ANPH111 Midterm Exam PDF

Cells are continually pushed toward the stratum Anatomy and Physiology granulosum Integumentary System 3.Stratum...

Cells are continually pushed toward the stratum Anatomy and Physiology granulosum Integumentary System 3.Stratum Granulosum Components of the Integumentary System named for its granular appearance 1. Skin cells begin to flatten and accumulate more 2. Hair keratin 3. Nails melanin can travel to cells within this layer 4. Associated Exocrine glands (contained in melanosomes) Integumentary Functions cells begin to die at the most superficial layers of responsible for protection of internal organs the stratum granulosum. Also aids in sensory function, thermoregulation > MELANOSOMES: and vitamin D synthesis where melanin stored in granules melanin Skin Layers produced by melanocytes in stratum basale. Epidermis long extensions transfer melanin to cells in a. Most superficial layer of skin made of stratum granulosum (organelles that holds keratinized stratified squamous melanin). epithelium b. Avascular NOTE: c. Contains 4-5 layers depending on Melanin — give pigments location. Melanosomes — stores melanin d. Thick Skin - found on palms and soles Melanocytes — cells that produces (5 layers) melanin e. Thin skin - found in all other locations Keratin — cell produced by (4 layers) keratinocytes Layers of Epidermis Keratinocytes — matured cells there are 4 to 5 layers in the epidermis (thick skin contains one additional layer). 4. Stratum Lucidum cells are produced in the deepest layer and migrate from only found in thick skin deepest layer to the superficial layer. located in palms and soles of feet. mature cells are called KERATINOCYTES (-cytes = cell) composed of tightly packed, dead keratinocytes keratin makes cells tough and water-resistant. cells contain ELEIDIN (a protein that functions as a water barrier) 1. Stratum Basale deepest of the epidermal layers single layer of 5. Stratum Corneum : (are all dead cells) cells most superficial layer of the epidermis actively divide to replace cells in superficial about 15 to 30 layers of dead keratinocytes layers additional cells found in stratum basale: cells are shed and lost due to mechanical forces > MERKEL CELLS: sensory receptors used for cells are replaced by cells in deeper layers discriminatory touch. migrating into the stratum corneum > MELANOCYTES: produce melanin to protect cells from UV radiation; all humans have similar concentration Dermal Papillae ofmelanocytes; activity of melanocytes leads to different — fingerlike projections of the dermis into the epidermis. skin tones. — helps to anchor the epidermis to the dermis (prevents > TWO FORMS OF MELANIN: the two EUMELANIN: black and brown pigment. layers from separating). PHEOMELANIN: (yellowish to) reddish pigment. — noticeable as fingerprints. 2. Stratum Spinosum Dermis eight to ten cell layers thick lies deep to the epidermis keratinocytes are shaped like FOOTBALLS : forms projections that extend into the epidermis pointed ends that look like spines give rise to the composed mainly of connective tissue name "spinosum" also contains: blood vessels, hair follicles, glands cells are continually pushed toward the stratum supports the epidermis with nutrients, strength, granulosum and elasticity. Langerhans (dendritic) cells provide immune protection Layers of the Dermis: MEDULLA: center of hair shaft — collagen fibers provide strength and CORTEX: surrounds medulla. structure; CUTICLE: surrounds cortex — elastic fibers provide elasticity. Hair Growth Layers of Dermis — Hair growth is not continuous. 1. Papillary Layer — Follicles alternate between more superficial layer of dermis growth and rest cycles. composed of loose areolar connective tissue — New growth pushes old hair contains dermal papillae that project up into the out of follicle. stratum basale of the epidermis. dermal papillae contain: 2. Nails > blood vessels — composed of keratinized epidermal cells > nerve fibers ANATOMY OF NAILS: > tactile (meissner's) corpuscles : used to detect NAIL BED: living component of nail light pressure NAIL BODY: visible hard portion of nail NAIL ROOT: proximal side of nail body (production of 2. Reticular Layer keratinocytes) deeper layer of the dermis NAIL CUTICLE (eponychium): thin layer of skin at much thicker than the papillary layer. base of nail made of dense irregular connective tissue. LUNULA: crescent-shaped region of nail bed contains hair follicles, blood vessels, and nerves PACINIAN CORPUSCLES: cells that sense deep 3. Sweat Glands pressure. — also known as SUDORIFEROUS GLANDS — produce sweat (perspiration) to aid in temperature Hypodermis regulation known as the subcutaneous layer/ superficial fascia. TWO TYPES OF SWEAT GLANDS lies deep to the dermis. ECCRINE SWEAT GLANDS composed of adipose & loose areolar connective — found all over the body tissue — less viscous sweat (malabnaw) provides insulation and cushioning — involved in thermoregulation highly vascularized — secrete a less viscous sweat onto surface of skin contains brown fat in infants (aids in APOCRINE SWEAT GLANDS thermoregulation in infants) — more viscous (malapot) secretion as it has lipids and FASCIA: connects skin to underlying muscle proteins —secretes a viscous sweat within hair follicles associated ACCESSORY STRUCTURES OF THE SKIN with pubic hair STRUCTURES ASSOCIATED WITH SKIN — not active till puberty — found in groin and axilla (armpit) 1. Hair note: — found on most body surfaces exceptions include Foul odor is due to bacteria in the apocrine glands palms and soles thick skin) Pheromone: chemicals that's produced by animals and — composed of dead, keratinized cells from humans used to communicate through sweat, urine, epidermis semen, — structures associated with hair: breast milk, and vaginal fluid. SEBACEOUS (OIL) GLANDS: secretes sebum (oil) ARRECTOR PILI MUSCLES: contract to make 4. Sebaceous Glands hair "stand-up" — usually associated with hair follicles — functions of hair include: physical protection, — secrete an oily mixture called SEBUM sensory input, thermoregulation, UV protection. — lubricate skin — secretion stimulated by hormones released during ANATOMY OF HAIR : (components of hair from puberty deep to superficial:) ACNE HAIR PAPILLA: blood supply to hair follicle — accumulation of sebum, keratin, and dead cells can HAIR BULB: deepest portion of follicle block hair follicles HAIR ROOT: between bulb and shaft — bacteria feed on sebum and sweat to grow HAIR SHAFT: visible portion above skin — this leads to inflammation called acne Functions of the Integumentary System Burns Protection — occur when damage is caused by heat, radiation, — keratin, sebum, and glycolipids protect against electricity, or chemicals water loss — skin cells die and can be replaced — DERMCIDIN in sweat and macrophages (immune SEVERITY OF BURNS cells) protect against microbes FIRST DEGREE BURNS: only affect epidermis — melanin protects against UV radiation SEOND DEGREE BURNS: affect epidermis and dermis Sensory Function THIRD DEGREE BURNS: affect epidermis, dermis, and — the skin contains different types of sensory hypodermis receptors found in various layers — meissner's corpuscles and pacinian corpuscles - Functions of the Integumentary System tactile sensations (touch, pressure, vibration, tickle) Estimating the size of a Burn Sensory Receptors of the Skin — Size of burn is important in determining treatment — THERMORECEPTORS: detects heat or cold — "Rule of nines" is used for estimation — NOCICEPTORS: detect pain Head and neck - 9% — TACTILE CORPUSCLES: detect touch Upper limbs - 9% each — LAMELLATED CORPUSCLES: detect pressure and Trunk - 36% vibration Genitalia - 1% Thermoregulation Lower limbs - 18% each — Sweat helps keep the body cool Wound Healing — Increased blood flow to the skin cools body Multi-step process: — Describe the changes in the integumentary system 1. Blood clotting that help keep the body warm on a cold day. Contrast 2. Fibroblasts produce new collagen those changes with the changes that help cool the (granulation tissue) body on a hot day. 3. Regeneration of epidermis -> The integumentary system adjusts blood flow to note: Scar may form after healing help regulate body temperature. Skin Cancer On a cold day, blood flow is diverted away from the — Associated with overexposure to UV radiation skin and toward the internal organs to maintain a > UV radiation causes mutations in DNA, leading to warmer temperature for those critical organs. Sweat increased cancer risk glands remain inactive. —Skin cancers vary depending on cell where the cancer On a hot day, blood flow through the skin is increased originated to allow for heat to dissipate from the body. Sweat Three forms of skin cancer: glands are activated to dissipate heat through the 1. Basal cell carcinoma - cause by cells of stratum basale skin. — affect cells on stratum basale Vitamin D Synthesis — most common cancer in United States; — Ultraviolet (UV) rays activate the precursor — occurs frequently in areas that are molecule to initiate vitamin D synthesis most susceptible to long term sun — Vitamin D aids in the absorption of calcium from exposure foods in the gastrointestinal tract 2. Squamous cell carcinoma - caused by keratinocytes of — Necessary for bone growth and immune function stratum spinosum — ERGOSTEROL (LIPID) - VITAMIN D (THROUGH UV — Squamous cell carcinoma is less RAYS) common than basal cell carcinoma — VITAMIN D - GOOD FOR BONES — More aggressive and can Rickets metastasize — Misshaped bones due to calcium deficiency in 3. Melanoma - caused by melanocytes children — Difficult to detect and highly — Bones are weak due to lack of calcium metastatic (spread cancer cells) — May develop into osteomalacia in adults Injuries — skin is highly vulnerable to injury (ex. abrasions, cuts, burns) — skin is highly regenerative — wound healing may lead to scars — Loss of accessory structures (hair, glands) — Repaired tissue may have a different texture or consistency Bone Tissue and The Skeletal System Articular cartilage — layer of hyaline cartilage that reduces friction Functions of the Skeletal System in joint The skeletal system is made of bone and cartilage Epiphyseal plate (growth plate) Functions include: — found in children — Providing rigid support framework of the human body — Contains growing cartilage that — Allowing movement as muscles pull on bones allows bones to increase in length — Providing protection for soft internal organs — Ossifies to become epiphyseal line in — Storing minerals in the bone extracellular matrix adults — Storing energy in the form of adipose in yellow bone Epiphyseal line marrow — site of previous epiphyseal plate — Production of blood cells Periosteum — dense irregular connective tissue lining Bone Functions surface — Attachment sites for muscles — Contains blood vessels, nerves, and lymphatic — Protection of internal organs vessels — Storage of calcium and other minerals — Tendons and ligaments attach to periosteum — Production of blood cells by perforating fibers — Storage of adipose tissue Endosteum — dense irregular connective Cartilage — tissue lining medullary cavity — Cartilage contributes to skeletal system > Elastic cartilage is not found in the skeletal system 2. Short Bones > Hyaline cartilage is found at the ends of bones where — Cube-like in shape they form joints — Approximately equal length, width, and – Helps bones glide past one another thickness – Loss of hyaline cartilage leads to osteoarthritis — Provide stability and support > Fibrocartilage is found between vertebrae, within the Examples: knee, and the pubic symphysis Carpal bones of the wrist Tarsal bones of the ankle Anatomy of a Typical Bone Periosteum — covers the surface of the bone 3. Flat Bones Outer shell of compact bone — protects entire bone — Usually thin, but can be curved Spongy bone — contains red bone marrow — Protect internal organs Medullary cavity — contains yellow bone marrow — Composed of a layer of spongy bone between two Articular cartilage — made of hyaline cartilage is found layers of compact bone at the joints Help protect internal organs (e.g., skull, ribs) Ligaments — attach bones to each other Spongy bone houses red bone marrow Examples: Bone Classification Cranial bones (skull), Sternum, Ribs, Scapula 1. Long Bones Articular Cartilage — Bones that are longer than they are wide — Found at ends of long bones where joints form — Function as levers — Made of hyaline cartilage Examples: — Reduce friction and act as shock absorber Humerus, Femur, Ulna, Tibia 4. Irregular Bones Common Structure of Long Bone — Do not have an easily characterized shape Epiphysis — Does not fit any other classification — end of long bone — Complex shapes Diaphysis Examples: — shaft of long bone Vertebrae Metaphysis Facial bones — between epiphysis and diaphysis — Location of epiphyseal plate/line 5. Sesamoid Bones Medullary cavity — Small, round bones suspended in a tendon or ligament — hollow space in diaphysis — Protect tendons from compressive force — Houses yellow bone marrow — Develop over time due to friction — Help protect tendons — Typically seen in tendons of feet, hands, and knees > More dense — Patella is the only common sesamoid bone in every > Provides support and protection person — Spongy bone Bone Markings > Provide strength to bone The surface features of bones / The Four General Classes > Spaces house red bone marrow of Bone Markings: > Articulating surfaces — where two bones meet Cells of Bone > Depressions — sunken portion of a bone Osteogenic cells — stem cells that replicate > Projections — projects above surface of bone — Develop into osteoblasts > Holes and spaces — an opening or a groove in the bone — Communicate via canaliculi Osteoblasts — cells that form new bone matrix 1. Articulating Surfaces Osteocytes — mature osteoblast that are completely Condyle — rounded surface — surrounded by matrix Facet — flat surface — Located in lacunae Head — prominent rounded surface Osteoclasts — cells that breakdown bone Trochlea — rounded articulating surface — Aid in bone remodeling 2. Depression Compact Bone Fossa— elongated basin Osteon — structural unit of compact bone Sulcus— groove Made of rings of matrix called concentric lamellae 3. Projections Concentric lamellae surround central canal Crest— ridge andprovide support Epicondyle— projection off a condyle Blood vessels in central canal connected to Line— slight, elongated ridge periosteum by perforating canals Process— prominent feature Nutrients and wastes move through canaliculi Ramus— long projection (branch) Spine— sharp process Spongy Bone Trochanter— rough round projection Contain osteocytes within trabeculae Tubercle— small, rounded process Trabeculae — beams of bone that form Tuberosity—rough surface lattice-like network within spongy bone Form along stress lines to provide strength 4. Holes and Spaces Spaces house red bone marrow where Canal— passage in bone hematopoiesis occurs Fissure— slit through bone Foramen— hole through bone Formation and Growth of Bone and Cartilage Meatus— opening into canal Formation of Bone Sinus— air-filled space in bone Ossification — the process of forming bone A cartilage or membranous model is required Microscopic Structure of Cartilage and Bone New bone tissue is built on the model Three Types of Cartilage Intramembranous ossification — connective tissue Hyaline, elastic, and fibrocartilage membrane is used to make bone — Chondroblasts - cells of cartilage that secrete Endochondral ossification — hyaline cartilage is used matrix to make bone — Chondrocytes - cells that are completely surrounded by matrix (Found in lacunae) Intramembranous Ossification — Forms flat bones of cranium and face Cartilage Tissue — Mesenchymal cells group together and differentiate — Semi-solid connective tissue into — Avascular osteoblasts forming ossification center — Covered by perichondrium — Osteoblasts begin to secrete osteoid > Dense irregular connective tissue — Trabeculae and periosteum form > Contains blood vessels — Compact bone surrounds trabecular bone > Provides