Anatomy sem 1_ week 5-7.docx

Anatomy notes: Anatomy test 2 review 60 questions - skeleton, joints, muscles Integument and bone tissue questions: Differentiate thin and thick skin (thick skin: palm of hands) Explain the relationship between sunlight exposure and vitamin D3 Differentiate between sebaceous gland and sweat gl...

Anatomy notes: Anatomy test 2 review 60 questions - skeleton, joints, muscles Integument and bone tissue questions: Differentiate thin and thick skin (thick skin: palm of hands) Explain the relationship between sunlight exposure and vitamin D3 Differentiate between sebaceous gland and sweat glands Integumentary system: Know the layers (subcutaneous, dermis, epidermis) Know the sweat glands Layers of the epidermis (know where it is, purpose) Stratum corneum Stratum basale Burns (1st, 2nd, 3rd degree) What layers of the skin will be destroyed Sweat glands what glands are where Bones What are building ones, maintaining, etc Osteoblasts Osteocytes Osteoclasts Male vs female pelvis Articulations (ex, ball and socket, saddle joints, etc) Synartthrosis, amphiarthrosis, diarthrosis (synovial joint) Motion words (flexion, extension etc) Know what a virus, bacteria is Muscular system thin/ thick filaments The image on the test: muscular system Full anatomical muscular system Locate major muscle Week 5: Integumentary system Cutaneous membrane: Superficial epithelium, or epidermis Underlying connective tissues of the dermis Made up of two layers: the top is the epidermis, the middle is the dermis, and underneath is the hypodermis Dermis we have accessory structures such as glands, hair, blood, and nerves The subcutaneous layer is a thick layer of adipose tissue, (where fat will be stored when people gain weight) 3 main sections: The top is the epidermis, the thinnest of the three layers (what you would touch if you touched your skin) The middle layer is the dermis, which has a lot of fibers in it that make it stretchy if there are glands, blood vessels, hair, and sensory nerves The subcutaneous layer, or hypodermis The loose connective tissue beneath the dermis Layers of the epidermis: the bottom layer is the stratum basale, these cells are basal or stem cells that are dividing constantly (going through mitosis) (next layer) stratum spinosum – 8-10 layers of keratinocytes (called spinosum because when they are being prepared for microscopic examination they pull apart and shrink looking spiny). Stratum granulosum – cells have stopped dividing and begin making keratin and dehydrate, beginning to become water resistant Stratum lucidum – densely packed flat keratinized dead cells (found only in thick skin) thick skin is found on the palms of hands and soles of feet Stratum corneum – this is the part you touch when you touch your skin – there are 15 to 30 layers of keratinized cells (filled with keratin). These cells are still tightly connected by desmosomes which is why after a sunburn your skin comes off in sheets. It takes about 7-10 days for a cell to move from the stratum basale to the stratum corneum. The dead cells are usually there for another 2 weeks before they are shed or washed away. About 15- 30 days and your skin is completely new Melanocytes: Merkel cells: sensitivity, sense of light touch, pressure, and pain. melanocytes: make melanin, a pigment that colors the skin Melanin: brown yellow-brown or black pigment, even if we are fair-skinned we still have melanocyte-looking cells that produce melanin Freckles: melanin that accumulates in patches in genetically predisposed people Beneficial effects of sunlight on skin: Vitamin D3 Formed by epidermal cells of certain strata Converted from a cholesterol-related when epidermal cells are exposed to UV radiation in sunlight The liver and kidneys convert vitamin D3 into calcitriol a hormone essential for the absorption of calcium and phosphorus Repair of the integument after injury: Skin regeneration occurs because: Skin regenerates easily, it can often repair itself even after extensive damages The regeneration process includes the formation of a scab, granulation tissue, and scar tissue Stem cells of epithelium and connective undergo cell division Replace lost or damaged tissue Four phases of skin regeneration Inflammation phase Migration phase Proliferation phase Scarring phase Burns: First degree: top layer of skin, inflamed, a sun burn Second degree: top layer of skin, blisters Third degree: all of epidermis and dermis is destroyed, including hair and glands, bone/muscle can be seen Week 6: The skeletal system Components include: Bones of the skeleton Cartilages, joints, ligaments Connective tissue that stabilizes or connects bones Functions of the skeletal system: Support Storage of minerals and lipids Blood cell production (blood cells made in