Study guide exam 2 a&p - Lecture notes 4-7 PDF

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study guide for second exam with professor leonard...

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BONUS: Connective Tissue

 What are the shapes & arrangements of epithelial tissues; what is /are the structure vs function relationships (squamous is found where diffusion is necessary ; stratified epithelium where you need defense & protection like the skin) Shapes: squamous, cuboidal, or columnar Function: - squamous- found where diffusion necessary - Stratified epithelium- where you need defense and protection  What are the types of Connective tissue (cells that are found there and fibers that make it up); functions of the different types (types of cartilage & functions; types of muscle & functions; types of bone) – TABLE 4.4 – 4.6 ;  Types: loose connective tissue, dense connective tissue, bone, cartilage, blood and lymph.

  what is the ground substance; what are the ingredients etc . -

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substance in the extracellular space that contains all components of the extracellular matrix (ECM) except for fibrous materials such as collagen and elastin.

what are the cells of cartilage called; what are the types of cartilage? Types of cartilage:

Hyaline - most common, found in the ribs, nose, larynx, trachea. Is a precursor of bone. 2. Fibro- is found in invertebral discs, joint capsules, ligaments 3. Elastic - is found in the external ear, epiglottis and larynx.

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Joints: 

Know the 3 types of joints (fibrous, cartilaginous, & synovial; and what characterizes each; suture joint is an example of which? Pubic symphysis is an example of which ? Types of joints: 1. fibrous- dense fibrous CT, ex structure 2. cartilaginous- Synchondrosis – hyaline cartilage; no movement, ex pubic symphysis 3. synovial- Articular cartilage on ends of long bones and a synovial cavity between articulating bones surrounded by accessory ligaments; freely moveable

 The components of a synovial joint; which cells produce synovial fluid (cells found in the synovial membrane); AND an example of where hyaline cartilage is found (articular cartilage) characteristics of the knee joint

pads of fibrocartilage that lie between the articular surfaces fo the bones – these are the articular discs (menisci).

 General function of synarthrosis & diarthrosis (synovial joint , articular cartilage, meniscus, synovial membrane); - synarthrosis -immovable joint - diarthrosis- freely movable

 General characteristics of fibrous joints (pubic symphysis); a type or example of fibrocartilage joint  The role of tendon sheaths and bursae (between tendons or bones) IN general ; where are they located ? Fibrous joints- strong connections between bones Bursae reduce friction  Joint motions (flexion, extension, aBduction, aDduction

Bone: Chapter 6 1.

General structural units of osteon (canaliculi, lamellae, lacunae, central canal etc.) o central canal running longitudinally thru bone and they connect adjacent osteons (communicate via gap junctions) o concentric lamellae – rings of calcified matrix o lacunae – small spaces containing osteocytes o canaliculi – small channels radiating in all directions form lacunae filled with fluid and processes of osteocytes

2.

Know Functions of bone AND know the cells of bone and their functions ; know their differentiation (from Osteoprogenitor to osteoblast to osteocytes)

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Functions of bone: 1. Support 2. Protect organs 3. Body movement 4. Mineral homeostasis- store and release calcium and phosphates 5. Homeopoiesis- blood cell production 6. Store triglycerides in adipose cells of yellow marrow  Cells of Bone: a)

Osteoprogenitor cell - are stem cell/undergo mitosis; they develop into OB; found in periosteum (inner layer ) & endosteum & in canals of blood vessels b) Osteoblast - are cells bone-building ; they are non- mitotic; they secrete collagen and matrix & initiate calcification c) Osteocytes - are mature bone cells/non-mitotic; derived from osteoblast; they lie in lacunae; do not secrete matrix; maintain activities of bone, i.e. (exchange nutrients, waste) d) osteoclast - are found on bone surface; they are derived from many monocytes (WBC); functions in bone destruction/remodeling/repair by releasing powerful lysosomal enzymes (from a “ruffled border”) that digest protein – termed resorption which is part of normal development, growth, maintenance and repair.