nutrients to cartilage Endochondral Ossification Bone Tissue — Forms most long bones — Solid connective tissue — Cells in cartilage differentiate into osteoblasts — Compact bone — Minerals are deposited on collagen fibers in cartilage > Zone of calcified matrix - dead chondrocytes surrounded starting at by bone matrix diaphysis - Anchors epiphyseal plate to diaphysis — Perichondrium becomes periosteum — Blood vessels penetrate periosteum forming primary How Bones Grow in Diameter ossification center — Occurs by appositional growth > Mineralization increases — Osteoblasts in periosteum form new matrix on surface — Cartilage remains at epiphyseal plate to allow bone to of bone grow in length — Osteoclasts break down older bone that lines medullary — Epiphyses ossify after birth at secondary ossification cavity centers Bone Remodeling Ossification of Embryonic and Fetal Skeletons The changes bones go through on a daily basis — Embryonic and fetal skeletons form by combination of Bone is constantly broken down and new bone is formed intramembranous and endochondral ossification Aids homeostasis by making minerals available — Long bones are formed via endochondral ossification Caused by injury, exercise, and other activities — Flat bones are formed via intramembranous ossification Bone remodels to increase strength along line of — Mineralization increases during development resistance Growth, Repair, and Remodeling Blood Calcium Regulation — Bones store calcium and other minerals Cartilage Growth —Hormones influence bone: Interstitial cartilage growth-cartilage grows longer > Calcitonin causes bones to take up calcium (Lowers Due to mitotic replication of chondrocytes blood calcium Allows bone to increase in length levels) Appositional cartilage growth-cartilage grows wider — Parathyroid hormone causes Occurs as cells in perichondrium become chondroblasts > bones to release calcium and secrete matrix > Increases blood calcium levels Allows bone to increase in width Hormones that Influence the Skeletal System Interstitial Cartilage Growth Growth hormone (GH) - promotes bone growth — Chondrocytes divide by mitosis which allows T3 and T4 - promotes bone growth cartilage to grow in length Estrogen and testosterone - increase osteoblast activity — Initially share same lacuna Calcitriol - increases absorption of calcium and — Chondrocytes move apart as they secrete matrix phosphate from intestine PTH - increases osteoclast activity Appositional Cartilage Growth Calcitonin - increases osteoblast and decreases —Allows cartilage to increase in width osteoclast activity — Cell in perichondrium differentiate into chondroblasts Bone Repair — Chondroblasts secrete matrix allowing increase in Fracture — break of a bone width Steps in bone repair: 1. Hematoma prevents blood loss How Bones Grow in Length 2. Cartilage callus forms new bone template — Epiphyseal plate grows 3. Callus is replaced by bone — The increase in size increases the distance 4. Compact bone is built around the outer surface of bone between the epiphysis and diaphysis — Cartilage on the diaphysis side of the plate is Assisting Bone Repair replaced with bone Reduction = aligning of bones for optimal healing — Bone is longer as a result > Should be done as soon as possible Cylinders and screws can be added surgically for Anatomy of Epiphyseal Plate stabilization Epiphyseal plates exhibit four zones of activity > Reserve zone - anchors epiphyseal plate to epiphysis Types of Fractures > Proliferative zone - chondrocytes that recently Fractures classified based on complexity, location, and underwent mitosis other features > Zone of mature cartilage - older, more mature 1. Closed (Compound) — A fracture in which the skin chondrocytes remains intact 2. Open (Simple) — A fracture in which at least one end of Increases risk of fracture the broken bone tears through the skin; carries a high risk of infection Osteoporosis 3. Transverse — Occurs straight across the long axis of — Characterized by a decrease in bone mass with age the bone — Rate of bone resorption exceeds rate of bone formation 4. Spiral — Bone segments are pulled apart as a result of a — Osteoclasts more active than osteoblasts twisting motion — Rapidly declining levels of estradiol in females 5. Comminuted — Several breaks result in many small increases risk pieces between two large segments 6. Impacted — One fragment is driven into the other, Classification of Joints usually as a result of compression Joints 7. Greenstick — A partial fracture in which only one side — Sites where bones and cartilage form a of the bone is broken connection 8. Oblique — Occurs at an angle that is not 90 degrees — Also known as an articulation or arthrosis Bones and Homeostasis Two Classification of Joints Nutrition and Bone Tissue 1. Structural — based on the structure that Calcium is stored in the extracellular matrix of bone connects the articulating surfaces of bones Hypocalcemia - low blood levels of calcium 2. Functional — based on the amount of Hypercalcemia - high blood levels of calcium movement between articulating bones Parathyroid hormone (PTH) - stimulates osteoclasts > The breakdown of bone increases blood calcium 1. Structural Classification Calcitonin (CT) - inhibits osteoclasts — Based on the structure of the articulating surfaces > Increased formation of bone decreases blood calcium Fibrous : joined by fibrous connective tissue Cartilaginous : joined by cartilage Calcium Homeostasis : Hyaline cartilage or fibrocartilage Bones store calcium Synovial : joined within a fluid-filled joint cavity Calcitonin and parathyroid hormones aid in : Most common joint calcium homeostasis Calcium is absorbed by small intestine 2. Functional Classification > Requires vitamin D for absorption — Based on the extent of joint mobility Synarthrosis — little to no movement Dietary Calcium — Example: sutures of skull Good sources of dietary calcium include: Amphiarthrosis — slight movement - Cheese — Examples: pubic symphysis, intervertebral discs - Milk - Nuts Functional Classification - Leafy greens Diarthrosis : significant movement - Fish Three categories based on axes of motion 1. Uniaxial — movement in one plane Importance of Vitamin D > Example: elbow Vitamin D is synthesized by the body 2. Biaxial — movement in two planes > Not found in many foods > Example: metacarpophalangeal joints Can be added to foods like milk and 3. Multiaxial — movement in three or more planes cereal for supplementation > Example: hip and shoulder joints Vitamin D Synthesis Structural and Functional Relationship — Human body can produce vitamin D — The structure of a joint determines which types of > Requires exposure to sunlight/UV radiation movement are possible — Activated by kidneys — Fibrous and cartilaginous joints > Active forms = calcitriol and calcidiol > Functionally are synarthroses or amphiarthroses — Travels through blood to small intestine — Synovial joints > Facilitates calcium absorption by small intestine > Functionally are diarthroses Exercise and Bone Tissue Exercise and physical stress strengthen bones Increased exercise leads to thicker, denser bones Lack of exercise leads to weaker, lighter bones Types of joints increase in skeletal size 1. Fibrous Joints > Allows epiphyseal plate to increase in size, leading — No joint cavity to increase in bone length — Bones held together by dense (fibrous) — Classified as synarthroses connective tissue — Examples: epiphyseal plates, costal cartilage — Synarthroses : Permit little to no movement Types: Symphyses Sutures — Cartilaginous joint formed using fibrocartilage Syndesmoses — Permit strong attachment while allowing limited Gomphoses movement — Classified as amphiarthroses Types of Fibrous Joints — Examples: pubic symphysis, intervertebral symphyses Suture 3. Synovial Joints — Joins the bones of the skull — Contain a joint cavity — Classified as synarthroses (Some may allow slight > Bones do not directly touch movement) — Articular capsule : forms walls of cavity — Convoluted shape prevents movement