebral disks are made up of two parts Annulus fibrosus Nucleus pulposus Copyright © 2019, Elsevier Inc. All Rights Reserved. Vertebrae Showing a Normal Disk Copyright © 2019, Elsevier Inc. All Rights Reserved. Herniated Disk Copyright © 2019, Elsevier Inc. All Rights Reserved. Lumbar Vertebrae and Ligaments Copyright © 2019, Elsevier Inc. All Rights Reserved. Learning Objectives Lesson 14.2: Joint Movements 8. Identify the types of movement at synovial joints and give examples of specific joints where each occurs. 9. Discuss bursitis, joint disorders, noninflammatory and inflammatory joint disease, and treatments for these conditions. Copyright © 2019, Elsevier Inc. All Rights Reserved. Measuring Range of Motion (ROM) of Synovial Joints An ROM assessment is used to determine the extent of a joint injury ROM can be measured actively or passively; the two methods are generally about equal ROM is measured with instrument called a goniometer Copyright © 2019, Elsevier Inc. All Rights Reserved. Measuring Range of Motion Copyright © 2019, Elsevier Inc. All Rights Reserved. Angular Movements of Synovial Joints Flexion Extension and hyperextension Plantar flexion and dorsiflexion Abduction and adduction Copyright © 2019, Elsevier Inc. All Rights Reserved. Movements and ROM of the Neck (Slide 1 of 2) Copyright © 2019, Elsevier Inc. All Rights Reserved. Movements and ROM of the Neck (Slide 2 of 2) Copyright © 2019, Elsevier Inc. All Rights Reserved. Movements of the Jaw Copyright © 2019, Elsevier Inc. All Rights Reserved. Movements and ROM of the Thoracic and Lumbar Spine (Slide 1 of 2) Copyright © 2019, Elsevier Inc. All Rights Reserved. Movements and ROM of the Thoracic and Lumbar Spine (Slide 2 of 2) Copyright © 2019, Elsevier Inc. All Rights Reserved. Movements and ROM of the Shoulder Copyright © 2019, Elsevier Inc. All Rights Reserved. Circular and Gliding Movements at Synovial Joints Circular movements Rotation and circumduction Supination and pronation Gliding movements: Articular surface of one bone moves over the articular surface of another without any angular or circular movement Special movements Inversion and eversion Copyright © 2019, Elsevier Inc. All Rights Reserved. Special Movements of Synovial Joints Protraction and retraction Elevation and depression Copyright © 2019, Elsevier Inc. All Rights Reserved. Movements and ROM of the Elbow Copyright © 2019, Elsevier Inc. All Rights Reserved. Movements and ROM of the Hand and Wrist Copyright © 2019, Elsevier Inc. All Rights Reserved. Movements and ROM of the Hip Copyright © 2019, Elsevier Inc. All Rights Reserved. Movements and ROM of the Foot and Ankle Copyright © 2019, Elsevier Inc. All Rights Reserved. Cycle of Life: Articulations (Slide 1 of 3) Bone development and the sequence of ossification between birth and skeletal maturity affect joints Older adults ROM decreases Changes in gait Copyright © 2019, Elsevier Inc. All Rights Reserved. Cycle of Life: Articulations (Slide 2 of 3) Skeletal diseases manifest as joint problems Abnormal bone growth (“lipping”) Disease conditions can be associated with a specific developmental period Copyright © 2019, Elsevier Inc. All Rights Reserved. Cycle of Life: Articulations (Slide 3 of 3) Hand: “Reason for the upper extremity” Thumb: “Reason for the hand” Mobility of the upper extremity is extensive because of the following: Arrangement of bones in the shoulder girdle, arm, forearm, wrist, and hand Location and method of attachment of muscles to bones Proper functioning of joints Copyright © 2019, Elsevier Inc. All Rights Reserved. Bursitis and Joint Disorders Bursitis is caused by prolonged pressure, repetitive exercise, or trauma Noninflammatory Inflammatory Copyright © 2019, Elsevier Inc. All Rights Reserved. Noninflammatory Joint Disease No signs or symptoms Osteoarthritis Hips and knees involved first NSAIDS can help with the pain Joint dislocation Pain and soft tissue swelling Sprains Copyright © 2019, Elsevier Inc. All Rights Reserved. Inflammatory Joint Disease Rheumatoid arthritis Chronic inflammation of many tissues and organs Juvenile arthritis Rash, high fever, swelling of liver and spleen Gouty arthritis Excess blood levels of uric acid are deposited as sodium urate crystals Deposited in synovial joints and other tissues Copyright © 2019, Elsevier Inc. All Rights Reserved. Axial Muscles Chapter 15 Copyright © 2019, Elsevier Inc. All Rights Reserved. Learning Objectives Lesson 15.1: Axial Muscles (Slide 1 of 2) 1. List the major connective tissue elements and the size, shape, and fiber arrangement of skeletal muscle. 