Anatomy Exam 1 Review PDF

Exam 1 Review Cells ​ Glycoproteins: carbohydrates attached to protein on plasma membrane surface ​ Glycolipids: lipids attached to proteins on plasma membrane surface ​ Glycoproteins and glycolipids form glycocalyx (cell coat) ​ Lipid raft: high concentration of cholesterol...

Exam 1 Review Cells ​ Glycoproteins: carbohydrates attached to protein on plasma membrane surface ​ Glycolipids: lipids attached to proteins on plasma membrane surface ​ Glycoproteins and glycolipids form glycocalyx (cell coat) ​ Lipid raft: high concentration of cholesterol molecules ​ Mitochondria: in all cells except RBCs and terminal keratinocytes ​ ER: ERAD-> ER associated protein degradation, targets and kicks out poorly folded protein, degraded by proteasomes ​ Golgi apparatus: modifies and completes protein synthesis begun by ER, sh​ ipping vacuoles ​ Microtubules: guide vesicle movement, form near nucleus + grow out ○​ Actin filaments, in all cells with nucleus, form microvilli, extension of cell processes, movement of cell, anchorage and movement of membrane proteins ○​ Mitosis ​ Intermediate filaments: support + structure, “ropes” ○​ Keratin: epithelial cells ○​ Vimentin: mesoderm-derived cells (muscle, glial) ○​ Neurofilaments: neurons ○​ Lamins: in nucleus of cells ​ Nucleus ○​ Nuclear envelope: bilayer with perinuclear space between them and nuclear pores which regulate transport ○​ Chromatin: c’somal material ○​ Nucleolus: active site of rRNA synthesis ○​ Nucleoplasm: material w/in nucleus that is not chromatin or nucleolus ​ Stem cells: when do first division, one cell remains stem cell and other cell differentiates Epithelial ​ Avascular ​ Has nerve supply ​ High capacity for renewal ​ Two types: covering (skin, gut, ect) and glandular (all glands develop from epithelia) ​ Lamina propria: connective tissue that epithelia lining cavity of internal organs rests on ○​ Papillae: evaginations in the connective tissue ​ Basal lamina: binds epithelium to underlying connective tissue ○​ Type IV collagen, glycoproteins, proteoglycans ○​ Need electron microscope to view ​ Basement membrane: formed by basal lamina and reticular lamina ○​ Seen with light microscope + specific stain ​ Intercellular junctions ○​ Tight junctions (zonulae occludens): most apical junction ​ Involves transmembrane protein occludin and claudin ○​ Zonula adherens (adherens junctions): anchors cells together, connects cytoskeleton (actin filaments) of one cell to another ○​ Desmosome (macula adherens): intermediate filaments, not whole length of cells ○​ Hemidesmosome: join epithelial cells to basal lamina ​ Involve integrins (transmembrane proteins) ​ Intermediate filaments ○​ Cadherins: anchors cells together in zonula adherens, role in suppressing epithelial tumor cells ○​ Integrins: interact with basal lamina (laminin and type IV collagen) and ECM of connective tissue ​ Affect cell shape and movement ○​ Gap junctions: cell communication, form small diffusion channel between adjacent cells (important in nerve and cardiac cells), cell signaling ​ Formed by connexin ​ Terminal web: region at base of microvilli made of web of microfilaments ​ Anything that enters or leaves the body must pass through epithelium ​ Free surface specialization ○​ Cilia: move mucus and other substances ​ Mainly in trachea, bronchi, oviduct ○​ Microvilli: increase surface area ​ Brush border of kidney tubule cell ​ Striated border of intestinal absorptive cell ○​ Stereocilia (long microvilli): only in epididymis and sensory (hair) cells of inner ear  ​ Covering epithelia ○​ Simple squamous epithelium ​ Endothelium: internal lining of heart and blood vessels ​ Mesothelium: internal lining of ventral body cavities ○​ Simple cuboidal: secretion (sweat or tears), absorption ○​ Simple columnar: protective, secretion, absorption ​ Ciliated: moves mucous and other substances ​ Non-ciliated: goblet cells (secrete mucous) and absorptive cells (have microvilli) ○​ Stratified squamous epithelium: superficial layers flat, deeper layers more cuboidal, deepest have continuous cell division ​ Keratinized: cornified, dry, tough, water resistant ​ Non-keratinized: non-cornified, wet, oral cavity ○​ Pseudostratified columnar: appears to be multiple layers but is not, all cells attached to basement membrane, some cells do not reach free surface ​ Secrete or may be ciliated ​ Seen mostly in respiratory system ○​ Transitional epithelium: special stratified epithelium, lines pelvis of kidney, ureters, bladder, and part of urethra ​ Cells change shape according to degree of distention of the organ ​ Glandular epithelia ○​ Exocrine: secrete into ducts, usually divided into lobes and lobules ​ Types of secretions ​ Serous, mucous, mixed ​ Unicellular: goblet cells is the only important one ​ Found in GI and respiratory systems ​ Scattered cells w/in epithelium ​ Secrete mucins that form mucus (lubricant) ​ Multicellular: secretory sheet (ex: lining of stomach) ​ Tubular invagination ​ Duct: simple and compound (branching) ​ Secretory part of gland ○​ Tubular: shaped like tube ○​ Acinar or alveolar: shaped like a blind sac ○​ Endocrine: ductless, secrete into extracellular fluids, diffuse into blood Connective Tissue ​ Facts ○​ Connects tissues together ○​ No free surface (surrounded by epithelium) ○​ Has nerve supply (except for cartilage) ○​ Highly vascular (except cartilage) ○​ Organize tissues ​ Functions ○​ Supports, surrounds, and connects tissues ○​ Forms structural framework of body ○​ Defends from invasion ○​ Protects delicate organs ○​ Transport ​ All connective tissue develops from mesenchyme ​ ECM ○​ Protein fibers ​ Collagen ​ Elastic ​ Reticular ○​ Ground substance: filler ​ Types of cells ○​ Fixed: resident cells, stable, long-lived ​ fibroblasts/fibrocytes ​ One of the most visible resident cells ​ Make collagen and elastin and ground substance (basically ECM) ​ Target of growth factors ​ Usually have long, thin cytoplasmic processes  ​ Nucleus is ovoid and flat ​ Enlarged nucleolus = active ​ Myofibroblasts ​ Have contractile abilities ​ Have properties of fibroblasts and smooth muscle cells ​ Large bundles of myofilaments ​ Contract adjacent to wounds to pull edges together ​ Macrophages (histiocytes) ​ Derived from monocytes ​ Round when in bloodstream, weird shape when enter connective tissue ​ Wandering has ovoid shape in bloodstream ​ Fixed has irregular shape in connective tissue ​ May fuse with other macrophages to form giant one ​ Antigen-presenting cells ​ Mast cells ​ Aid in inflammation, allergic rxns ○​ Heparin, histamine, leukotrienes ​ Large, oval with small nucleus ​ Have granules in cytoplasm ​ Arise in bone marrow ​ Dependent on IgE produced by plasma cells ​ Near small blood vessels ​ NOT in brain or spinal cord ​ Adipose cells ○​ Transient: free/wandering, leave bloodstream and enter connective tissue when called to action, originate mainly in bone marrow, short-lived ​ Leukocytes (WBCs): circulate in bloodstream ​ Lymphocytes ​ Neutrophils ​ Eosinophils ​ Basophils ​ Monocytes ​ Plasma cells: antibody-producing cells derived from B lymphocytes ​ 10-30 dyas lifespan (short) ​ large , oval ​ Golgi ghosts (prominent) ​ Clock face nucleus ​ Found in lamina propria of gastrointestinal tract, respiratory tract, salivary glands ​ Diapedesis: ability of WBCs to leave the bloodstream and enter connective tissue ​ Chemotaxis: chemical trail where the cells need to go ​ Inflammation signs ○​ Pain, redness, swelling, heat, loss of function ​ Terminology ○​ -blast: produces ○​ -cyte: maintains ○​ -clast: breaks down ​ Fibers ○​ Collagen: flexible, high tensile strength ​ Manytypes, type I most common ○​ Reticular fibers: type III collagen ​ Extremely thin, arranged in network or mesh ​ Need special silver stain