between bones > Ligaments : to attach bones — Form when skull bones completely ossify during early > Synovial membrane : secretes synovial fluid childhood : Lubricates joint and nourishes cartilage — Articular cartilage : hyaline cartilage at ends of bones Newborn Skull — Classified as diarthroses — Newborn skull contains wide areas of connective tissue between bones called fontanelles Supporting Structures — Provide flexibility to skull during birth Ligaments : strong bands of fibrous connective — Allow for rapid growth of brain after birth tissue — Fontanelles ossify over time — Strengthen and support joint by anchoring bone together Syndesmoses 1. Extrinsic ligaments are located outside of articular — Joins two parallel bones using fibrous connective capsule tissue 2. Intrinsic ligaments are incorporated into wall of > Space between bones may be narrow or wide articular capsule > Wide spaces are filled by an interosseus membrane 3. Intracapsular ligaments are located inside of articular — Functionally classified as amphiarthroses capsule — Found between radius and ulna of forearm and Tendons : connective tissue structure that attaches between tibia and fibula of leg muscle to bone > Interosseus membrane anchors parallel bones to each other Cushioning Structures > Interosseus membrane between radius and ulna is Articular discs and menisci more mobile — Pads of fibrocartilage between bones — Provide shock absorption and help smooth Gomphoses movements — Anchors teeth to maxilla (upper jaw) and mandible Bursae and tendon sheaths (lower jaw) — Prevent friction between bone and tendons — Made of numerous short bands of dense connective Fat pads tissue called periodontal ligaments — Provide cushioning — Classified as synarthroses Bursae and Tendon Sheaths 2. Cartilaginous Joints — Both contain additional pockets of synovial fluid — Bones joined by hyaline cartilage or fibrocartilage located outside of joint — Synchondroses : Joined by hyaline cartilage > Bursae are small sacs of synovial fluid — Symphyses : Joined by fibrocartilage > Tendon sheaths are elongated and wrap around tendons where they cross a joint Types of Cartilaginous Joints — They function to reduce friction between bones and muscle tendons or skin Synchondroses — Cartilaginous joint using hyaline cartilage — Found in every long bone early in life to allow  Types of Synovial Joints Hip Replacement Pivot Joint — Severely arthritic joints may require surgery to alleviate — Rounded portion of a bone enclosed in a ring pain — Allows rotation around one axis > Surgery replaces the articular surfaces of the bones with — Uniaxial joint artificial materials — Atlantoaxial joint — Hip replacement surgery replaces head and neck of > Formed between C1 and C2 vertebrae femur and acetabulum of pelvis Hinge Joint — Convex end of one bone articulates with the The Axial Skeleton concave end of another Divisions of the Skeletal System — Allows bending and stretching along one axis — Consists of all the bones, cartilage, and ligaments of the Uniaxial joint body — Elbow, knee, ankle, and interphalangeal joints — 206 bones in adult skeleton — More in children Condyloid Joint — Provides support for the body — Shallow depression at the end of one bone — Aids in body movements articulates with rounded structure from nearby — Assists in calcium homeostasis bone or bones — Divided into axial and appendicular divisions — Biaxial joint — Allows bending and straightening, anterior- Axial Skeleton posterior movements — Forms vertical, central axis of the body — Metacarpophalangeal joints — Protects internal organs — Allows movement of head, neck, back, and respiratory Saddle Joint muscles — Both articulating surfaces have a saddle shape — Consists of 80 bones in total: — Biaxial joint Skull — Allows almost circular movement Vertebral column — First carpometacarpal joint, sternoclavicular Ribs joint Sternum Appendicular Skeleton Plane Joint — Forms upper and lower extremities — Surfaces of the bones are mostly flat — Includes bones that attach extremities to axial skeleton — Bones slide past each other during motion — 126 bones in total — Limited motion, but multiaxial joint — Intercarpal joints, intertarsal joints, The Skull acromioclavicular joint — Composed of 22 bones — Bones are divided into two groups: Ball-and-Socket Joint Cranial bones : surround and protect the brain — Rounded head of one bone fits into the bowl-shaped Facial bones : form the face, nasal cavity, mouth, and socket orbit of another — Form openings called cavities — Great range of motion > Contain soft organs — Multiaxial joint > Decrease weight of skull — Hip joint, shoulder joint Bones of the Skull Cranial bones Joint Damage — Frontal bone (1) — Arthritis = inflammation of a joint — Parietal bones (2) — Leads to pain, swelling, stiffness, and reduced mobility — Occipital bone (1) of the joint — Temporal bones (2) — Most common form is osteoarthritis — Sphenoid bone (1) > Caused by degeneration of articular cartilage — Ethmoid bone (1) — Other causes include gout, autoimmune conditions, joint infections, and genetic causes Facial bones — Mandible (1) — Maxillae (2) — Lacrimal bones (2) — Nasal bones (2) — Palatine bones (2) > Medial and lateral pterygoid processes — Zygomatic bones (2) — Inferior nasal conchae (2) Ethmoid Bone — Vomer (1) — Forms part of orbit and nasal cavity Bony markings: Unpaired and Paired Skull Bones > Perpendicular plate — Paired skull bones are found on > Superior and middle nasal conchae the left and right sides > Crista galli — Some bones are unpaired > Cribriform plate > Olfactory foramina Cavities of the Skull — Cavities house softer structures Mandible Cavities include: — Forms lower jaw > Cranial cavity — Only moveable bone of skull > Orbits Bony markings: > Nasal cavity > Body, ramus, and angle > Oral cavity > Coronoid and condylar processes > Paranasal sinuses > Mandibular notch > Mental foramina Frontal Bone > Mental protuberance — Forms the forehead and part of cranium Bony markings: Maxillary Bone > Glabella — Also called the hard palate or maxilla > Supraorbital margin — Forms the upper jaw, most of the roof of the > Supraorbital foramen mouth, part of the orbit, and the lateral base of the nose Parietal Bones Bony markings: — Form superior lateral sides of the skull > Alveolar processes — Articulate with frontal, temporal, and > Infraorbital foramen occipital bones Lacrimal Bones Occipital Bone — Form part of orbit — Forms posterior skull and posterior base of cranial Contain lacrimal glands that secrete tears cavity Bony markings: Palatine Bones > External occipital protuberance — Form posterior portion of hard > Superior nuchal line palate, medial part of orbit, and > Foramen magnum contributes to vertical section of > Occipital condyles nasal cavity Temporal Bones Zygomatic Bones — Form lower lateral sides of skull — Known as the cheekbones Bony markings: Forms much of the lateral part of orbit > Squamous portion Bony markings: > Zygomatic process > Temporal process > Mastoid process — Unites with zygomatic process of temporal bone to > External acoustic meatus form zygomatic arch > Mandibular fossa > Articular tubercle Vomer, Nasal, and Inferior Nasal Conchae Bones > Styloid process Vomer — Forms part of nasal septum Sphenoid Bone Nasal bones — Forms much of the base of central skull and part of — Form bony base (bridge) and lateral walls the nose temples Inferior nasal conchae Bony markings: — Project into nasal cavity > Greater and lesser wings > Sella turcica > Pituitary fossa The Articulated Skull The Thoracic Cage — Anterior view of articulated skull Sternum — Many of the bones of the skull can be Parts of sternum identified anteriorly 1. Manubrium — Clavicular notch Sutures — Suprasternal notch — Immobile joints filled with dense, fibrous connective 2. Body tissue that attach cranial bones — Joins to manubrium at sternal angle Sagittal suture — connects the two parietal bones 3. Xiphoid process Coronal suture — connects frontal bone to parietal — Clavicles and some ribs attach to