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Difference in structure of spongy vs compact bone in structure (true osteons are in compact bone) and location within the bone 1.Compact bone is also called cortical bone while spongy bone is also called cancellous bone. 2.Compact bones are made of osteons while spongy bones are made of trabeculae. 3.Compact bones are tough and heavy while spongy bones are light. 4.Compact bones fill the outer layer of most of the bones while spongy bones fill the inner layer of the bones

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Know anatomy of LONG bone including periosteum and endosteum & marrow cavity - Long bones grow primarily by elongation of the diaphysis (the central shaft), with an epiphysis at each end of the growing bone. The ends of epiphyses are covered with hyaline cartilage (articular cartilage). At the cessation of growth, the epiphyses fuse to the diaphysis, thus obliterating the intermediate area known as the epiphyseal plate or growth plate. The long bones in the body are as follows: Diaphysis – long cylindrical shaft, main portion of bone Epiphyses – distal/ proximal ends of bones Metaphysis – region joining diaphysis and epiphysis . In a growing bone, each metaphysis contains an epiphyseal (growth) plate, a layer of hyaline cartilage that allows the diaphysis of the bone to grow in. When a bone ceases to grow in length at about ages 14–24, the cartilage in the epiphyseal plate is replaced by bone; the resulting bony structure is known as the epiphyseal line. Articular Cartilage – Hyaline Cartilage covering part of epiphysis where bone forms joint with another bone - reduces friction and absorbs shock at freely movable joints. Because articular cartilage lacks a perichondrium and lacks blood vessels, repair of damage is limited.

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6) Periosteum – outer layer – dense, irregular connective tissue Inner layer – osteogenic layer allows bone to grow in thickness, not length also protects the bone, assists in fracture repair, helps nourish bone tissue, and serves as an attachment point for ligaments and tendons. 7) Medullary cavity – marrow cavity medullary cavity, stores red and yellow (in adults) bone marrow 8) Endosteum – thin membrane lining bone surface of medullary cavity; contains progenitor cells and osteoclasts

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Materials of bone (protein & salts); process of mineralization (calcification); what is (it is the minerals of bone!)

Bone materials: 25% H2O/ 25% protein/ 50% crystallized mineral salt; the proteins component is Collagen provides strength + elasticity - the inorganic, mineral salts part is (Ca phosphate & Ca+ carbonate), termed hydroxyapatite & there are smaller amounts of fluoride & sulfate (provide hardness) Calcification: 2. Process: Calcification: OB Osteocytes and now live in lacunae, OC stop secreting matrix & Matrix calcifies - The salts crystallize (CALCIFICATION) around the collagen fibers and the tissue hardens (MINERALIZATION).

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Mineralization occurs ONLY in the presence of collagen fibers and the mineral salts begin to crystallize in the microscopic spaces between collagen fibers, and after the spaces are filled, crystals accumulate around collagen Mineralization of salts occurs only in presence of collagen and surrounds collagen before it hardens.  These salts include calcium & phosphate from the blood.  The salts crystallize around the collagen b/c the surrounding tissue is supersaturated with the salts  Most tissues have inhibitors that prevent crystals from forming in a supersaturated environment. OB neutralize these inhibitors & allow the salts to precipitate.  Mineral salts accumulate as hydroxyapatite seed crystals in the spaces between collagen fibers 6.

IO & EO in general; (ie: know that the IO does NOT involve the formation of a cartilage model) differences between these processes of ossification; and which bones develop by which process

a. Intramembranous Ossification: flat fetus skull bones, mandible, and clavicle formed this way 1. Development of the center of ossification: - Mesenchymal cells in loose CT condense and differentiate into Osteoprogenitor cells which differentiate into OB (secrete bone matrix (collagen)) 2.

Calcification: - OB form Osteocytes and now live in lacunae, OC stop secreting matrix & Matrix calcifies

3.

Formation of Trabeculae: - Pattern formed is trabecular- open lattace of (spongy bone); blood vessels innervate spaces between trabeculae

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Development of periosteum: - Outer mesenchyme develops into 2-layered periosteum; eventually a thin layer of compact bone replaces the surface layers of spongy bone, but the spongy bone remains in the center; much of the new bone is remodeled as the bone is transformed into its adult size and shape b. Endochondral Ossification: Development of a cartilage model 1. Cartilage cells condense into the shape of future long bones (perichrondrium) 2. mesenchyme differentiate into chondroblasts and produce matrix and the model is hyaline cartilage Growth of Cartilage model 1. Chondroblasts become chondrocytes and the model grows by cell division; Cartilage cells divide (internally = interstitial growth (length) & externally = appositional growth (thickness) 2. Cartilage in midregion – hypertrophy and die and calcifies Nutrient artery invades via nutrient foramen into dying midregion, the perichondrium. This stimulates perichondrioum periosteiom, which lays down compact bone at periosteal bone collar Development of the Primary Ossification Center a) primary ossification center- midregion of long bone; it is induced by nutrient artery invasion; a region where bone replaces cartilage b) the calcifying cartilage model stimulates osteogenic cells in the perichondrium to differentiate into OB & once this happens the perichondrium is now the perosteum c) the capillaries induce growth of the primary ossification center , a region where bone replaces cartilage – OB deposit bone matrix over the remants of calcified cartilage forming spongy bone d) ossification center enlarges towards the ends of bone; OC break down the new spongy bone and marrow fills cavity; Primary ossification proceeds inward from external surface Development of the Secondary Ossification Center a) the diaphysis becomes compact bone with a core of red marrow – medullary cavity b) capillaries enter the epiphysis to form secondary ossification center around time of birth

