A&P- Science Olympiad

The integumentary system consists of the skin, hair, nails, the subcutaneous tissue below the skin, and assorted glands. [Functions:protection/regulation of temperature/sensory perception/regulate water loss/chemical synthesis][Physical barriers:waterproofing keratinized skin/Certain waterproofs & protects/][Biological barriers:Langerhan’s cells,Macrophages,DNA][Temp Reg:sweat/constriction when cold][Cutaneous sensations:Messiner’s corpuscles:light touch/Merkel discs:light touch/Pascinian receptors:pressure ducts/Hair root plexus:sensations from movement of hairs/Hair follicle receptors:mvmt across surface of skin/Bare nerve endings:painful stimuli][Excretion/Absrp:elimination of nitrogen waste/waterloss regul.][Metabolic functions:synthesis of vitaminD/chemical conversion of substances/blood reservior][Types of membranes: thin sheet structures that protect][Serous membrane:lines cavities/secrete watery fluid][Mucous membrane:lines cavities & tubes that open to the outside][Synovial membranes:form inner lining of cavities/secrete thick fluid][Cutaneous membrane:skin][Skin characteristics:covers body/16% of body mass/epidermis + dermis][Thin:lacks strtum lucidium][Thick:hairless/palms,soles/strtm lucidium][Str. Corn: sheds countinouosly][Str. lucid:thick skin ONLY][Str. gran: keratinocytes undergo apoptosis][Str. spin:Cell division/stretch&flexibility]Str basale:new cells][Epidermis growth:new cells/goes through apoptosis/sheds][Dermis:second layer/mainly connective tissue/vessels,glands,follicles are embeded/2LAYERS-Papillary:superfical portion of dermis/Recticular:deeper portion/provides strength & elasticity][Hypodermis:lies below dermis/conective+adipose][Skin apperances:White skin:apprs pink due to blood/Albinism:inherited trait-lacking color][Cyanotic:blue][Jaundice:yellow,build up of bilirubin][Erythema:red/capillary damage due to skin injury][Pallor:paleness/emotional state/low blood pressure][Bronzing:Addison’s disease, adrenal cortex][Bruising:escaped blood as clottedhemtomas(lack of vit.D/hemophilia][Leathery skin: overexposure clumping of elastin fibers-depressed immune system][Photosensitivity: to antibiotics/antihistamines][Skin color:genes/envrnt/volume of blood][Skin pigments:melanin/Carotene:yellow/orange/Hemoglobin][Envrnt:UV/tan][Skin markings:friction ridges:markings on fingertips/Flexion lines:on flexor surfaces(digits/palms/wrists)/Freckles:flat melanized patches/Moles:elevated patch of melanzied skin][Aging:stem cell activity declines/thinner hair/blood supply decline/incres. dryness][Derivatives of skin:embroyonic devplt. thouds of epidermal cells from the strm basale push doen into dermis][Skin Receptors: Light touch:Meissner’s corpuscles are enclosed in a capsule of connective tissue/Paccinian corpuscules:sense pressure and vibration changes deep in your skin/Pain:skin receptors register pain][Temp:Cold receptors start to perceive cold sensations when the surface of the skin drops below 95/Hot receptors start to perceive hot sensations when the surface of the skin rises above 86F and are most stimulated at 113F/Thermoreceptors are found all over the body, but cold receptors are found in greater density than heat receptors – most of the time our environment is colder than our body temperature][Hair: Shaft:portion of hair that projects from skin surface/Root:portion of hair deep to the shaft penetrating the dermis-3 layers:medulla: contains pigment granules and air spaces/cortex: middle layer in dark hair contains pigment in gray or white hair contains air bubbles/cuticle: outer layer/Base:Bulb: houses the papilla which contains the blood vessels that nourishes the growing hair follicle/Matrix: responsible for hair growth and produces new hair/Arrector pili: smooth muscle-Extends from the dermis to the side of hair follicle-Arrector pili muscles contract and pulls hair straight causing goose bumps/Hair root plexus – dendrites of neurons which are sensitive to touch][Hair growth:Anagen – Growth Phase/Catagen – Transitional Phase/Telogen – Resting Phase][Hair function:Hair on the head protects scalp from injury and sunlight/Help in sensing light touch due to the touch receptors associated with the hair root plexuses][Skin glands:Sudoriferous – sweat glands (sudori = sweat) (ferous = bearing)/Eccrine sweat glands:Secretes cooling sweat/Appocrine sweat glands:Stimulated during emotional stress/excitement/viscous/Sebaceous -oil glands:Absent in the palms and soles/Secrete an oily substance called sebum. which lubricates the hair and skin/Ceruminous – modified sweat glands