sternum bones Lambdoid suture — connects parietal bones to occipital Ribs bone — Twelve pairs of curved flat bones Squamous suture — connects parietal and temporal — Costal cartilage articulates some to the sternum bones anteriorly — Bony features: The Orbit Head, neck, body, tubercle, and angle of the rib — Protects the eyeball and muscles that move it Costal groove — Frontal, zygomatic, maxilla, ethmoid, lacrimal, Types of Ribs — palatine, and sphenoid bones contribute to orbit — Only some ribs have costal cartilage — Optic canal allows entry of optic nerve True ribs (1-7) — costal cartilage directly — Superior orbital fissure allows entry of blood attaches to sternum supply False ribs (8-12) — costal cartilage does not attach to sternum The Nasal Cavity, Septum, and Conchae Floating ribs (11-12) — do not have costal — Nasal cavity is bordered by maxillae and nasal bones cartilage Nasal septum : divides nasal cavity > Formed by perpendicular plate of ethmoid, vomer, and The Appendicular Region septal cartilage Appendicular Skeleton Nasal conchae — Composed of: > Covered by mucous membranes Bones found in the upper and lower limbs > Warm, filter, and moisten inhaled air > Humerus, ulna, radius, carpal bones, bones of the hand > Femur, tibia, fibula, patella, tarsal bones, bones of the The Vertebral Column foot — Twenty-four vertebrae in total plus the Bones that attach the limbs to axial skeleton sacrum and the coccyx > Shoulder girdle - clavicle and scapula Five regions of vertebral column: > Pelvic girdle-os coxae > Cervical (7) > Thoracic (12) Timeline of Skeletal Development > Lumbar (5) — Appendicular skeleton development begins before birth > Sacral (5 fused vertebrae) — Continues through early adulthood > Coccygeal (4 fused vertebrae) — Completion occurs around age 25 Curvatures of the Vertebral Column Anatomy of a Limb — Four curvatures increase strength, flexibility, and shock — Mammals have similar limb construction absorption — Single, strong bone close to trunk Cervical curve (posteriorly oriented) — A hinge joint connecting two distal bones Thoracic curve (anteriorly oriented) — A complex joint made of a series of short bones Lumbar curve (posteriorly oriented) — A hand, foot, or wing made of rows of small bones Sacrococcygeal curve (anteriorly oriented) The Shoulder Girdle Curvature Abnormalities Bones of the Shoulder Girdle Kyphosis - excessive posterior curvature of — The clavicle and scapula compose the shoulder girdle thoracic region — Anchor the upper limb to the axial skeleton Lordosis - excessive anterior curve of lumbar — Facilitate movement of the upper limb region > Serve as attachment sites for muscles that move shoulder Scoliosis - abnormal lateral curvature of vertebral and arm column Clavicle > Pronation occurs as the palm faces inferiorly — Also known as the collarbone > Supination results in the palm facing superiorly — Loosely-anchored, S-shaped bone — Articulates medially with manubrium of sternum Bones of the Wrist: Carpals — Forms sternoclavicular joint — Eight bones arranged into two rows — Articulates laterally with acromion of scapula Proximal row (lateral to medial) — Forms acromioclavicular joint > Scaphoid, lunate, triquetrum, pisiform Distal row (lateral to medial) Scapula > Trapezium, trapezoid, capitate, hamate — Located on posterior of shoulder — Glenoid cavity articulates with head of humerus Bones of the Hand: Metacarpals and Phalanges > Forms glenohumeral joint — Five metacarpals in the palm of hand — Coracoid and acromion processes — Fourteen phalanges found in fingers (three in each — Scapular spine finger, two in the thumb) — Supraspinous, infraspinous, and subscapular fossa Named according to relative position Three borders: > Proximal, middle, and distal phalanges > Superior, medial and lateral borders > Thumb only has proximal and distal phalanges Superior and inferior angles Fractures of Upper Limb Bones Bones of the Arm — Usually occur as a result of breaking a fall — Outstretched hand sends force through upper Bones found in the Arm limb — Humerus > Force may result in fracture — Ulna — Surgical neck, transverse, supracondylar, and — Radius intercondylar fractures of the humerus — Carpal bones — Colles' fracture of the radium — Metacarpal bones of the hands — Scaphoid fractures in the wrist — Phalanges of the fingers Bones of the Leg Humerus — Head of humerus articulates with glenoid cavity of Bones found in the Leg scapula at shoulder — Femur — Multiple sites for muscle attachment — Tibia — Distal end forms elbow — Fibula > Trochlea and olecranon fossa articulate with ulna — Tarsals, metatarsals, and phalanges of the foot > Capitulum articulates with radius Femur Ulna — Found in thigh region — Medial bone of antebrachial region — Longest, strongest bone of the body — Proximal end resembles shape of the letter "C" — Head articulates with acetabulum of os — Olecranon and coronoid processes form trochlear coxae to form hip joint notch — Multiple markings for muscle attachment > Articulates with trochlea of humerus at elbow — Medial and lateral condyles articulate — Allows hinge-like motion of forearm with the tibia to form knee joint Radius The Distal Femur — Lateral bone of antebrachial region — Medial and lateral condyles articulate with tibia to — Head articulates with capitulum of humerus at form knee joint elbow — Intercondylar fossa accommodates ligaments of the — Rotates around ulna to allow pronation and knee supination of forearm > Anterior and posterior cruciate ligaments — Interosseous membrane is between radius and ulna — Patellar surface articulates with patella — Distal end articulates with carpal bones Patella Supination and Pronation — Largest sesamoid bone of the human body — Movements that occur as the radius rotates around — Only sesamoid bone found in all humans the ulna — Increases leverage power of thigh muscles — When the elbow is flexed: Tibia and Fibula — Carries messages to and from the spinal cord — Found in lower leg and the brain Tibia > medial bone note: CNS and PNS are made of nervous tissue; Neurons = > Condyles articulate with femur to form knee joint cells capable of communication; > Tibial tuberosity Glial cells = cells that provide structure and support to neurons > Medial malleolus Fibula Neurons > Lateral bone — There are 100 billion nerve cells called NEURONS > Head and lateral malleolus within the cerebral cortex and > Used for muscle attachment white matter. Each of these nerve cells communicates with between 1,000 and Bones of the Foot: Tarsals 10,000 other nerve cells around our body. The millions of — Proximal row of tarsals: message pass through the Talus—articulates with tibia and fibula to form ankle brain every second enable us to think, to feel, to move, and Calcaneus—heel bone to control all our body Navicular processes automatically — Distal row of tarsals: — another term for nerve cell with its processes dendrites, Cuboid, medial cuneiform, intermediate cuneiform, axon and nerve cell lateral cuneiform body (nucleus) is the structural unit of the nervous system. Dendrite Bones of the Foot: Metatarsals and Phalanges — a nerve fiber, typically branched, which conduct a nerve Metatarsals impulse toward the cell — Make up the arch of the foot body. — Numbered 1-5 (I-V) starting at the medial side of the Axon foot — a nerve fiber which conducts nerve impulses away from 14 phalanges in the toes the cell body. — Toes numbered 1-5 starting at the big toe (hallux) Synapse — Named proximal, middle, and distal according to — the junction gap between the axon of one neuron and relative position the dendrite of the next — Hallux only has proximal and distal phalanges Arches of the Foots — Help the bones of the foot distribute and absorb the force of impact > Flatten upon impact — Medial longitudinal arch — Lateral longitudinal arch — Transverse arch The Nervous System CENTRAL NERVOUS SYSTEM Nervous System The central nervous system (CNS) is made up of the — The master controlling and communicating system of brain and spinal cord. It is one of 2 