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143 Cards in this Set
- Front
- Back
Tissues:
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collections of cells/cell products performing specific, unified functions (histology)
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Epithelial:
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cover exposed surfaces; line internal passageways; form glands
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Connective:
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protect/support body, organs; bind organs together; store energy; immunity
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Muscular:
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generates physical force
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Nervous:
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detect changes inside & outside body; initiate & transmit nerve impulses
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Epithelium can be 2 types:
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1. Covering & lining: skin; organ coverings; line cavities, CV/resp/GI/urinary/repro systems; ducts
2. Glandular: secreting portion |
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Epithelial Tissue: Functions
1. 2. 3. |
Protection
Secretion/absorption Permeability |
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General Epithelial Features:PACAR
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1) Polarity: apical, basal surfaces
2) Attachment: to basement membrane 3) Cellularity: tightly packed, cell junctions 4) Avascularity 5) Regeneration: cell division |
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Covering & Lining Epithelium is Classified by arrangement of ___.
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cell layers
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Covering & Lining Epithelium
Simple must be: Pseudo-stratified helps: Stratified Must be: |
1. MUST BE PERMEABLE diffusion, osmosis, filtration, secretion, absorption
2.HELPS STUFF MOVE often ciliated, mucus 3. MUST BE TOUGH protects underlying tissue from wear & tear |
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Covering & Lining Epithelium
Also classified by cell shape 1. 2. 3. |
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Covering & Lining Epithelium
Squamous must be: |
MUST BE PERMEABLE
thin, allows substances to pass through them |
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Covering & Lining Epithelium
Cuboidal cells act as the ___: ___,___ |
EXCHANGE CENTER secretion, absorption
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Covering & Lining Epithelium
columnar cells as the 2nd ___: also ___. ___ |
EXCHANGE CENTER 2 secretion, absorption
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Epithelial Cells Connections: Cell Adhesion Molecules
Tight Junctions: 1. Prevent passage of ___, solutes. 2. Isolates substance in lumen |
Prevent passage of H2O, solutes
Isolates substance in lumen |
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Epithelial Cells Connections: Cell Adhesion Molecules
Gap Junctions 1. Allows ___to pass 2. Coordinate ___contractions |
Gap Junctions
Allows ions to pass Coordinate heart contractions |
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Epithelial Cells Connections: Cell Adhesion Molecules
Desmosomes 1. ___cells together 2. Allow ___&___ |
Desmosomes
Ties cells together Allow bending & twisting |
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Epithelial Cells Connections: Cell Adhesion Molecules
Hemidesmosomes 1. Attach to ___membrane |
Hemidesmosomes
Attach to basement membrane |
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Simple Squamous Epithelium
Locations: Functions: |
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Simple Cuboidal Epithelium
Locations: Functions: |
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Simple Columnar Epithelium
Location: Function: |
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Pseudostratified Columnar Epithelium
Locations: Functions: |
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Stratified Squamous Epithelium
Locations: Functions: |
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Stratified Cuboidal Epithelium
Locations: Functions: |
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Stratified Columnar Epithelium
Locations: Functions: |
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Transitional Epithelium
Locations: Functions |
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Glandular Epithelium
2 types of glands: 1. ___: substances enter extracellular fluid and into bloodstream without flowing thru ducts -Pituitary, thyroid, adrenal 2. ___: substances enter ducts that empty at surface of covering or lining epithelium -Sweat, salivary, mammary |
1. Endocrine: substances enter extracellular fluid and into bloodstream without flowing thru ducts
-Pituitary, thyroid, adrenal 2. Exocrine: substances enter ducts that empty at surface of covering or lining epithelium -Sweat, salivary, mammary |
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Exocrine Glandular Features
Structure 1. Unicellular: 2. Multicellular: |
Structure
1. Unicellular: individual secretory cells 2. Multicellular: organs w/ glandular epithelium |
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Exocrine Glandular Features
Secretions 1. Serous: watery, contains ___. -Parotid salivary glands 2. ___: mucins + water = mucus --Sublingual salivary glands 3. ___: 1+ types of gland cells, 2 secretions --Submandibular salivary glands |
Secretions
Serous: watery, contains enzymes Parotid salivary glands Mucous: mucins + water = mucus Sublingual salivary glands Mixed: 1+ types of gland cells, 2 secretions Submandibular salivary glands |
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Exocrine Modes of Secretion:
1. Merocrine 2. Apocrine 3. Holocrine |
1. Merocrine
2. Apocrine 3. Holocrine |
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Exocrine Modes of Secretion
Merocrine: |
Release via exocytosis
Most common |
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Exocrine Modes of Secretion:
Apocrine: |
Loss of both product and cytoplasm
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Exocrine Modes of Secretion
Holocrine: |
Cell fills with product, bursts to release
Gland cells replaced by stem cells |
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Structural Classes of Exocrine Glands
SIMPLE GLANDS vs COMPOUND GLANDS |
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Connective Tissue Functions
Structural framework Transport ___, dissolved ___ Protect delicate ___ Supporting/surrounding/interconnecting Energy ___ Defend from ___ |
Structural framework
Transport fluids, dissolved materials Protect delicate organs Supporting/surrounding/interconnecting Energy reserves Defend from microorganisms |
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Connective Tissue
Most ___tissue type! Found btwn other ___, hence the name |
Most common tissue type!