red. Yellow = lipids) Protection (ex, skull) Leverage Types of bones: Long (femur) Short (carpal, finger) Irregular (vertebrae) Flat (skull) Types of bone cells: Osteoblasts (construction/building) Produce new bone through a process called ossification Osteoblasts surrounded by bony matrix change into osteocytes osteoBlasts = Building Osteocytes (maintenance) Most abundant cells in the bone Mature cells that maintain bone structure by recycling calcium salts Osteoclasts (demolition/crush) Secrete acid and enzymes that dissolve the matrix Process release minerals through resorption All involved in remodeling Epiphyseal line: At puberty, bone growth accelerates due to increased sex hormone production Osteoblasts produce bone faster than the epiphyseal cartilage can grow and expand (“awkward phase”) Epiphyseal cartilages get narrower until disappear Called epiphyseal closure X-rays of adult bones show the former location of epiphyseal cartilage as the epiphyseal line Bone remodeling process: The remodeling process recycles and renews organic and mineral components of the bone matrix (driven by the need for minerals and the pattern of forces on bones) Osteoblasts continually build matrix Osteocytes maintain the matrix, continually removing and replacing calcium salts Osteoclasts continually remove matrix Normally activity is balanced Skeleton: 206 bones Axial: protects (skull, face, rib cage, hyoid, sternum, vertebrae, sacrum, coccyx) Appendicular: (clavicle, scapula, humerus, radius, ulna, carpal bones, metacarpal bones, phalanges, hip bone, femur, patella, tibia, fibula. Tarsal bones, metatarsal bones, phalanges) Nasal complex: Paranasal sinuses drain into the nasal cavities Nasal septum Formed from ethmoid bone and vomer Separates right and left portions of the nasal cavity The vertebral column: Cervical: C1 to C7 7 vertebrae The secondary curve develops as the infant learns to balance the weight of the head on the vertebrae of the neck (related to tummy time and balance) Thoracic: T1 to T12 12 vertebrae The primary curve provides room for the thoracic organs lumbar: L1 to L5 5 vertebrae The secondary curve balances the weight of the trunk over the lower limbs, The curve develops with the ability to stand (related to being able to stand) Sacral: The primary curve provides room for various abdominopelvic organs Coccygeal “Breakfast at 7, lunch at 12, dinner at 5”’ Thoracic cage: Top to bottom of thoracic cage: Jugular notch Clavicular articulation Sternum (manubrium, body, xiphoid process) Costal cartilages Vertebrochondral ribs (ribs 8-10) Floating ribs (ribs 11-12) True ribs (ribs 1-7) -> attached to sternum directly False ribs (ribs 8-12) -> not attached directly to the sternum Carpal bones of the wrist: eight bones in two rows Classified as short bones Freely movable joints, or diarthrosis: Synovial joints are the most common joints With a wide range of motion Ends of bones covered with articular cartilage Joint surrounded with a fibrous joint capsule Inner surfaces lined with the synovial membrane Synovial fluid within reduces friction lubricates the surfaces, nourishes cartilage Articulations: Ball and socket: head of humerus -> scapula Hinge joint: humerus -> ulna Pivot joint: radius -> ulna Plane joint: carpal bones Saddle joint: carpal bones Condylar joint: metacarpal bones Week 7: Muscular system: Five skeletal muscle functions: Move the skeleton Pull on the tendons that then move bones Muscles produce skeletal movement by attaching to bones and using bones as levers to move your body around Maintain posture and body position Support soft tissues Abdominal wall and pelvic cavity floor composed of skeletal muscle No bones in abdominal, shiels internal organs from injury Guard entrances and exits Encircle openings of digestive and urinary tracts There are sphincters, and circles of muscles that guard entrances and exits Ex, digestive and urinary tract Maintain body temperature Muscle contracts generate heat The more active we are the more our muscles work and they give off heat as a byproduct Skeletal muscle is a bundle of skeletal muscle fibers wrapped in connective tissue layers Epimysium: separates the muscles from the surrounding tissues and organs is made up of collagen fibers Perimysium: This is a fibrous layer that divides muscle into bundles of fibers called muscle fascicles (think roast beef), the perimysium contains collagen and elastin fibers, blood vessels and nerves Endomysium: delicate connective tissue surrounding individual muscle fibers Collagen fibers of connective tissue layers extending beyond the muscle at the end are tendons (attach muscle to bone) Aponeurosis: attach muscle to broader areas (individual muscle cell) *need to know* Sarcolemma: cell membrane, the cell is filled with