parts of the the body nervous system. The other part is the peripheral nervous Functions: system, which consists of nerves that connect > Sensory input - monitor stimuli occurring inside & the brain and spinal cord to the rest of the body. outside body The central nervous system is the body's processing > Integration - interpretation of sensory input center. > Motor output - response to stimuli by activating effector Brain organs — the most complex part of the nervous system and the control system of the body. Organization of the Nervous System — it is protected by the bones of the skull Central nervous system (CNS) Function — Brain and spinal cord > the site of consciousness and intellectual function, — Integration and command center memory Peripheral nervous system (PMS) and emotions — Paired spinal and cranial nerves > monitors and regulates many unconscious bodily processes Divided into 3 Regions: 1. Cerebrum / Forebrain 2. Cerebellum / Hindbrain 3. Brain Stem Cerebrum/ Cerebral Hemispheres/Telencephalon — The most anterior and largest part of the brain — The entire surface of the cerebral hemispheres exhibits elevated ridges of tissue called gyrus, separated by shallow grooves called sulcus. — Less numerous are the deeper grooves called fissures, Major Regions of the Brain: which separate large regions of the brain Telencephalon (Cerebrum) Cerebellum / Metencephalon — Conscious thought processes, — projects dorsally under the occipital lobe of the intellectual functions cerebrum has two — Memory storage and processing hemispheres and a convoluted surface has an outer cortex — Conscious and subconscious regulation made up of gray of skeletal muscle contractions matter and an inner region of white matter — It provides the precise timing for skeletal muscle Diencephalon activity and controls — Thalamus : Relay and processing our balance and equilibrium. centers for sensory information — Because of its activity, body movements are smooth and — Hypothalamus : Centers controlling coordinated. emotions, autonomic functions, and hormone production Brain Stem — About the size of a thumb in diameter and Mesencephalon (Midbrain) approximately 3 — Processing of visual and auditory data inches long — Generation of reflexive somatic motor — Provides a pathway for ascending and descending tracts responses — Has many small gray matter areas and these nuclei are — Maintenance of consciousness part of the cranial nerves and control vital activities such as breathing and blood pressure Metencephalon (Pons) — Relays sensory information to The Spinal Cord cerebellum and thalamus — A long, thin, tubular bundle of nerves that is an — Subconscious somatic and visceral extension of motor centers the central nervous system from the brain and is enclosed in and protected by the bony vertebral column. Myelencephalon (Medulla Oblongata) — The main function is transmission of neural inputs — Relays sensory information to between the periphery and the brain. thalamus — it is the main pathway for information connecting the — Autonomic centers for regulation of brain and peripheral nervous system. visceral functions such as cardiovascular, — The length is about 45 cm long in men and 43 cm in respiratory, and digestive activities women, ovoid-enlarged in shape, and is enlarged in the cervical and lumbar regions. Metencephalon (Cerebellum) — Coordinates complex somatic 3 Meninges/Coverings motor patterns Outer dura mater : outer layer of spinal cord — Adjusts output of other somatic Arachnoid mater : sticky layer motor centers in brain and spinal cord Pia mater : innermost protective layer of the spinal cord (transparent color) Cross-section through the spinal cord at the Cranial Nerves mid-thoracic level CN I (1) : Olfactory Nerve— sensory for smell Gray Matter of the Spinal Cord and Spinal Roots CN II (2) : Optic Nerve— sensory for vision — The gray matter looks like a butterfly or CN III (3) : Oculomotor Nerve— Motor nerve for eye the letter H in cross section movement — 2 Posterior Projections: dorsal or posterior CN IV (4) : Trochlear Nerve— Motor nerve for eye horns movement — 2 Anterior Projections: ventral or anterior CN V (5) : Trigeminal Nerve— Sensory for face; horns surrounds the central canal of the cord, — Motor to muscles of mastication (chewing) which contains CSF CN VI (6) : Abducens Nerve— Motor for eye movement CN VII (7) : Facial Nerve— Motor to facial muscles; White Matter of the Spinal Cord — Sensory for taste — White matter of the spinal cord is composed CN VIII (8) : Vestibulocochlear nerve — Sensory for of myelinated fiber tracts : some running to hearing and balance higher centers, some traveling from the brain to CN IX (9) : Glossopharyngeal Nerve — Motor topharynx; the cord, and some conducting impulses from one — sensory for taste side of the spinal cord to CN X (10) : Vagus Nerve—Sensory and motor functions — each column contains a number of fiber tracts of thoracic and abdominal viscera made up of axons with the same destination and CN XI (11) : Accessory Nerve — Motor to function sternocleidomastoid and trapezius — divided into 3 CN XII (12) : Hypoglossal Nerve— Motor to tongue Regions: > posterior column 2nd Division: Autonomic Nervous System > lateral column — Also called the involuntary nervous system responsible > anterior column for coordinating involuntary Spinal Cord Segments functions, such as breathing and digestion — it is divided into 31 different segments, with motor — It is composed of a special group of neurons that nerve roots exiting in the ventral aspects and sensory regulate nerve cardiac muscle, smooth muscles, and glands roots entering in the dorsal aspects —the ventral and dorsal roots later join to form paired 2 Divisions: spinal nerves one on each side of the spinal cord 1. Sympathetic Nervous System : (Fight of Flight) 2. Parasympathetic Nervous System : (Resting and Digesting) 1. Sympathetic Nervous System — Also called the thoracolumbar division because its first neurons are in the gray matter of the spinal cord from T1 through L2. — ALSO REFERRED AS "FIGHT or FLIGHT" — Signs of this system are a pounding heart; rapid, deep breathing; cold, sweaty skin; a prickly scalp; and dilated eye pupils. Peripheral Nervous System — Under such conditions, it increases heart rate, blood — Consists of nerves and scattered groups of neuronal cell pressure, and blood glucose levels; dilates the bronchioles bodies of the lungs; brings about many other effects that help (ganglia) found outside the CNS the individual copes with the stressor. — It exposed to toxins and mechanical injuries — It provides communication lines between 2. Parasympathetic Nervous System CNS and the body's muscles, glands, and sensory receptors — Most active when the body is at rest and not 2 Divisions: threatened in any way > Sensory-Somatic System > Autonomic Nervous system — Sometimes called the "resting-and- digesting" system and; —also considered as the "housekeeping" system of the Myelin Sheath body — Whitish, fatty (lipoprotein), segmented sheath around — Chiefly concerned with promoting normal digestion most long axons. and — Protection of the axon. elimination of feces and and urine and with conserving — Electrically insulating fibers from one another. body energy, particularly by decreasing demands on the — Increasing speed of nerve impulse transmission. cardiovascular system Nodes of Ranvier (Neurofibril Nodes) Histology of Nerve Tissue — Gaps in myelin sheath between adjacent Schwann Two principal cell types of nervous system : cells sites where collaterals can emerge — Neurons : excitable cells that transmit electrical signals (responsive to stimuli) Unmyelinated Axons — Supporting cells : cells that surround and wrap neurons; — Schwann cell surrounds nerve fibers but coiling does Neuralgia not take place — Schwann cells partially enclose 15 or more axons Supporting Cells : Neuroglia / Glia — Provide supportive scaffolding for neurons Axons of the CNS — Segregate and insulate neurons — myelinated and unmyelinated fibers present — Guide