Found btwn other tissues, hence the name |
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Connective Tissue
Consists of small cells far apart in lots of ___material (___) |
Consists of small cells far apart in lots of extracellular material (matrix)
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Connective Tissue
Matrix = ___fibers + ___substance --Secreted by cells, determines tissue ___. --Matrices from cells as diverse as cells themselves |
Matrix = protein fibers + ground substance
Secreted by cells, determines tissue qualities Matrices from cells as diverse as cells themselves |
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Connective Tissue
Good ___supply (well vascularized) Exception: cartilage is avascular |
Good blood supply (well vascularized)
Exception: cartilage is avascular |
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Connective Tissue Elements:
1. 2. 3. |
Cells, Matrix protein fibers, Matrix ground substance
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Connective Tissue Elements:
Cells Provide: |
structure, immune function, energy storage
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Connective Tissue Elements:
Matrix protein fibers 1. Produced by ___ ___ cells 2. C___, e___, r___ 3. Give structure, flexibility, elasticity, strength |
Matrix protein fibers
1. Produced by connective tissue cells 2. Collagen, elastic, reticular 3. Give structure, flexibility, elasticity, strength |
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Connective Tissue Elements:
Matrix ground substance 1. Secreted by ___ ___ cells 2. Can be ___, ___, ___(H2O + organic molecules) 3. Affects how tissues develop, migrate, proliferate, change shape, function, etc. |
Matrix ground substance
1. Secreted by connective tissue cells 2. Can be liquid, gel, solid (H2O + organic molecules) 3. Affects how tissues develop, migrate, proliferate, change shape, function, etc. |
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Connective Tissue Classes:
1. 2. 3. |
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Connective Tissue Elements:Protein Fiber Types
1. 2. 3. |
1. Collagen fibers
2. Reticular fibers 3. Elastic fibers |
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Connective Tissue Elements:Protein Fiber Types
Collagen fibers (e.g., tendons, ligaments) 1. Most ___connective fiber 2. Long, straight, ___, ___ 3. Resists force in ___ direction |
Collagen fibers (e.g., tendons, ligaments)
1. Most common connective fiber 2. Long, straight, STRONG, FLEXIBLE 3. Resists force in 1 direction |
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Connective Tissue Elements:Protein Fiber Types Reticular fibers (e.g., sheaths around organs)
1. Network of interwoven fibers (___) 2. Strong, flexible, resists force in ___directions 3. Stabilizes ___cells (___), structures |
Reticular fibers (e.g., sheaths around organs)
1. Network of interwoven fibers (stroma) 2. Strong, flexible, resists force in many directions 3. Stabilizes functional cells (parenchyma), structures |
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Connective Tissue Elements:Protein Fiber Types Elastic fibers (e.g., aorta)
1. ___& ___to original position; wavy |
Elastic fibers (e.g., aorta)
1. Stretch & return to original position; wavy |
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Mesenchymal:
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stem cells for all connective tissues
CTP |
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Fibroblasts:
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most abundant, secrete hyaluronan & proteins to make GS viscous
CTP |
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Melanocytes:
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melanin-releasing cells in skin CTP
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Adipocytes:
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fat cells CTP
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Macro/microphages:
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scavenge pathogens, damaged cells, respond to injury/infection CTP
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Mast:
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release histamine, heparin--> inflammation CTP
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Lymphocytes:
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defend body, respond to damage CTP