2. Discuss the attachment of muscles. 3. Explain the functional classification of muscles based on movement patterns. 4. Describe how lever systems work and the three classes of levers, providing examples of body movements in each class. 5. Identify six features that may be used to name a muscle. Copyright © 2019, Elsevier Inc. All Rights Reserved. Learning Objectives Lesson 15.1: Axial Muscles (Slide 2 of 2) 6. Identify major axial muscles, their points of attachment, and their function in the following areas: a. Muscles of facial expression b. Muscles of mastication c. Muscles that move the head d. Muscles of the thorax e. Muscles that move the abdominal wall f. Muscles of the back g. Muscles of the pelvic floor Copyright © 2019, Elsevier Inc. All Rights Reserved. Introduction The body has more than 600 skeletal muscles 40% to 50% of our body weight is skeletal muscle Muscles fill in the form and contour of the body Copyright © 2019, Elsevier Inc. All Rights Reserved. Connective Tissue Components Endomysium Perimysium Epimysium Fuse to become a tendon or aponeurosis Copyright © 2019, Elsevier Inc. All Rights Reserved. Structure of an Organ Copyright © 2019, Elsevier Inc. All Rights Reserved. Size, Shape, and Fiber Arrangement Size: Ranges from extremely small to large masses Shape: Variety of shapes, such as broad, narrow, long, tapering, short, blunt, triangular, quadrilateral, irregular, flat sheets, or bulky masses Arrangement: Variety of arrangements, such as parallel to a long axis, converging to a narrow attachment, oblique, pennate, bipennate, or curved Copyright © 2019, Elsevier Inc. All Rights Reserved. Cross-Section of the Arm Copyright © 2019, Elsevier Inc. All Rights Reserved. Muscle Shape and Fiber Arrangement Copyright © 2019, Elsevier Inc. All Rights Reserved. Attachment of Muscles Origin: Point of attachment that does not move when the muscle contracts Insertion: Point of attachment that moves when the muscle contracts Copyright © 2019, Elsevier Inc. All Rights Reserved. Attachments of Skeletal Muscles Adapted from Muscolino J: Kinesiology, St Louis, 2006, Mosby. Copyright © 2019, Elsevier Inc. All Rights Reserved. Muscle Actions (Slide 1 of 2) Most movements are produced by the coordinated action of several muscles Prime mover Agonists Antagonists Synergists Fixator muscles Copyright © 2019, Elsevier Inc. All Rights Reserved. Muscle Actions (Slide 2 of 2) Copyright © 2019, Elsevier Inc. All Rights Reserved. Lever Systems (Slide 1 of 3) A lever system is composed of four parts: Rigid bar (bone) Fulcrum (F) around which the rod moves (joint) Load (L) that is moved Pull (P) that produces movement (muscle contraction) Copyright © 2019, Elsevier Inc. All Rights Reserved. Lever Systems (Slide 2 of 3) First-class levers Fulcrum lies between the pull and the load Not abundant in the human body; serve as levers of stability Second-class levers Load lies between the fulcrum and the joint at which the pull is exerted Presence of these levers in the human body is a controversial issue Copyright © 2019, Elsevier Inc. All Rights Reserved. Lever Classes (Slide 1 of 2) Copyright © 2019, Elsevier Inc. All Rights Reserved. Lever Systems (Slide 3 of 3) Third-class levers Pull is exerted between the fulcrum and load Permit rapid and extensive movement Most common type of lever in the body Copyright © 2019, Elsevier Inc. All Rights Reserved. Lever Classes (Slide 2 of 2) Copyright © 2019, Elsevier Inc. All Rights Reserved. How Muscles Are Named Muscles are named according to one or more of the following features: Location, function, shape Direction of fibers: Named according to fiber orientation Number of heads or divisions Points of attachment: Origin and insertion points Relative size: Small, medium, or large Copyright © 2019, Elsevier Inc. All Rights Reserved. Overview of Body Musculature (Slide 1 of 3) Copyright © 2019, Elsevier Inc. All Rights Reserved. Overview of Body Musculature (Slide 2 of 3) Copyright © 2019, Elsevier Inc. All Rights Reserved. Overview