c) bone formation is similar to to 10 ossification EXCEPT that: spongy bone fills cavity not marrow cavity & hyaline cartilage remains at epiphysical plate Formation of the aArticular Cartilage and Epiphyseal Plate a) hyaline cartilage covers epiphysis &becomes articular cartilage b) prior to adulthood, epiphyseal cartilage remains as the epiphyseal plate – responsible for growth of long bones 5.

What is Appositional vs longitudinal growth- how is each performed Appositional growth (Thickness): a) Appositional bone growth increases thickness of shaft b) At bone surface, perosteal cells differentiate into OB that secrete collagen and bone matrix in which they get trapped; a ridge is formed around the periostal vessel and eventually a groove is created for the periosteal vessel. c) OB in the endosteum deposit bone matrix, forming new concentric lamellae which proceed inward toward the enclosed vessel. In this way, the tunnel fills in, and a new osteon is created. d) As an osteon is forming, OB under the periosteum deposit new outer circumferential lamellae further increasing the thickness of bone. * As new bone is being deposited in the outer surface of bone the bone tissue lining the medullary cavity is destroyed by OC in the endosteum so that the medullary cavity enlarges as the bone increases in diameter. Length a) Bone grows from epiphysical plate (EO) (cartilage) dividing during early life & the Cartilage cells divide by mitosis at plate (epiphyseal) b) There are 4 zones of growth Zone of resting cartilage: they are resting chondrocytes Zone of proliferating cartilage: chondrocytes stacked like coins; actively divide and replace those at the diaphyseal side of the epiphyseal plate Zone of hypertropic cartilage: chondrocytes are dying Zone calcified cartilage: dead chondrocytes with calcified matrix around it; invaded by OB & capillaries that lay down bone matrix c) as bone grows, chonddrocytes proliferate on the epiphyseal side of the plate, new cells cover older ones which are destroyed by calcification. The cartilage is replaced by bone on the diaphyseal side of the plate. In this way the thickness of the plate remains constant, but the bone on the diaphyseal side increases in length d) This occurs so that plate remains constant till teen yr; If damage to plate as children - bones grow to different size e) Gradually plate cartilage stops mitosis and bone forms on plate. Clavicle is last bone to stop; female growth stops before male 6.

Role of hGF & PTH & Calcitonin in bone formation/maintenance; role of calcitonin & pTH in bone growth and repair & Ca+ homeostasis- pTH stimulates the activity of osteoclast cells to relase Ca+ to the blood)!    

HGF promotes bone growth by stimulating IGF (liver & bone) IGF promotes bone growth by promoting cell division at the plate and periosteum & enhances protein synthesis calcitonin – produced by thyroid parafollicular cells; it inhibits activity of OC , speeds Ca+ deposition into bone by OB cells; secreted when blood Ca+ levels rise above normal; promotes bone formation pTH - pd by parathyroid gland ; increase blood Ca+ by simulating OC & bone re-absorption & by telling kidney to retain Ca+ , and by stimulating formation of calcitriol a hormone that promotes absorption of Ca+ from the GI tract helping to elevate blood Ca+