sarcoplasm Myofibrils: protein tubes that fill the cell and they have a banded appearance Sarcoplasmic reticulum: the myofibrils are covered with membranous sacs called sarcoplasmic reticulum (modified ER of the muscle) (coloured in blue on the picture) Transverse tubules (T Tubules) (are the yellow tubes in the picture) The bottom half of the picture shows thick and thin filaments (responsible for muscle contraction) Thick filaments (myosin) Thin filaments (actin) The meeting of thick and thin filaments is called sarcomere Sarcomere organization: Thick filaments (myosin) Thin filaments (actin) Troponin blocks the active site (right under each troponin is an active site or binding site where something wants to bind) Troponin is blocking the active site Actin moves during a contraction site Myosin connects during a contraction site (stays put) 3. Ach is a neurotransmitter or chemical messenger. It can go into the cleft and send messages. Acetylcholine release at a neuromuscular junction is stimulated by the arrival of the action potential. 4. Ach spills into the cleft and binds into receptors on the muscle cell membrane. Sodium rushing into the cell reforms the action potential. Acetylcholine receptor binding on the motor end plate triggers sodium to enter the muscle cell. 5. Acetylcholinesterase is an enzyme that breaks down Ach in the synaptic cleft. Motor unit: A single motor neuron and all the muscle fibers it controls Muscle fibers of each motor unit intermingle with fibers from other motor units Size of the motor unit indicates the degree of control Gross movements such as muscle in the leg Motor units contain up to 2000 muscle fibers per neuron Precise movements such as muscles of the eye Motor units contain very few fibers per neuron Automaticity: cardiac muscle tissue can contract without neural stimulation Pacemaker cells: specialized cardiac muscle cells, determine the timing of contraction Longer contractions (about 10x longer than skeletal muscle) Tetanus (sustained contraction) cannot occur Extracellular calcium ions Action potential increases permeability of cardiac muscle cell plasma membrane to calcium Allows entry of additional calcium through plasma membrane Cardiac muscle cells rely on aerobic metabolism Smooth muscle cells: Similar in size to cardiac muscle cells Spindle-shaped and have a single nucleus Found in the walls of most organs, in the form of sheets, bundles, or sheaths Smooth muscle lacks myofibrils, sarcomeres, and striations Thick filaments are scattered throughout sarcoplasm Thin filaments are anchored to the sarcolemma Anchoring sites not in a straight line Contraction casues twisting like a corkscrew Adjacent cells bound together Contractile force transmitted throughout tissue Differences: Contractions triggered differently Most of calcium for trigger enters from extracellular fluid Contract over greater range of lengths Actin and myosin not rigidly organzied Function involuntarily Can respond to hormones or pacesetter cells Can also response to motor neurons ATP is energy source for muscle contraction: Muscle contraction requires large amounts of energy in the form of ATP Resting muscle fiber contains only enough energy reserves to maintain contraction until more ATP is generated During contraction, muscle generates ATP at the same rate as it is used During contraction, each cross-bridge breaks down A T P into A D P and a phosphate group Energy stored in C P used to recharge A D P back to A T P Reaction regulated by enzyme, creatine phosphokinase (C P K or C K) Energy reserves exhausted in about 15 seconds A T P must then be generated by different means Examples: anaerobic glycolysis and aerobic metabolism A T P transfers energy from one area to another A T P does not store energy long-term At rest, muscle fiber produces more A T P than needed Excess A T P transfers energy to creatine forming creatine phosphate (C P) *should know for test* External Oblique Rectus abdomins Trapezius Sternocleiomastioud Biceps Triceps Deltoids Gluteus maximus Vastus lateralis Four effects of aging on skeletal muscle: Skeletal muscle fibers become smaller in diameter Skeletal muscles become less elastic Increasing fibrous tissue (fibrosis) makes muscle less flexible Tolerance for exercise decreases Tendency to tire quickly Decrease in thermoregulation Ability to recover from injury Exercise engages multiple systems: Muscular system Active muscles consume oxygen and generate CO2 and heat Cardiovascular system Increases heart rate and speeds up delivery of oxygen Respiratory system Increases rate and depth of respiration Integumentary system Dilation of blood vessels and sweating combine to increase cooling Nervous and endocrine systems Control heart rate, respiratory rate, and release of stored energy