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Connective Tissue Proper:Loose (“packing peanuts”)
1. 2. 3. |
1. Areolar
2. Adipose 3. Reticular |
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Connective Tissue Proper:
Areolar 1. Many cell ___, all ___, open ___ 2. Near ___, part of ___tissue |
Areolar
1. Many cell types, all fibers, open framework 2. Near epithelia, part of subcutaneous tissue |
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Connective Tissue Proper:
Adipose 1. Adipocytes, which hold ___ droplets 2. Found w/ ___tissue; energy, protects ___ |
Adipose
1. Adipocytes, which hold TG droplets 2. Found w/ areolar tissue; energy, protects organs |
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Connective Tissue Proper:
Reticular 1. ___fibers & cells 2. Forms ___ for lymph organs (spleen, lymph nodes, marrow), liver, kidneys; filtration |
1. Reticular fibers & cells
2. Forms mesh scaffold for lymph organs (spleen, lymph nodes, marrow), liver, kidneys; filtration |
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Connective Tissue Proper:___ ___
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Connective Tissue Proper:Loose Adipose
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Connective Tissue Proper:___ ___
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Connective Tissue Proper:Loose Reticular
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CTP Dense-Types:
1. 2. 3. 4. |
Regular
Irregular Elastic Dense regular |
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CTP Dense-Types:
Regular 1. Contains ___ collagen pattern, fibroblasts 2. Ligaments, tendons |
Regular
Contains parallel collagen pattern, fibroblasts Ligaments, tendons |
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CTP Dense-Types:
Irregular 1. Contains ___collagen pattern, fibroblasts 3. ___, ___valves, membranes, ___ |
1. Contains irregular collagen pattern, fibroblasts
3. Dermis, heart valves, membranes, joints |
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CTP Dense-Types:
Elastic 1. Dense ___+ elastic fibers, fibroblasts 2. ___tissue, ___walls, vertebral ligaments |
Elastic
1. Dense regular + elastic fibers, fibroblasts 2. Lung tissue, artery walls, vertebral ligaments |
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Connective Tissue Proper:Dense Regular
Locations: Functions |
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Connective Tissue Proper:Dense Irregular-
Locations: Functions: |
INTERWOVEN NETWORKS OF COLLAGEN FIBERS
Layered in skin, perichondrium, periosteum, some organ capsules |
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Connective Tissue Proper:Dense Elastic
Locations: Functions: |
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Connective Tissue Proper:Fasciae
Connective Tissue Framework 1. 2. 3. |
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Fluid Connective Tissues
Types 1 2 |
Blood
Lymph |
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Fluid Connective Tissues
1. Blood --Cells: ___,___,___ --Fluid matrix: ___(proteins are dissolved) |
1. Blood
--Cells: RBCs, WBCs, platelets --Fluid matrix: plasma (proteins are dissolved) |
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Fluid Connective Tissues
Lymph 1. Cells: some ___ --Fluid matrix: ___(proteins are dissolved) --Plasma -> ___fluid -> lymph |
Lymph
1. Cells: some WBCs --Fluid matrix: lymph (proteins are dissolved) --Plasma -> interstitial fluid -> lymph |
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Fluid Connective Tissues
Blood and Lymph |
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Supporting Connective Tissues
1. Less ___cell population 2. Dense ___ ___ Closely packed ___ |
Less diverse cell population
Dense ground substance Closely packed fibers |
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Supporting Connective Tissues
2 types: |
Cartilage
Bone |
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Supporting Connective Tissues Cartilage-
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Gel-type ground substance
Shock absorption, protection |
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Supporting Connective Tissues
Bone- |
Calcified ground substance (rigid w/ mineral salts)
Support, protection, mineral storage, R(W)BC formation |
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SCT-Cartilage
1. Connective tissue structure --Cells: ___ --Matrix protein fibers: ___(and/or ___) --Matrix GS: proteoglycans from ___sulfate |