of Body Musculature (Slide 3 of 3) Copyright © 2019, Elsevier Inc. All Rights Reserved. Important Skeletal Muscles Muscles of facial expression Muscles of mastication: Responsible for chewing movements Muscles that move the head Copyright © 2019, Elsevier Inc. All Rights Reserved. Muscles of Facial Expression and Mastication (Slide 1 of 2) Copyright © 2019, Elsevier Inc. All Rights Reserved. Muscles of Facial Expression and Mastication (Slide 2 of 2) Copyright © 2019, Elsevier Inc. All Rights Reserved. Muscles of the Tongue and Pharynx Copyright © 2019, Elsevier Inc. All Rights Reserved. Muscles of the Neck and Back Copyright © 2019, Elsevier Inc. All Rights Reserved. Trunk Muscles Muscles of the thorax Muscles of the abdominal wall Muscles of the back Muscles of the pelvic floor Copyright © 2019, Elsevier Inc. All Rights Reserved. Muscles of the Thorax Copyright © 2019, Elsevier Inc. All Rights Reserved. Muscles of the Trunk and Abdominal Wall Copyright © 2019, Elsevier Inc. All Rights Reserved. Anterior Wall Above the Umbilicus Copyright © 2019, Elsevier Inc. All Rights Reserved. Muscles of the Back Copyright © 2019, Elsevier Inc. All Rights Reserved. Appendicular Muscles Chapter 16 Copyright © 2019, Elsevier Inc. All Rights Reserved. Learning Objectives Lesson 16.1 Appendicular Muscles 1. Identify major appendicular muscles, their points of attachment, and their function in the following areas: a. Muscles acting on the shoulder girdle b. Muscles that move the upper and lower arm c. Muscles that move the wrist, hand, and fingers d. Muscles that move the thigh and leg e. Muscles that move the ankle and foot 2. Define posture and discuss its importance to the body as a whole. Copyright © 2019, Elsevier Inc. All Rights Reserved. Upper Extremity Muscles Muscles acting on the shoulder girdle Located anteriorly (chest) or posteriorly (back and neck) Allow extensive movement, including: Muscles that move the arm Muscles that move the forearm Muscles that move the wrist, hand, and fingers Copyright © 2019, Elsevier Inc. All Rights Reserved. Muscles Acting on the Shoulder Girdle Copyright © 2019, Elsevier Inc. All Rights Reserved. Cross-Sections Through the Upper Extremity (Slide 1 of 2) Copyright © 2019, Elsevier Inc. All Rights Reserved. Muscles Acting on the Forearm (Slide 1 of 3) Copyright © 2019, Elsevier Inc. All Rights Reserved. Muscles of the Forearm (Slide 1 of 2) Copyright © 2019, Elsevier Inc. All Rights Reserved. Muscles of the Forearm (Slide 2 of 2) Copyright © 2019, Elsevier Inc. All Rights Reserved. Intrinsic Muscles of the Hand Copyright © 2019, Elsevier Inc. All Rights Reserved. Lower Extremity Muscles The pelvic girdle and lower extremity function in locomotion and maintenance of stability Muscles that move the thigh and leg Copyright © 2019, Elsevier Inc. All Rights Reserved. Iliopsoas Muscle Copyright © 2019, Elsevier Inc. All Rights Reserved. Cross-Sections Through the Lower Extremity (Slide 1 of 2) Copyright © 2019, Elsevier Inc. All Rights Reserved. Muscles of the Anterior Aspect of the Thigh Copyright © 2019, Elsevier Inc. All Rights Reserved. Copyright © 2019, Elsevier Inc. All Rights Reserved. Cross-Sections Through the Lower Extremity (Slide 2 of 2) Copyright © 2019, Elsevier Inc. All Rights Reserved. Gluteal Muscles Copyright © 2019, Elsevier Inc. All Rights Reserved. Muscles That Move the Ankle and Foot Extrinsic foot muscles in the leg pull on tendons that insert on bones in the ankle and foot; they are responsible for dorsiflexion, plantar flexion, inversion, and eversion Intrinsic foot muscles are located within the foot; they are responsible for flexion, extension, abduction, and adduction of the toes Copyright © 2019, Elsevier Inc. All Rights Reserved. Superficial Muscles of the Leg Copyright © 2019, Elsevier Inc. All Rights Reserved. Posture Maintaining body posture is a major role of muscles “Good posture”: Body alignment that most favors function; it is achieved by keeping the body’s center of gravity over its base and requires the least muscular work to maintain Muscles exert a continual pull on bones in the opposite direction from gravity Copyright © 2019, Elsevier Inc. All Rights Reserved. Muscle Contraction Chapter 17 Copyright © 2019, Elsevier Inc. All Rights Reserved. Learning Objectives Lesson 17.1: Skeletal Muscle Tissue, Cells, Fibers, and Microfilaments 1. List and discuss the three generalized functions of skeletal muscle tissue. 