to see ​ Very delicate and fine, made by fibroblasts ​ Lymph node lymphocytes, delicate blood vessels, smooth muscle fibers ○​ Elastic fibers: thin and straight fibers, arranged in network ​ Can be damaged by UV light/sun -> wrinkles, smoking ​ Ground substance: surround cells and fibers of CT ○​ Amorphous, unstructured ○​ Made of ​ GAGs (glycosaminoglycans): smallest  ​ Single chain of disaccharide molecules ​ Cartilage: chondroitin sulfate ​ Epithelial: keratan sulfate ​ Biggest: hyakuronan ​ PG (proteoglycans): medium ​ Bind collagen together ​ Aggrecan: in cartilage ​ Syndecan: in epithelial cells ​ GP (multiadhesive glycoproteins): largest ​ Fibronectin ​ Interstitium: body-wide network of interconnected, fluid-filled compartments supported by a meshwork of strong, flexible proteins ○​ Part of ECM ○​ Skin, lungs, kidneys, testis, GI tract ​ Connective tissue proper ○​ Loose (areolar): delicate, flexible, very vascular, not resistant to stress ​ Fibroblasts and macrophages most numerous ​ Right next to epithelium ○​ Dense: ​ Irregular: primarily fibroblasts ​ No definite orientation ​ Dermis ​ Sheathes and capsules around joints ​ Regular: primarily fibroblasts ​ Definite orientation ​ Tendon/aponeurosis ​ Ligaments ​ Elastic tissues ​ Embryonic connective tissue ○​ Mesenchyme: mesoderm, gives rise to almost all CT ○​ Mucous connective tissue: primary in umbilical cord, wharton’s jelly, pulp of young teeth ​ Reticular tissue: forms delicate stroma of the lymphoid organs and soft organs ○​ In hematopoietic portion of bone marrow ○​ Around blood vessels ○​ Binds smooth muscles together Adipose tissue ​ Is a type of connective tissue ​ Adipocytes ○​ White: unilocular (one big fat drop), stores energy ​ Make and stores triglycerides ​ Nucleus and cytoplasm displaced against cell membrane ○​ Brown: multilocular (many droplets of fat), heat production ​ Central nuclei, lots of mitochondria ​ Lots in newborns (to stay warm), around core organs in adults ​ Make and store triglycerides ​ Functions as an endocrine organ ○​ Secretes leptin: hormone that binds to cells in brain to signal being full ​ Where come from? ○​ Chylomicrons: circulating fats from intestines, fats that digestive system picks up and puts in bloodstream ○​ VLDLs: very low density lipoproteins, from liver ○​ Synthesized in cell: from glucose, made in adipocyte ​ How mobilized? ○​ Autonomic nervous system and hormones (flight or fight) ○​ Lipase: breaks down triglycerides ​ Regulation ○​ Short term (daily): controls appetite and metabolism ​ Ghrelin: appetite stimulant, eat more food, made in stomach ​ Peptide YY: appetite suppressant, made in large intestine ○​ Long term ​ Leptin: no need more food, have enough fat stored  ​ Insulin: make cells more readily absorb glucose Cartilage ​ Developmental gradient from proximal regions to distal regions ​ Syndactyly: when bones do not form normally ​ Apert’s syndrome: adjacent bones being fused ​ Chondroblasts: start to produce ECM ○​ Chondrocytes: when chondroblast completely surrounded by matrix ​ Reside in lacunae ​ Avascular, no nerves, no lymphatic vessels ​ Support and scaffold for bone formation ​ Surrounded by sheath of dense CT, perichondrium ​ Chondrogenesis: differentiation of mesenchyme into chondroblasts ○​ Interstitial and appositional growth ​ Perichondrium: growth and repair of collagen ○​ Inner cellular layer: chondrogenic layer, source of cartilage cells ○​ Outer layer: has fibroblasts which make collagenous fibers and blood vessels ○​ Found around perimeter of elastic cartilage and hyaline cartilage ○​ NO perichondrium in fibrocartilage and articular cartilage ​ Hyaline cartilage: homogenous amorphous matrix, mostly type II collagen, most common type ○​ Chondrocytes reside in lacunae ○​ Tracheal rings, bronchi, larynx, nose, articular surface (long bones), ends of ribs (costal cartilage) ○​ Mainly type II cartilage ○​ Growth occurs at epiphyseal growth plate (cartilage dies at puberty, max height reached) ○​ Site of interstitial growth ○​ Only found at articular surfaces in adults ○​ Lengthening of long bones ○​ Growth and repair ​ Calcifies before replaced by bone ​ Limited repair bc avascular ​ Aging process includes calcification ​ Elastic cartilage: elastic fibers and elastic lamellae, does not calcify ○​ External ear, external auditory meatus, eustachian tube, epiglottis, parts of larynx ○​ Chondrocytes are large and hypercellular ○​ Surrounded by perichondrium ​ Fibrocartilage: matrix in dense CT, also abundant in type I collagen ○​ Fewer chondrocytes than other cartilage ○​ Shock absorber ○​ Vertebral discs, mandibular condyle, symphysis pubis, sternoclavicular joint, menisci of knee ○​ Mix of dense CT and cartilage Bone ​ Is a type of connective tissue ​ Bone tissue, fat, hematopoietic tissue, blood vessels, nerves, maybe hyaline cartilage ​ Bone matrix (ECM) and three types of bone cells ○​ Bone matrix composed of type I collagen ​ ECM is calcified ​ Functions ○​ Mechanical support ○​ Protection ○​ Mineral homeostasis ○​ Hematopoiesis (all blood cells develop in bone) ​ Compact (cortical bone): dense layer, mainly mechanical and protective function ​ Spongy (trabecular, cancellous): w/trabeculae, mainly metabolic function ○​ Lots of surface area for calcium exchange ​ Cells ○​ Osteoblasts: differentiated bone forming cells, active in protein synthesis ​ Secrete type I collagen and osteoid (initial unmineralized matrix) ​ Promote calcification by alkaline phosphatase secretion ​ Cuboidal in shape, linear arrangement  ​ Become cuboidal when working / secreting osteoid ○​ Osteocyte: osteoblasts that become trapped in bone matrix ​ Occupy lacunae in mineralized matrix ​ Have dendritic processed which travel through bone in canaliculi ​ Long-term viability ​ Can talk to other osteocytes ​ Are always active to maintain the body ○​ Osteoclast: derivatives of monocytes ​ Multinucleated giant cells ​ Resorb bone ​ Enhance calcium release from bone as needed for calcium homeostasis ​ Break down old or damaged bone allowing for new bone formation ​ Reside in Howship lacunae: depressions ​ Have ruffled border when active ​ Periosteum: covers outside of bones, provides essential cellular and biological components necessary for healing and bone repair ○​ Outer layer: dense fibrous CT, vascularized, innervated ○​ Inner layer: source of osteoprogenitor cells, contributes to bone formation ○​ Collagen fibers usually arranged parallel to surface of bone ​ Exception are ligaments and tendon areas (Sharpey’s fibers) ​ Endosteum: surrounds bone marrow on inside, single layer of osteoprogenitor cells, osteoblasts, and small amount of CT ○​ Much thinner than periosteum ○​ Endosteal bone formation ○​ Point of contact with bone marrow ​ Bone vs. cartilage ○​ Cartilage: has chondrocytes in matrix and specialized ECM ​ Mainly type II collagen ○​ Bone: has osteocytes in lacunae in bone and mineralized ECM ​ Osteocytes in direct contact w/one another ​ Mainly type I collagen ○​ Both: have perichondrium/periosteum of two layers ​ Microscopic bone ○​ primary/woven: immature, 1st to appear in development and fracture repair ​ Collagen fibers not organized, less mineralized ○​ secondary/lamellar: mature, replaces primary bone, compact and spongy bone ​ Organized ​ Osteon: concentric lamellae ​ Lacunae connected by canaliculi ​ Perforating canals connect blood vessels in central canals of osteons w/periosteum ​ Bone remodeling ○​ Osteogenesis ​ Endochondral: mesenchyme cells (CT) condense to form cartilaginous “bone” models which will be replaced by ossified tissue ​ Mesenchyme -> cartilage -> bone ​ Intramembranous bone: bone forms directly from condensed mesenchyme cells which differentiate into osteoblasts ​ Most flat bones formed this way (skull) ​ Mesenchyme -> bone