young neurons to the proper connections — Myelin sheaths formed by oligodendrocytes — Promote health and growth — Nodes of Ranvier widely spaced no neurilemma Astrocytes Nerve Impulse — Most abundant, versatile, and highly branched glial Electrical Conditions of a Resting Neuron's Membrane cells in the CNS At rest= POLARIZED — cling to neurons; cover capillaries Fewer positive ions on the inner face of the neuron's Function: plasma membrane than there > Support and brace neurons are on its outer face > Anchor neurons to their nutrient supplies As long as the inside remains more negative than the > Guide migration of young neurons outside, the neuron will stay > Control the chemical environment (blood-brain barrier) INACTIVE > Participates in information processing in the brain Action Potential Initiation and Generatio Microglial Cells Most neurons in the body are excited by — Microglia : small, ovoid cells with spiny processes neurotransmitter chemicals released by other neurons. — Phagocytes : monitor health of neurons Normally, Na ions — Ependymal cells : range in the shape from squamous- cannot diffuse through the plasma membrane to any to columnar-shaped cells and are ciliated line cavities of greater extent, but when stimulated, the "gates" of Na brain spinal column channels open. Because Na is in much higher concentration outside Oligodendrocytes, Schwann Cells, and the cell, it diffuses into the neuron Satellite Cells This inward push of Na ions changes polarity of the — Oligodendrocytes : branched cells that wrap CNS neuron's membrane at that site= DEPOLARIZATION nerve fibers — Schwann cells (neurolemmocytes) : surround fibers Action Potential of the PNS If the stimulus is strong enough and the Na influx is — Satellite cells : surround neuron cell bodies with great enough, the local depolarization ganglia located in the PNS (graded potential) activates neurons to initiate and transmit a long-distance signal called STRUCTURAL CLASSIFICATIONS OF NEURONS "ACTION POTENTIAL" also called "NERVE IMPULSE" in neurons. Multipolar neurons - many extensions from the cell body Repolarization Bipolar neurons - one axon and one dendrite After the Na ions rush into the neurons, the membrane Unipolar neurons - have a short single process leaving permeability changes, becoming the cell body impermeable to Na ions but permeable to K ions. This outflow of positive ions from the cell restores the electrical conditions at the membrane to the polarized, or resting state = REPOLARIZATION  Until repolarization occurs, a neuron cannot conduct Typically composed of two parts: another impulse 1. Axonal terminal of the presynaptic neuron, which contains synaptic vesicles Changes in Membrane Potential 2. Receptor region on the dendrite(s) or soma of Caused by three events: the postsynaptic neuron 1. Depolarization — the inside of the membrane becomes less negative Synaptic Cleft 2. Repolarization — the membranes returns to its — Fluid-filled space separating the presynaptic and resting membrane potential postsynaptic neurons 3. Hyperpolarization - increase in the membrane — Prevent nerve impulses from directly passing from one potential, the inside of the membrane becomes more neuron to the next as in an electrical synapse negative than the resting potential — Transmission across the synaptic cleft: > Is a chemical event (as opposed to an electrical one) Saltatory Conduction > Ensures unidirectional communication between neurons — Fibers that have myelin sheaths conduct impulses much faster because the nerve impulse literally jumps or leaps, Synaptic Cleft: Information Transfer from node to node along the length of the fiber. — Nerve impulse reaches the axon terminal of the — This faster type of electrical impulse propagation is presynaptic neuron. called saltatory (saltare= to dance/leap) conduction — Neurotransmitter is released into the synaptic cleft. — Neurotransmitter crosses the synaptic cleft and binds Homeostatic Imbalance to receptors on the postsynaptic neuron. — Sedatives and anesthetics block nerve impulse by — Postsynaptic membrane permeability to ions changes, altering membrane permeability to ions, mainly Na ions causing an excitatory or inhibitory effect — Continuous pressure hinder impulse conduction depending on the ions controlled because they interrupt blood circulation to the neurons How does the electrical impulse traveling along one neuron get across the synapse to the next neuron (effector cell) to influence its activity? Transmission of the Signal at Synapses Answer: Impulse doesn't. Instead, a neurotransmitter chemical crosses the synapse to transmit the signal from one neuron to the next Neurotransmitters cell. — Chemicals used for neuronal communication with the body and the brain. Synapses — 50 different neurotransmitter have been identified — A junction that mediates information transfer — Classified chemically and functionally. from one neuron: > To another neuron Chemical Neurotransmitters > to an effector cell Acetylcholine (ACh) - stimulates skeletal muscles — Presynaptic neuron - conducts impulses toward (muscle contraction) the synapse Biogenic amines - Play roles in emotional behaviors and — Postsynaptic neuron - transmits impulses away our biological clock from the synapse Amino acids - Inhibitory neurotransmitter of the spinal cord. Electrical Synapses Peptides - runner's high (inhibit pain-sensing neurons) — Are far less common than chemical synapses — Correspond to gap junctions found in other cell — types Contain intracellular protein channels — Permit ion flow from one neuron to the next BI- directional — Are found in the brain and are abundant in embryonic tissue Chemical Synapses — Specialized for the release and reception of neurotransmitters Multiple Sclerosis (MS) Muscular System — An autoimmune disease that mainly affects young adults Interactions of Skeletal Muscles, Their Fascicle — Symptoms include visual disturbances, weakness, loss Arrangement, and Their Lever Systems of muscular control, and urinary incontinence Interactions of Skeletal Muscles in the Body: — Nerve fibers are severed and myelin sheaths in the CNS Muscles may have multiple sites of attachments become > Tendons: attach muscle to bone nonfunctional scleroses > Tendons: pull on periosteum causing bone to move — Shunting and short-circuiting of nerve impulses ocçurs Origin — point of attachment that does not move — Treatments include injections of methylprednisolone Insertion — point of attachment that moves and beta Prime mover — principal muscle involved in an action interferon — Other muscles may be involved in the movement as well. Example: Causes of Multiple Sclerosis Biceps brachii is prime mover for flexion of elbow Scientists do not yet know what triggers the immune system to do this. Most agree that several factors are Synergists and Fixators involved, including: Genetics, Gender, Environmental Triggers Synergists Possibilities include: Viruses* (one that primes the — assist prime mover in accomplishing a movement immune system and another to trigger it), Trauma, Heavy — Example : Brachioradialis and Brachialis during flexion metals (toxicology) of elbow Fixators Neurotransmitter Deficiencies — stabilize insertion points during a movement Norepinephrine deficiency : leads to insatiable hunger, inability to focus or concentrate, Agonists and Antagonists exhaustion and carbohydrate cravings. Agonist Serotonin deficiency : leads to runaway levels of — primarily responsible for an action; also known as the epinephrine and norepinephrine resulting in prime mover depression, anxiety, panic attacks, cravings, irritability, Antagonist aggressiveness and phobias. — muscle that produces the opposite movement of an Dopamine deficiency : is linked with depression, agonist burn-out, lack of motivation, and decreased — Triceps brachii is the antagonist of the biceps brachii libido (or sexual desire) also cravings. — Alternately, the biceps brachii is the antagonist of the Epinephrine deficiency : is seen in cases of adrenal triceps orachiil