2. Discuss the three characteristics of skeletal muscle cells that allow them to function as they do. 3. List and discuss the structural parts of skeletal muscle fibers that are also found in other types of cells and the structural parts of skeletal muscle fibers that are not found in other cells. 4. Discuss the structure and function of myofilaments. 5. Explain the series of steps in muscle contraction and the sliding-filament theory. 6. Explain the series of steps in muscle relaxation. 7. Identify and explain the energy sources for muscle contraction, including aerobic and anaerobic respiration. 8. Define a motor unit and myography. 9. Describe the following types of skeletal muscle contractions: twitch, treppe, tetanic, and tonic Copyright © 2019, Elsevier Inc. All Rights Reserved. Introduction Muscular system is responsible for moving the framework of the body In addition to movement, muscle tissue performs various other functions Copyright © 2019, Elsevier Inc. All Rights Reserved. General Functions Movement of the body as a whole or movement of its parts Heat production Posture Copyright © 2019, Elsevier Inc. All Rights Reserved. Characteristics of Skeletal Muscle Cells Excitability (irritability): Ability to be stimulated Contractility: Ability to contract, or shorten, and produce body movement Extensibility: Ability to extend, or stretch, thereby allowing muscles to return to their resting length Copyright © 2019, Elsevier Inc. All Rights Reserved. Structure of the Skeletal Muscle MuMuscle cells are called fibers because of their threadlike shape scle cells are called fibers because of their threadlike shape Copyright © 2019, Elsevier Inc. All Rights Reserved. T Tubules Transverse tubules extend across the sarcoplasm at right angles to the long axis of the muscle fiber Membrane has ion pumps that continually transport Ca++ ions inward from the sarcoplasm Allow electrical impulses traveling along the sarcolemma to move deeper into the cell Copyright © 2019, Elsevier Inc. All Rights Reserved. Features of the Skeletal Muscle Cell Copyright © 2019, Elsevier Inc. All Rights Reserved. Overview of the Muscle Cell Myofibrils: Numerous fine fibers packed close together in sarcoplasm Sarcomere Contractile unit of muscle fibers Each myofibril consists of many sarcomeres Copyright © 2019, Elsevier Inc. All Rights Reserved. Myofilaments Each myofibril contains thousands of thick and thin myofilaments Four different kinds of protein molecules make up myofilaments Myosin Makes up almost all the thick filaments Myosin “heads” are known as cross bridges when attached to actin Copyright © 2019, Elsevier Inc. All Rights Reserved. Myofilaments Actin: Globular protein that forms two fibrous strands twisted around each other to form the bulk of the thin filament Tropomyosin: Protein that blocks the active sites on actin molecules Copyright © 2019, Elsevier Inc. All Rights Reserved. Structure of Myofilaments Copyright © 2019, Elsevier Inc. All Rights Reserved. Excitation and Contraction of a Muscle Fiber A skeletal muscle fiber remains at rest until stimulated by a motor neuron Neuromuscular junction: Motor neurons connect to the sarcolemma at the motor endplate Acetylcholine (ACh): The neurotransmitter released into the synaptic cleft that diffuses across the gap, stimulates the receptors, and initiates an impulse in the sarcolemma Copyright © 2019, Elsevier Inc. All Rights Reserved. Neuromuscular Junction A: Courtesy of Don Fawcett, Harvard Medical School, Boston, Massachusetts. In Pollard TD: Earnshaw W: Cell biology, ed 2, St. Louis, 2007, Saunders Copyright © 2019, Elsevier Inc. All Rights Reserved. Excitation of a Muscle Fiber Copyright © 2019, Elsevier Inc. All Rights Reserved. Excitation and Contraction Nerve impulse travels over the sarcolemma and inward along the T tubules, which triggers the release of calcium ions Calcium binds to troponin, which causes tropomyosin to shift and expose active sites on actin Copyright © 2019, Elsevier Inc. All Rights Reserved. Role of Calcium in Muscle Contraction From Lodish H: Molecular cell biology, ed 4, New York, 2000, WH Freeman. Copyright © 2019, Elsevier Inc. All Rights