Histology I. Introduction A. Definitions B. Types

1. EpitheliumCovering / Lining and forms most Glands

2. ConnectiveFibrous with extracellular matrix

3. MuscularFibrous with intracellular matrix

4. NervousPacked with cellular matrix

II. Epithelial Tissue A. Defining Characteristics

1. Densely packed cells with a “free” surface 2. Avascular 3. “Bound” surface underlain with Connective Tissue and basement membrane “bm” 4. Not innervated

B. Functions

1. Protection from entry or exit 2. Excretory & Secretory 3. Absorptive 4. Sensory Reception 5. Separates two environments

C. Classification of Epithelial Sheets

2. Based on cellular shape a. Simplec. Stratifiedb. Pseudostratified 1. Based on number of cell layers a. Squamousb. Cuboidalc. Columnar

a. Simple Squamous 3. Classes & Functions Figure 4.3a

3. Classes & Functions b. Simple Cuboidal Figure 4.3b

3. Classes & Functions c. Simple Columnar Figure 4.3c

d. Pseudostratified Figure 4.3d

e. Stratified Squamousf. Stratified Cuboidal & Columnar Figure 4.3e

g. Transitional Figure 4.3f

D. Classification of Epithelial Glands

2. Based on Complexity a. Exocrineb. Endocrine 1. Based on Function a. Unicellularb. Multi-cellular 3. Based on Mode of Secretion c. Holocrineb. Apocrinea. Merocrine

Figure 4.4

Figure 4.5

Figure 4.6

III. Connective Tissue A. Defining Characteristics

1. Cells embedded into matrix (ground substance and fibers) 2. Vascular supply 3. Many cell types but one resident cell 4. Innervated 5. Function depends on location and packing of fibers

B. Cell Types

1. Fibroblast 2. Macrophage 3. Plasma Cell 4. Mast cell 5. Adipocyte

Figure 4.7

C. Fiber Types

1. Collagen 2. Elastin 3. Reticular

D. Classes

2. Based on Density of Ground Substance a. Looseb. Dense 1. Based on Packing of Fibers (Proper) a. Cartilageb. Bonec. Blood

Figure 4.8a 1a. Proper Loose C. T., Areolar

1a. Proper Loose C. T., Adipose Figure 4.8b

1a. Proper Loose C. T., Reticular Figure 4.8c

1b. Proper Dense C. T., Regular Figure 4.8d

1b. Proper Dense C. T., Irregular Figure 4.8e

1b. Proper Dense C. T., Elastic Figure 4.8f

2a. Cartilage C. T., Hyaline Figure 4.8g

2a. Cartilage C. T., Elastic Figure 4.8h

2a. Cartilage C. T., Fibrocartilage Figure 4.8i

2b. Bone C. T., Compact vs. Cancellous (or spongy) Figure 4.8j

2c. Blood C. T. Figure 4.8k

IV. Nervous Tissue A. Defining Characteristics

1. Packed cells mostly designed for rapid communication 2. Classed based on location and direction of impulses 3. Highly vascularized with barriers

1. Packed cells Figure 4.9

2. Location and Direction

V. Muscle Tissue A. Defining Characteristics

1. Packed cells (called fibers) filled with contractile proteins 2. Classed based on organization of proteins 3. Highly vascularized 4. Highly Innervated

B. Classes

1. Based on Location and Organization of Fibers a. Skeletal Figure 4.10a

1. Based on Location and Organization of Fibers b. Cardiac Figure 4.10b

1. Based on Location and Organization of Fibers c. Smooth Figure 4.10c

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