exhaustion. Patterns of Fascicle Organization Parkinson's Disease Fascicle — A progressive, degenerative disease causing destruction — a bundled group of muscle fibers of nerve cells in — Surrounded by perimysium the basal ganglia of the brain caused by a deficiency of Fascicle arrangement dopamine: — arrangement of fascicles in skeletal muscle — limbs become rigid, fingers have characteristic pill — Influences force generated and range of motion of rolling, movement, and muscle head has to and for movement: Parallel — The patient has a bent position and walks in short, — fascicles arranged in same direction as long axis of shuffling steps: muscle facial expressions become blank with wide open eyes and Fusiform infrequent blinking — parallel arrangement with large muscle belly in the ( parkinson's Mask) middle and narrowing ends — Intelligence is NOT affected Circular : fibers wrap in a circle Convergent: fascicles unite on singular, narrow insertion point Pennate : fascicles blend into tendon in center of muscle Unipennate : fascicles on one side of tendon Bipennate: fascicles on both sides of tendon  Multipennate : muscle branches within muscle — Carpi derived from wrist to resemble many feathers arranged together — Ulnaris due to location on ulna Muscle Bellies Muscle Actions Muscle actions are predictable based on their location — Muscle bellies of fusiform muscles enlarge Lateral side of joint when the muscle contracts — Abduction of limbs — Forms an even larger muscle belly — Lateral flexion of trunk or neck Medial side of joint Naming Skeletal Muscles — Adduction Origins of Skeletal Muscle Names Anterior portion of joint Many skeletal muscles names are derived from Greek — Flexion and Latin root words Posterior portion of joint Names were based on easily observable characteristics of — Extension muscles > Shape, Size comparison, Orientation of fibers, Number Axial Muscles of origins, Action of muscle, Attachment location, Muscles of Facial Expression Grouping of muscle Originate on bones of skull and insert on Characteristics Used to Name Skeletal Muscles skin Muscle shape : named for their resemblance to a shape Orbicularis oculi Muscle size : muscles in a group are sometimes named Orbicularis oris for their size relative to other muscles in the group Occipitofrontalis Location : named for the region where they are located Buccinator Orientation of fibers : orientation of the muscle fibers Zygomaticus major and fascicles is used to describe some muscles Zygomaticus minor Number of origins : number of origins a muscle has can differentiate it from other nearby muscles Muscles That Move the Eyes Action : named for the action the muscle achieves — Originate outside of eye and insert on outer Attachment : attachment location can appear in a surface of eye muscle name (Origin is always first) — Superior and inferior obliques Grouping : some muscles exist in groups — Lateral, medial, inferior, and superior rectus Words that Pertain to Muscle Size Muscles That Move the Lower Jaw Greek and Latin words that describe muscle size include: — Allow for mastication (chewing) Maximus — the largest of a group — Masseter Medius — medium-sized in a group — Temporalis Minimus — the smallest of a group — Pterygoid muscles Brevis — short Longus — long Muscles of the Anterior Neck Major — the largest of two — Assist in swallowing (deglutition) and speech Minor — the smallest of two Suprahyoid muscles Longissimus — the longest > originate above hyoid bone > Digastric, stylohyoid, mylohyoid, geniohyoid Some Muscles are Named for Their Shape Infrahyoid muscles Rhomboid muscles of back resemble the > originate below hyoid bone shape of a rhombus > Omohyoid, sternohyoid, thyrohyoid, sternothyroid Deltoid muscle of the shoulder resembles an upside-down Greek letter Muscles That Move the Tongue delta — Aid in speech, mastication, and swallowing Extrinsic muscles Anatomy of a Muscle Name — originate outside of tongue Biceps brachii — Genioglossus, styloglossus, palatoglossus, — "Bi" = Latin for 2 hyoglossus — "Ceps" derived from Latin for "head" Intrinsic muscles — Brachii refers to the brachium region — originate inside tongue Flexor carpi ulnaris — Flexor derived from action; flexes the wrist Muscles That Move the Head Appendicular Muscles — Head is balanced, moved, and rotated by neck muscles Sternocleidomastoid Shoulder Muscles — Lateral flexion and rotation of head Anterior shoulder muscles Scalenes — Subclavius, pectoralis minor, serratus anterior — Synergists of sternocleidomastoid — Pull scapula forward (protract) Posterior shoulder muscles Muscles of the Posterior Neck and the Back — Trapezius, rhomboid major, rhomboid minor — Lateral flexion, extension, and rotation of — Pull scapula back (retract) head : Splenius capitis, splenius cervicis Extension of vertebral column — Erector spinae group : Iliocostalis, longissimus, spinalis Transversospinalis muscles Quadratus lumborum muscles Anterior Muscles of the Abdomen — External oblique Muscles That Move the Humerus — Internal oblique Pectoralis major and latissimus dorsi — Transversus abdominis — Prime movers of the humerus — Rectus abdominis :Enclosed by rectus sheaths of linea — Convergent muscles alba Muscles that originate on scapula — Deltoid, subscapularis, supraspinatus, infraspinatus, Posterior Muscles of the Abdomen teres major, teres minor, coracobrachialis — Help form posterior wall of the abdomen Rotator cuff — Stabilize body and maintain posture — formed by tendons of subscapularis, supraspinatus, > Psoas major infraspinatus, and teres minor > Iliacus — Give structure and stability to shoulder joint > Quadratus lumborum Muscles That Move the Forearm Muscles of the Thorax — Allow flexion and extension of the elbow, Diaphragm supination, and pronation — divides abdominal and thoracic cavities — Elbow flexion : biceps brachii, brachialis, — Major muscle involved in breathing brachioradialis Intercostal muscles — Elbow extension : triceps brachii, anconeus > External, internal, and innermost — Pronation : pronator teres, pronator quadratus > Located between ribs — Supination : supinator > Assist in breathing The Carpal Tunnel Muscles of the Pelvic Floor Many extrinsic muscles of the hand originate on the Pelvic diaphragm forms base of pelvic cavity humerus — Levator ani Long tendons pass through carpal tunnel to connect > Consists of pubococcygeus and iliococcygeus to hand > Forms anal and urethral sphincters — Retinacula surround tendons at wrist Ischiococcygeus — Flexor retinaculum on palmar surface — Extensor retinaculum on dorsal surface Muscles of the Perineum Perineum Movements of the Forearm, Wrist, and Fingers — space between pubic symphysis and coccyx Forearm: — Urogenital triangle : anterior of perineum — Flexion, extension, pronation, and supination — Includes external genitalia Wrist: Anal triangle — Radial and ulnar deviation, flexion, extension, — posterior perineum pronation, and supination — Includes anus Fingers: — Flexion, extension, hyperextension, abduction, adduction, circumduction Muscles That Move the Wrist, Hand, and Fingers Posterior compartment Superficial muscles — extend thigh, flex knee > Anterior muscles —Hamstrings = Semitendinosus, semimembranosus, — most cause flexion of the hand or fingers biceps femoris — Flexor carpi radialis, palmaris longus, flexor carpi ulnaris, flexor Muscles That Move the Feet digitorum superficialis Anterior compartment > Posterior muscles — dorsiflex foot — most cause extension of the hand or fingers — Tibialis anterior, extensor hallucis longus, extensor — Extensor radialis longus, extensor carpi radialis brevis, digitorum longus extensor — Superior extensor retinaculum and inferior extensor digitorum, extensor digiti minimi, extensor carpi ulnaris retinaculum anchor tendons during contraction Lateral compartment Deep muscles — eversion and plantar flexion of foot > Anterior muscles — Fibularis longus, fibularis brevis — cause flexion of fingers Posterior compartment — Flexor pollicis longus, flexor digitorum profundus — plantar fle