Reserved. Molecular Basis of Muscle Contraction Copyright © 2019, Elsevier Inc. All Rights Reserved. Cross Bridges From Lodish H: Molecular cell biology, ed 4, New York, 2000, WH Freeman. Copyright © 2019, Elsevier Inc. All Rights Reserved. Sliding-Filament Model (Slide 1 of 2) When active sites on actin are exposed, myosin heads bind to them Myosin heads bend and pull the thin filaments past them Each head releases, binds to the next active site, and pulls again The entire myofibril shortens Copyright © 2019, Elsevier Inc. All Rights Reserved. Sliding-Filament Model (Slide 2 of 2) B: Courtesy H.E. Huxley, Brandeis University, Waltham, Ma. Copyright © 2019, Elsevier Inc. All Rights Reserved. Contracting Sarcomere Copyright © 2019, Elsevier Inc. All Rights Reserved. VIDEO Muscle Relaxation Immediately after the Ca++ ions are released, the sarcoplasmic reticulum begins actively pumping them back into the sacs Ca++ ions are removed from the troponin molecules, thereby shutting down the contraction Copyright © 2019, Elsevier Inc. All Rights Reserved. Energy Sources for Muscle Contraction: Skeletal Muscle Skeletal muscle contraction produces waste heat that can be used to help maintain the setpoint body temperature Copyright © 2019, Elsevier Inc. All Rights Reserved. Motor Units Some motor units consist of only a few muscle fibers, whereas others consist of numerous fibers Generally, the smaller the number of fibers in a motor unit, the more precise are the available movements; the larger the number of fibers in a motor unit, the more powerful the contraction available Copyright © 2019, Elsevier Inc. All Rights Reserved. Motor Unit B: Courtesy Dr. Paul C. Letourneau, Department of Anatomy, Medical School, University of Minnesota, Copyright © 2019, Elsevier Inc. All Rights Reserved. MN. Muscle Tone Tonic contraction: Continual, partial contraction of a muscle Muscles with less tone than normal are flaccid Muscles with more tone than normal are spastic Muscle tone is maintained by negative feedback mechanisms Copyright © 2019, Elsevier Inc. All Rights Reserved. Learning Objectives Lesson 17.3: Isotonic and Isometric Contractions, Muscle Types, and Muscular Disorders 10. Explain the graded strength principle. 11. Describe isotonic and isometric muscle contractions. 12. Describe the anatomical and functional characteristics of cardiac and smooth muscle. 13. Discuss major muscular disorders. Copyright © 2019, Elsevier Inc. All Rights Reserved. Isotonic and Isometric Contraction (Slide 1 of 2) Isotonic contraction Contraction in which the tone or tension in a muscle remains the same as the length of the muscle changes Isometric contraction Contraction in which muscle length remains the same while muscle tension increases Copyright © 2019, Elsevier Inc. All Rights Reserved. Isotonic and Isometric Contraction Copyright © 2019, Elsevier Inc. All Rights Reserved. Cardiac Muscle Found only in the heart Also known as striated involuntary muscle T tubules are larger and form diads with a rather sparse sarcoplasmic reticulum Cardiac muscle sustains each impulse longer than does skeletal muscle; therefore, impulses cannot come rapidly enough to produce tetanus Cardiac muscle is self-stimulating Copyright © 2019, Elsevier Inc. All Rights Reserved. Structure of Cardiac Muscle Copyright © 2019, Elsevier Inc. All Rights Reserved. Smooth Muscle (Slide 1 of 2) Smooth muscle is composed of small, tapered cells that have a single nucleus Ca++ comes from outside the cell and binds to calmodulin instead of troponin to trigger a contraction No striations are seen because the thick and thin myofilaments are arranged differently than in skeletal or cardiac muscle fibers Copyright © 2019, Elsevier Inc. All Rights Reserved. Smooth Muscle Fiber Skeletal VS Smooth muscle Photos: Courtesy Dr. Frederic S. Fay, Department of Physiology, University of Massachusetts, Worcester, MA. Copyright © 2019, Elsevier Inc. All Rights Reserved. The Big Picture: Muscle Tissue and the Whole Body Function of all three major types of muscle is integral to function of the entire body All three types of muscle tissue provide the movement necessary for survival Muscles maintain the body in a relatively stable position MUSCLUAR SYSTEM OVER VIEW Copyright © 2019, Elsevier Inc. All Rights Reserved.