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Tissue: 4 types
1. Epithelial
2. Connective
3. Muscle
4. Neural
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Characteristics
-Cellularity - cells are immediately adjacent from each other / Little or no little extra cellular fluid
-Avascular - no blood cells pass cell
- -Attachment - connected to underlying tissue / generally connected tissue
- *There is a connection point called the basement membrane *Theres the lamina lucida on the epithelial side
- * Theres the lamina densa is the deeper layer (Connected)
- *Together they are called the Basal Lamina
-Polarity - How the organelles are situated in the cytoplasm of the cell located toward the Basal Surface of the cell
- *The exposed surface is called the Apical Surface Epithelial = Coverings & Linings
- -Lumen is the lining inside a tube of a epithelial cell
- Regenerative Has a high Mitotic rate
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Functions
*Protection
*Diffusion
*Absorption
*Just to be slippery
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Specializations
*The ability to secrete (Glands)
*Movement along the epithelial surface
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Simple Epithelial
1 layer of cells
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Stratified Epithelial
2+ more of layers
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Shape of cells
*Squamous (Flattened)
*Cuboidal (Cube Shape)
*Columnar (like columns) Nucleus is much more basal (lower to the cell)
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More on Epithelial Cells...
*Facilitate Absorption
*Simple Squamous - is found in the Alveoli of the lungs
*Capillary beds are only one blood cell thick, on the outside of the alveoli
*Serous Membrance - Find it covering organs. Lining of the Heart, lining of the blood vessels
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2 Types of Strantonized Squamous
Keratinized - Keratin Provides water proofing (SKIN) -
Non Keratinized - Protective but in Moist environments (Oral Cavity, Esophagus, rectum, Anus, Vagina) (Doesn't provided its own water proofing)
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Simple Cuboidal
is found in places with a lot of secretion and absorption *
KIDNEY TUBULES *THYROID FOLLICLES
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Transitional Epithelium-
Transitional - you find this in the Urinary Bladder, Uterus, Uretha
*when the bladder is relaxed it is more cuboidal when full its more flattened
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Simple Coulumnar
*They have microvilli - They can absorb more
*Like the Digestive Tractin the Stomach and Small/Large Intestine
-Goblet Cells -Specialized Glandual Cell - Release digestive enzyme cells in the digestive tract.
***Create Mucus
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Pseudostratified ciliated columnar epithelium
**It appears to be stratified but IT IS NOT
**Cilia they act more like fingers and push things along/Works with Goblet Cells
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Glandular tissue
- Produces Secretions
**Exocrine - secrete products onto the surface
**Endocrine - produce products that go into the blood stream (Hormones)
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***Unicellular --Goblet Cells
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*Multicellular -
*By the types of Secretions
- -Serous - Watery, Enzymes
- -Mucous - secreting a substance called mucin, Add water get Mucus!
- -Mixed =Serous and Mucous
-Method of Secretion
- -Merocrine - most Common released by exocytosis
- -Apocrine - part of cell lost of product
- -Holocrine - The whole cell is lost with release of products
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2. Connective Tissue
*Characteristics
1.Specific compliment of cells
2.Ground Substance *extracellular = Fluid outside of the cell *Watery =Connective Tissue *Semi Fluid =Connective Tissue Proper *Gel-Like =Cartilage *Hard =In Bone
- 3. Fibers (Protein) **Extracellular Matrix is a combo of Fibers & Ground Substances
- A. Collagen - Most common , Long, straight, unbranched/high tensile strength
- B. Elastic - Are thinner, wavy appearnce, and can be branched (stretchy)(150X its normal length)
- C. Reticular - Are very thin and highly branched and interwoven , create a stroma (Net like structure)
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Functions of Connective Tissue
1. Support - Structural Framework
2. Energy Storage
3. Packing and Filling