1. Connective tissue structure
--Cells: chondrocytes --Matrix protein fibers: collagen (and/or elastic) --Matrix GS: proteoglycans from chondroitin sulfate |
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SCT-Cartilage
1. Avascular --___secrete ___factors |
1. Avascular
--Chondrocytes secrete antiangiogenic factors |
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SCT-Cartilage
1. ___ --Membrane layer of dense irregular tissue --Outer fibrous layer: ___producing collagen --Inner ___layer: becomes –blasts, -cytes |
1. Perichondrium
--Membrane layer of dense irregular tissue --Outer fibrous layer: fibroblasts producing collagen --Inner chondrogenic layer: becomes –blasts, -cytes |
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Supporting Connective Tissue: Cartilage—Perichondrium
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Supporting Connective Tissue: Cartilage—Perichondrium
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Supporting Connective Tissue: Cartilage—Types
1. 2. 3. |
1.Hyalin
2.Elastic 3.Fibrocartilage |
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Supporting Connective Tissue: Cartilage—Types
Hyaline: |
flexible, shock absorber, weakest
--Translucent matrix, fine (invisible) collagen fibers --Ends of bones, nose, fetal skeleton |
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Supporting Connective Tissue: Cartilage—Types
Elastic: |
maintain shape
--Tightly packed elastin threads (hairy appearance) --External ear, eustachian tubes, epiglottis |
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Supporting Connective Tissue: Cartilage—Types Fibrocartilage:
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rigid, strong
Very densely bundled collagen fibers --Sparse cell distribution --Knees, between vertebrae |
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Supporting Connective Tissue:Hyaline Cartilage
Location: Function: |
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Supporting Connective Tissue:Elastic Cartilage
Location: Function: |
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Supporting Connective Tissue:Fibrocartilage
Location: Function: |
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STC: Cartilage—Growth
Interstitial growth |
Chondrocytes in matrix divide, produce additional matrix
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SCT: Cartilage—Growth
Appositional growth |
Perichondrium divides, cartilage grows by adding to outer layer
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SCT:Bone (Osseus Tissue)
Cell types: 1. Osteocytes- 2. Osteoblasts- 3. Osteoclasts- |
1. Osteocytes maintain mineral content
2. Osteoblasts produce fibers/matrix 3. Osteoclasts dissolve fibers/matrix |
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SCT:Bone (Osseus Tissue)
Mineralized matrix Organic: ___ Inorganic ___ |
Mineralized matrix
Organic: 35% Inorganic 65% |
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SCT: Bone (Osseus Tissue)
2 classifications: 1. Compact 2. Cancellous (or “spongy”; not shown) |
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Supporting Connective Tissue:Cartilage vs. Bone
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Muscle Tissue
Three types: |
Three types
Skeletal Cardiac Smooth |
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Skeletal Muscle Tissue
Location: Function: |
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Cardiac Muscle Tissue:
Locations: Functions: |
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Smooth Muscle Tissue
Location: Function: |
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Nervous Tissue
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Body Membranes:
1. 2. 3. 4. |
Body Membranes:
1. Mucus m.: 2. Serous m.: 3. Synovial m.: 4. Cutaneous m.: |
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Mucus m.: |
Mucus m.: connective, epithelial
Line GI, respiratory, urinary, reproductive tracts Moisture reduces friction; promotes absorption |
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Body Membranes:
Serous m.: |
connective, epithelial
Line closed cavities & surround organs Reduce friction, parietal vs. visceral Pleural, pericardium, peritoneum |
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Body Membranes:
Synovial m.: |
connective
Line joint cavities, synovial fluid to reduce friction |
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Body Membranes:
Cutaneous m.: |
connective, epithelial (SKIN!)