of the external ear that produce ear wax:Open directly onto the surface of the external auditory canal (ear canal) or into ducts of sebaceous glands][Nails:Made of tightly packed, hard, keratinized epidermal cells/Nail body: portion of the nail that is visible/Free edge: part that extends past the distal end of the digit/Nail root: portion buried in a fold of skin/Lunula:means little moon/Eponychium or cuticle: narrow band of epidermis Growth of nails is in the nail matrix][Homeostatsis imbalance:Skin Imbalances – The skin can develop >1000 different ailments. the most common skin disorders result from allergies or infections less common are burns and skin cancers/Skin lesions – any measurable variation from normal structure of the skin/Elevated lesions – cast a shadow outside the edges as warts, plaque, blister/Flat lesions – do not cast a shadow as a scab, elevated lesion with pus, hive/Depressed lesions – cast a shadow within their edges as lacerations, ulcers, fissures/Infections-Viral – eg. cold sores, herpes simplex especially around lips and oral mucosa/Warts – benign neoplasms caused by papillomavirus (HPV)/Fungal – eg. athletes foot, Tinea/Bacterial- eg. boils and carbuncles inflammation of hair follicle and sebaceous glands especially on face or dorsal side of neck, impetigo Streptococcus infection/Contact dermatitis is a condition in which the skin becomes red, sore, or inflamed after direct contact with a substance. There are two kinds of contact dermatitis: irritant or allergies-Irritant dermatitis is the most common type. It’s caused by contact with acids, alkaline materials such as soaps and detergents, fabric softeners, solvents, or other chemicals. The reaction usually looks like a burn/Allergic contact dermatitis is caused by exposure to a substance or material to which you have become extra sensitive or allergic][Genetic disorders:Psoriasis/Vitiligo – an autoimmune pigmentation disorder where melanocytes in the epidermis are destroyed][Burns:1st degree burns-skin is inflamed, red – surface layer of skin is shed/2nd-degree burns-deeper injury – blisters form as fluid builds up beneath outer layers of epidermis/3rd degree burns full thickness of skin is destroyed -sometimes even subcutaneous tissues results in ulceratin wounds/A fourth- degree burn additionally involves injury to deeper tissues, such as muscle or bone][Rule of 9’s:extend of burn damage estimated by head, arms ~9% of skin surface-front and back of torso, each leg ~18% of skin surface-groin ~1% of skin surface][Skin cancer:basal cell carcinoma(less malignant)/sq. cell carcinoma(20% of all)/malignant cell carcinoma(rare 1%).
muscular system:{Muscle function:Stabilizing joints/Maintaining posture/Producing movement/Moving substances within the body/Stabilizing body position and regulating organ volume/Producing heat– muscle contraction generates 85% of the body’s heat][Characteristics of tissue:Excitability- receive and respond to stimuli/Contractility- ability to shorten and thicken/Extensibility- ability to stretch/Elasticity- ability to return to its original shape after contraction or extension][Skeletal Muscle:Each muscle is a discrete organ composed of muscle tissue, blood vessels, nerve fibers, and connective tissue/Each muscle has thousands of muscle fibers in a bundle running from origin to insertion bound together by connective tissue through which run blood vessels and nerves/The three connective tissue wrappings are:Epimysium – an overcoat of dense regular CT that surrounds the entire muscle/Perimysium – fibrous CT that surrounds groups of muscle fibers called fascicles/Endomysium – fine sheath of CT composed of reticular fibers surrounding each muscle/A sarcomere consists of the array of thick and thin filaments between two Z disks][A motor unit is a motor neuron&all muscle fibers it supplies][Contraction:cross bridge attachment-myosin pivots & pulls actin toward mline][Muscle fatigue:the muscle is in a state of physiological inability to contract/Lactic acid accumulates in the muscle][Oxygen  debt:Vigorous exercise causes dramatic changes in muscle chemistry][Muscle & tendon injuries:Strains:injuries from overexertion or trauma which involve stretching or tearing of muscle fibers. They often are accompanied by pain and inflammation of the muscle and tendon. If the injury is near a joint and involves a ligament, it is called a sprain/Cramps – painful muscle spasms or involuntary twitches/Stress-induced muscle tension – may cause back pain and headaches][Muscular disorders:Poliomyelitis – viral infection of the nerves that control skeletal muscle movement/Muscular Dystrophies – most common caused by mutation of gene for the protein dystrophin which helps in attaching and organizing the filaments in the sacromere/Myasthenia gravis – autoimmune disease affecting the neuromuscular junction/Tetanus – a serious bacterial disease that affects your nervous system, leading to painful muscle contractions, particularly of your jaw and neck muscles][Homestatic imbalance: with age connective tissue increases & muscle fibers decrease/muscles become weaker][Exercise & muscular system: helps muscles become effective & efficient]