4. Protective - provides cushioning and shock absorption
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Connective Tissue Proper
Refers to Tissues with extracellular matrix's (Syrupy Ground Substance); relatively few cells
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*CELLS (Connective Tissue Proper)
- 1. Fixed
- a. Fibroblast - Immature form of the cell, can become different types, Most common, Secrete Fibers, Maintenance i. Fixed Macrophage - Stimulate a Immune Response ii.Melanocytes - producing Melanin (pigment) *Sidenote: Albinism - have melanocytes but don't produce pigment iii. Adipocytes - Store extra Lipids
- iv. Mesenchymal - Stem Cells
- b. Wandering - Mature form of the cell
- i. Free Macrophage
- ii. Free microphages
- iii. Lympocytes - White Blood Cells / Can change into Plasma Cells and produce Anti-Bodies
- iv. Mast Cell - histamines (inflammatory response) engulf the dead cells and bacteria coming from the open wound and heparin
- *Inflammatory Response - Injury - Mast Cell release Histamines onto the Capillaries - become leaky - fluid building, Heat,
- Red - Fixed macrophages cause aggregations micro and macro engulf the dead cells
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Loose Connective Tissue
- 1. Areolar, least specialized, all cell types and Fibers are present
- 2. Adipose Tissue - mostly adipocytes
- *Energy Storage
- *Cushioning
- *Space Filler
- *Insulating Tissue
- 3. Reticular Tissue - reticular fibers, fibrablasts, macrophages *Find in the Liver Spleen, Bone Marrow, Lymph-nodes
- A. Loose - few cells ground substances
- B. Dense-Lots of Fibers and few cells
- i.. Dense Regular - Fibers parallel (primarily Collagen) Find in Tendons, Ligaments, Aponeuroses (Sheet Form), Elastic Tissue
- ii.Dense Irregular - Fibers are Multi-directional
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Supporting Connective Tissue
*Cartilage
- 1. Cartilage - (is Avascular) Rubbery Matrix - In the Matrix of types of cells there are Chrondrocyte
- *are in the lacunae*, Protein Fibers ChondroitinSulphates (polysaccharides)
- *Perichondrium - outermost layer is dense irregular and the inner most layer where you have the Mesenchymal (Stem Cells)
- *Appositional - happens in the Perichondrium *Interstitial - Happens in the Chondrocytes
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Supporting Connective Tissue
*3 Types of Cartilage
1.Hyaline - most common, the weakest, least amount of fibers, found in the ribs (Coastal Cartilage) Blue rings in the Resp. Tract
2. Elastic - more elastic fibers than collagen, Auricle of the Ear, Epligottis
3. Fiber - very resistant to compression, Intervert Disc and Pubic synthesis, Knee Joint
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Supporting Connective Tissue
*Bone
2. Bone - Hard Matrix = 1/3 Collagen Fibers and 2/3 Calcium Salts
A. Compact Bone - is found on the outer surface of the bone
- B. Osteocytes - are in Lacunae also
- i. Lamellae - Bone is formed in Concentric Rings inside a (Osteon)
- ii. COnnection points called Canaliculi - movement of material among osteocytes and from vessels in the central Canal (Vessel and Nerve Supply)
- iii. Periosteum has two layers Outer*Dense irregular and the inner is mesenchymal cells
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Supporting Connective Tissue
Fluid Connective Tissue
Fluid Connective Tissue
- 1. Blood -
- a. plasma - the fluid portion is 92% water
- b. Proteins are floating around
- c.The Form Elements : Red Blood Cells/White Blood Cells-Carry out the immune response/Platelets - Help to form blood clots
2. Lymph - Fluid coming from outside of the cell, the Interstitial fluid enters through the lymph vessels / Immune response
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3. Muscule Tissue
- (3 types)
- 1. Skeletal - Primarily attached to bone, Unbranched, long, thin "Muscle Fibers"
- a. Multi Nucleated
- b. Striations - actin and myosin bands
- c. Voluntary
- d. limited ability to repair itself
- 2. Cardiac - Found in the Heart only (Myocardium)
- a. Branched, relatively short, single nucleus, can see Striations
- b. Intercalated discs (gap junctions)
- c. No repair ability
- d. Involuntary - re: control of your heart rate (pacemaker)
- 3. Smooth - is Spindle Shape, Single Nucleus, They are not striated, involuntary, like in the blood vessels, abdominal organs
- a. Can repair itself.
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4. Neural
- a. Neuron
- b. Dendrite - incoming signal
- c. Nucleus
- d. Axon - outgoing signal
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