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The Integumentary System
___system of the body |
Largest system of the body
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The Integumentary System
"Cutaneous membrane” ___: outer ___: inner |
Cutaneous membrane”
Epidermis: outer Dermis: inner |
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The Integumentary System
Accessory structures ___, ___,___ |
Accessory structures
Hair, nails, glands |
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The Integumentary System
Subcutaneous layer (___) ___tissue, ___tissue |
Subcutaneous layer (hypodermis)
Adipose tissue, areolar tissue |
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The Integumentary System
Functions 1.P 2.E 3.T 4.N 5.V 6.S |
Protective barrier
Excretion Thermoregulation Nutrient storage (adipose) Vitamin D3 synthesis --UV light Sensory detection --Touch, pressure, pain, temp |
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The Integumentary System:Components
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Skin Layers:Epidermis—protective Cell Make up
1. 2. 3. 4. |
Cell Make up
1. Keratinocytes 2. Melanocytes 3. Langerhans cells 4. Merkel cells |
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Skin Layers:Epidermis—
Keratinocytes: |
90% of epidermis
Make keratin (protective, waterproof) |
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Skin Layers:Epidermis— Melanocytes:
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8% of epidermis
Make melanin, transfer to keratinocytes |
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Skin Layers:Epidermis—Langerhans cells
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Immune response
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Skin Layers:Epidermis—
Merkel cells |
Detect touch, pressure
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Skin Layers:Epidermis—
1. Mechanical ___ 2. Prevents ___ 3. Defense against ___ 4. ___(nutrients diffuse in from dermis) |
1. Mechanical protection
2. Prevents fluid loss 3. Defense against microorganisms 4. Avascular (nutrients diffuse in from dermis) |
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Skin Layers:Epidermis—
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Skin Layers:Epidermis—
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Skin Layers:Epidermis—Stratum Basale
1. ___layer |
1. Deepest layer
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Skin Layers:Epidermis—Stratum Basale
Cells: 1. Basal (___) cells 2. Melanocytes 3. Merkel cells (___) Cells divide, push up & interlock (___) |
Cells:
1. Basal (stem) cells 2. Melanocytes 3. Merkel cells (glabrous) Cells divide, push up & interlock (stability) |
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Skin Layers:Epidermis—Stratum Basale
Epidermal ridges (___. ___) |
Skin Layers:Epidermis—Stratum Basale
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Skin Layers:Epidermis—Stratum Basale
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Skin Layers:Epidermis—Stratum Granulosum
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Skin Layers:Epidermis—Stratum Lucidum
1. Not in most skin 2. Areas of constant ___ --___, ___ 3. Translucent layer 4. Cells flattened, packed close together |
Stratum Lucidum
1. Not in most skin 2. Areas of constant Pressure --Soles, palms 3. Translucent layer 4. Cells flattened, packed close together |
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Skin Layers:Epidermis—Stratum Corneum
1. “___” surface 2. ___cells shed 3. Discourages ___ 4. Water ___ --Lose or gain water slowly 300-400 mL/day vs3-4 L/day |
Stratum Corneum
1. “Exposed” surface 2. Dead cells shed 3. Discourages microbes 4. Water resistant --Lose or gain water slowly 300-400 mL/day vs3-4 L/day |
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Skin Layers:Epidermis and Water Movement
1. Hydration (water ___) From immersion in ___soln (osmosis) Causes stretching & ___of skin 2. Dehydration (water ___) Damage to stratum ___(burns, blisters) Immersion in ___soln (osmosis) 3. Insensible perspiration Interstitial fluid ___thru stratum ___ 4. Sensible perspiration Water ___by sweat glands in ___ |
1. Hydration (water gain)
From immersion in hypotonic soln (osmosis) Causes stretching & wrinkling of skin 2. Dehydration (water loss) Damage to stratum corneum (burns, blisters) Immersion in hypertonic soln (osmosis) 3. Insensible perspiration Interstitial fluid evaporated thru stratum corneum 4. Sensible perspiration Water excreted by sweat glands in dermis |
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Skin Layers:Epidermis and Vitamin D
1. 7-___--> ___ Pre-vitamin D3 --> ___vitamin D3 --Conversion requires ___radiation |
1. 7-Dehydrocholesterol --> cholecalciferol
Pre-vitamin D3 --> inactive vitamin D3 --Conversion requires UV radiation |