skeletal system: Skeletal and Muscular systems works together to allow movement/Bone attaches to bone via ligaments/Muscle attaches to bone via tendons/Skeletal muscles produce movement by bending the skeleton at movable joints. Muscles work in antagonistic pairs/Skeleton provides structure of body and muscles allow skeleton mobility – pull by contraction of muscle][Functions:Support & shape to body-Protection of internal organs/Movement in union with muscles/Storage of minerals (calcium,phosphorus) & lipids/Blood cell production][Skeleton: 206 bones-Axial skeleton: (80 bones) in skull, vertebrae, ribs, sternum, hyoid bone/Appendicular Skeleton:(126 bones)- upper & lower extremities plus two girdles/Half of bones in hands & feet][Types of bone:Long bones: longer than they are wide; shaft & 2 ends (e.g.: bones of arms & legs, except wrist, ankle & patella)/Short bones: roughly cube-shaped (e.g.: ankle & wrist bones)/Sesamoid bones: short bones within tendons (e.g.: patella)/Flat bones: thin, flat & often curved (e.g.,: sternum, scapulae, ribs & most skull bones)/Irregular bones: odd shapes; don’t fit into other classes (e.g.: hip bones & vertebrae)][Types of vertebrae:Cevical (7)- transverse foramina, bifid spinous processesvertebral prominens o Atlas- 1st; supports head/Axis- 2nd; pivots to turn head/Thoracic (12)- long spinous processes, rib facets/Lumbar (5)- large bodies thick short spinous processes][Types of synovial joints: Ball & Socket – allows for complete range of motion/Pivot – one bone pivots in the arch of another Example: Axis/Atlas, and proximal radioulnar joint/Saddle – two directional movement between thumb and trapezium carpel/Hinge – like door hinge – bending & extending Example: elbow, knee, finger joints/Ellipsoid (Condyloid) – side to side and back & forth Example – radius end into carpal bones/Plane or Gliding – least moveable – side to side only Examples: intercarpal & intertarsa joints, between vertebrae][Cartilage+Types:Mostly water; no blood vessels or nerves-Tough, resilient/New cartilage forms from chondroblasts/Heal poorly/Types: Hyaline Cartilages: fine collagen fiber matrix- most abundant type- found in articular (movable joint) cartilages, costal cartilages (connect ribs tosternum), respiratory cartilages (in larynx & upper respiratory passageways) & nasal cartilages/Elastic Cartilages: similar to hyaline cartilage, more elastic fibers (very flexible) – found in external ear & epiglottis (larynx covering)/Fibrocartilage: rows of chondrocytes with thick collagen fibers; highly compressible with great tensile strength- found in menisci of knee, intervertebral discs & pubic symphysis][Long bone: Compact:The hard outer layer of bones is composed of compact bone tissue, so-called due to its minimal gaps and spaces/This tissue gives bones their smooth, white, and solid appearance, and accounts for 80% of the total bone mass of an adult skeleton/Compact bone may also be referred to as dense bone or cortical bone/Spomgy: Filling the interior of the organ is the spongy bone tissue which is composed of a network of rod- and plate-like elements that make the overall organ lighter and allowing room for blood vessels and marrow/Spongy bone accounts for the remaining 20% of total bone mass, but has nearly ten times the surface area of compact bone][Bone composure: Osteoblasts – bone forming cells synthesize and secrete unmineralized ground substance and are found in areas of high metabolism within the bone/Osteocytes – mature bone cells made from osteoblasts that have made bone tissue around themselves.These cells maintain healthy bone tissue by secreting enzymes and controlling the bone mineral content;they also control the calcium release from the bone tissue to the blood/Bone lining cells – made from osteoblasts along the surface of most bones in an adult. Bone-lining cell are thought to regulate the movement of calcium and phosphate into and out of the bone/Osteogenic cells – respond to traumas, such