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Fracture repair ( in general ) : and several of the fractures (open, impacted, greenstick, Colles) a) a fracture is a break in bone & are given common names  open fracture = broken bone ends protrudes thru skin  comminuted fracture = bone splinter at site of impact  Colles fracture = occurs at distal end of lateral radius in which distal fragment is displaced  Greenstick fracture = partial fracture of one side of bone and other side is bent (occurs only in children whose bones not fully ossified)  Impacted fracture = one end of bone is forcefully driven into interior of another end  Stress fracture = is a series of microscopic fissures in bone that forms without visible break. In adults, results from repeated strenuous activities like running, jumping etc. Can result from osteoporosis (25% of these are in tibia) b) Bone repair process occurs in steps:  Formation of fracture hematoma = Broken vessels arrive at site in 1-10 hrs. and form clot; swelling & inflammation occurs ; macrophages & OC remove dead cells and tissue; stage last several weeks.  Fibrocartilage callus forms = (3 weeks) - granulation tissue deposited during previous stage begins to lay down collagen (Fb cells) which connect broken ends of bone; osteogenic cells develop into chondroblasts that produce fibrocartilage callus; stage last 3 weeks  Bony callus formation=- progenitor cells in CT develop into OB that produce spongy bone and in time all the fibrocartilage becomes spongy bone and callus now called bony callus ; stage last 3-4 months  Bone remodeling = the spongy bone of callus is replaced by compact bone in the periphery Effect of age and immobility on bone; effect to exercise on bone Age & Bone: 1) Results in less of minerals (demineralization) & brittleness (low protein synthesis) 2) Demineralization begins >30 in females, accelerating after 45 with loss of estrogen; 30% bone Ca+ is lost by 70 years (8%/10 years) In males Ca+ loss begins >60 with 3% lost /10 yrs 3) Loss of protein synthesis occurs in elderly 4) osteoporesis is the loss of bone mass where the bone becomes increasingly brittle and subject to fractures; the basic problem is that bone resorption outpaces bone deposition in large part due to the depletion of Ca+ from the body – lsot to feces, urine and sweat  it mostly affects spongy bone  it affects postmenopausal women  vertebrae lose spongy bone & they become compressed giving the person a deformed spine (widow’s hump) and loss of stature  men over 70 will develop this also (losing 30% of bone mass) while women will have lost 50% of their bone mass  in women, estrogen stimulate OB & the ovaries stop producing this hormone after menopause. Estrogen replacement (ERT) or hormone replacement therapy (HRT- both E & P) can slow down this process, not prevent it, but they carry hazards of BC. Even athletes can develop this, especially if they become anemic  The drug Raloxifene mimics the beneficial effects of “E” on bone without the risk of BC, and a new drug (Fosamax) is nonhormonal, and blocks resorption of bone by OC  prevention is the greatest cure. Between the ages of 25-40, the more bone mass developed, the less effect this condition will have on the person 5) Osteomalacia = is a disorder in which bones fail to calcify although the collagen is produced, mineral salts aren’t deposited and bones are “rubbery” or soft and easily deformed. This is sometimes called “adult rickets” so that new bone fails to calcify. The disorder varies in degrees of pain or tenderness and bone fractures are common.

MUSCLE: Chapter 10  Types and functions & characteristic of muscle tissue (excitability etc) 1. electrical excitability = property of all living things, but muscle can respond to stimuli in unique way, they produce electrical current along the PM that triggers contraction of the cell 2. contractility = they shorten in a unique way; there are 2 modes of contraction 3. extensibility = in order to contract, they must be able to extend or stretch without damage. Extensibility allows a muscle to contract forcefully even if it is stretched. During normal activities, the stretch on skeletal muscle remains constant 4. elasticity = the ability of muscle to return to its original shape and length after contraction or extension 

Different connective tissue coverings (perimysium covers the fascicle 1. fascia - is the CT component surrounding muscles, organs / it is fibrous CT; there is superficial and deep fascia 2. deep fascia - is the dense, irregular CT that is deep and intimately surround the muscle  outermost layer of deep fascia around muscle is the epimysium  sends layers into the muscle bundles and fibers that surround 10-100 muscle fibers (fascicles) and this is the perimysium ( also dens, irr. CT); many fascicles are large enough to be seen with the naked eye- they give the cut of meat it characteristic “grain” and if you tear the meat, you tear it along the fascicles.  penetrating into the fascicles surrounding each fiber is the endomysium (LCT)  The peri- epi & endomysium all are continuous with the CT that attaches muscle to bone & other structures. All these layers extend beyond the muscle fibers to form a tendon – cord of dense, regular CT that attaches muscle to the periosteum of bone. (EX: calcaneal (Achilles) tendon of the gastrocnemius muscle  When the CT expend as broad, flat layers, it is called an aponeurosis

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Anatomy of a muscle fiber; anatomy of the NMJ; neurotransmitter at NMJ A. muscle fiber:  the plasma membrane of a muscle fiber is the sarcolemma  the cytoplasm of a muscle fiber is the sarcoplasm, which has a considerable amount of glycogen. In addition, there is a lot of red-colored myoglobin only found here. It is a protein that binds oxygen, and releases it to mitochondria as needed . Myoglobin diffuses in from the ICF.  the muscle fibers arise from the fusion of many myoblast and is m...