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Skin Layers:Epidermis and Vitamin D
1. ___, ___convert into calcitriol |
1. Liver, kidneys convert into calcitriol
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Skin Layers:Epidermis and Vitamin D
Insufficient vitamin D3 1. ___(children) 2. ___(adults) |
Insufficient vitamin D3
1. Rickets (children) 2. Osteomalacia (adults) |
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Skin Layers:Epidermis and EGF
1. ___ ___ ___(EGF) --Powerful ___growth factor --Produced by ___& duodenal glands --Used to grow skin ___ |
1. Epidermal Growth Factor (EGF)
--Powerful peptide growth factor --Produced by salivary & duodenal glands --Used to grow skin grafts |
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Skin Layers:Epidermis and EGF
1. Functions: --Promotes division of ___cells --Accelerates ___production --Stimulates ___repair --Stimulates ___secretions |
Skin Layers:Epidermis and EGF
1. Functions: --Promotes division of germinative cells --Accelerates keratin production --Stimulates epidermal repair --Stimulates glandular secretions |
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Skin Layers:Dermis—Circulation
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Skin Layers:Dermis
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Skin Layers:Dermis—Nerves
1. ___nerves --Blood flow --Gland secretions 2. ___nerves --Meissner corpuscles Light touch—”tactile corpuscles” --___corpuscles Deep pressure—”lamellated corpuscles” --___nerve endings Temperature, pain, itch, tickle |
Skin Layers:Dermis—Nerves
1. Autonomic nerves --Blood flow --Gland secretions 2. Sensory nerves --Meissner corpuscles Light touch—”tactile corpuscles” --Pacinian corpuscles Deep pressure—”lamellated corpuscles” --Free nerve endings Temperature, pain, itch, tickle |
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Skin Layers:
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Skin Layers:
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Skin Layers: Hypodermis“___”
1. Continuation of loose CT below ___ 2. Adipose, areolar ___ skin against underlying organs |
Hypodermis“Subcutaneous”
1. Continuation of loose CT below dermis 2. Adipose, areolar Stabilized skin against underlying organs |
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Skin Accessory Structures: Hair
1. ___ 2. Everywhere except ___ skin --Palms, soles, lips 3. Dead, ___epidermal cells --Shaft, root, bulb Arrector pili, oil glands |
1. Protective
2. Everywhere except glabrous skin --Palms, soles, lips 3. Dead, keratinized epidermal cells --Shaft, root, bulb Arrector pili, oil glands |
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Skin Accessory Structures: Hair
1. Vellus (peach fuzz) 2. Terminal hairs (heavy) 3. Club hair --Cessation of growth --Hair growth cycle 4. Color, texture a. Genetic b. Environmental c. Hormonal |
1. Vellus (peach fuzz)
2. Terminal hairs (heavy) 3. Club hair --Cessation of growth --Hair growth cycle 4. Color, texture a. Genetic b. Environmental c. Hormonal |
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Skin Accessory Structures:
1. Hair Internal & external root sheaths 2. Cuticle, cortex, medulla of hair 3. Base of follicle: ___ --___ active source of cells |
1. Hair Internal & external root sheaths
2. Cuticle, cortex, medulla of hair 3. Base of follicle: bulb --Mitotically active source of cells |
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Skin Accessory Structures: Glands Sebaceous
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Skin Accessory Structures: Glands Apocrine and Merocrine
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Skin Accessory Structures: Nails
1. Plates of hard-packed dead ___cells 2. Nail body:___ 3. Free edge: ___ 4. Root: ___ |
1. Plates of hard-packed dead keratinized cells
2. Nail body: visible portion 3. Free edge: what you trim 4. Root: form new nail cells deep to this |
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Injury & Repair
Regenerates easily: 1) ___, 2) ___, 3) ___ |
Regenerates easily: 1) Scab, 2) Granulation, 3) Scar
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Injury & Repair
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Injury & Repair
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Skin Functions: Thermoregulation
1. ___ --Evaporative cooling in the heat --Works better in ___ climates 2. Vasodilation --As body temp ___, skin blood vessels ___, allow more blood to give off heat 3. Vasoconstriction --As body temp ___, skin blood vessels ___, allow less blood to give off heat |
1. Sweat
--Evaporative cooling in the heat --Works better in dry climates 2. Vasodilation --As body temp rises, skin blood vessels dilate, allow more blood to give off heat 3. Vasoconstriction --As body temp falls, skin blood vessels constrict, allow less blood to give off heat |