as fractures, by giving rise to bone-forming cells and bone destroying cells/Osteoclasts – bone absorbing cell – large cells that break down bone tissue – important to growth,healing, remodeling][Marrow:The formation of blood cells, termed hematopoiesis, takes place mainly in the red marrow of the bones/In infants, red marrow is found in the bone cavities. With age, it is largely replaced by yellow marrow for fat storage./In adults, red marrow is limited to the spongy bone in the skull, ribs, sternum, clavicles, vertebrae and pelvis. Red marrow functions in the formation of red blood cells, white blood cells and blood platelets][Bone structure: Haversian system, or osteon – the structural unit of compact bone/Lamella – weight-bearing, column-like matrix tubes composed mainly of collagen/Haversian, or central canal – central channel containing blood vessels and nerves/Volkmann’s canals – channels lying at right angles to the central canal, connecting blood and nerve supply of the periosteum to that of the Haversian canal/Osteocytes – mature bone cells/Lacunae – small cavities in bone that contain osteocytes/Canaliculi – hairlike canals that connect lacunae to each other and the central canal][Structure:Diaphysis-Tubular shaft that forms the axis of long bones-Composed of compact bone that surrounds the medullary cavity/Epiphyses-Expanded ends of long bones/Exterior is compact bone, and the interior is spongy bone][Bone membranes: Periosteum – double-layered protective membrane/Endosteum – delicate membrane covering internal surfaces of bone][Bone markings:Bulges, depressions, and holes that serve as:Sites of attachment for muscles, ligaments, and tendons-Joint surfaces-Conduits for blood vessels and nerves][Projections where muscles, tendons and ligaments attach-Tubercle – small rounded projection/Tuberosity – rounded projection/Crest – narrow, prominent ridge of bone/Trochanter – large, blunt, irregular surface/Line – narrow ridge of bone/Epicondyle – raised area above a condyle/Spine – sharp, slender projection/Process – any bony prominence][Bone fracture termin:Nondisplaced – bone ends retain their normal position/Displaced – bone ends are out of normal alignment/Complete – bone in broken all the way through/Incomplete – bone is not broken all the way through/Compound (open) – bone ends penetrate the skin/Simple (closed) – bone ends do not penetrate the skin][Common fractures:Linear – the fracture is parallel to the long axis of the bone/Transverse – the fracture is perpendicular to the long axis of the bone/Oblique – diagonal breaks across the bone/Comminuted – bone fragments into three or more pieces; common in the elderly/Spiral – ragged break when bone is excessively twisted; common sports injury/Avulsion – pieces of the bone have been pulled apart/Impacted – opposite of avulsion fractures – a piece of bone is pushed down into another piece of bone/Fissure – cracks in the bone/Depressed – broken bone portion pressed inward; typical skull fracture/Greenstick – incomplete fracture – one side of the bone breaks and the other side bends; common in children/Compression – bone is crushed; common in porous bones/Epiphyseal – epiphysis separates from diaphysis along epiphyseal line; occurs where cartilage cells are dying][Bone repair: Injury – broken blood vessels, hematoma-Invasion of blood vessels & generalized cells (2-3 days)-Fibroblasts develop (1 week)-Chondroblasts develop-Callus forms (4 weeks)-Remodeling with osteoclasts (8 weeks)][Skeletal disorders: Spinal Stenosis-narrowing of the spinal column/Achondroplasia-Defect in the formation of cartilate at the epiphysis of long bones (dwarfing)/Juvenile Rheumatoid Arthritis-chronic inflammatory diseases involving the joints or other organs in children under 16/Ankylosing spondylitis-immobility of a joint in the spine/Osteosarcoma-malignant sarcoma of bone/Osteoporosis-Loss of bone mass that occurs throughout the skeleton. Predisposes people to fractures/Disc Herniation-Rupture of the soft tissue that separates two vertebral bones into the spinal canal/Scoliosisa lateral curvature of the spine][Inflammatory/Degenerative Dis:Bursitis-An inflammation of a bursa, usually caused by a blow or friction/Tendonitis-Inflammation of tendon sheaths typically caused by overuse/Arthritis-More than 100 different types of inflammatory or degenerative diseases that damage the joints/Osteoarthritis (OA)-Most common chronic arthritis; often called “wear-and-tear” arthritis/Rheumatoid Arthritis (RA)-Chronic, inflammatory, autoimmune disease of unknown cause, with an insidious onset.