1. Tissue Types

2. Key Terms Differentiation = produces specialized cells during embryonic development Tissues = groups of cells which are similar in structure and which perform common or related functions Histology = the study of tissues

3. Four Basic Kinds of Tissues Epithelial Tissue Connective Tissue Muscle Tissue Nervous Tissue

4. Epithelial Tissue Locations: – Covers the body – Lines organs, body cavities, and ducts – Forms glands Functions: – Protection from injury and microbial invasion – Regulates permeability – Secretes fluids to lubricate structures

5. Characteristics: Avascular (no blood vessels) Cells may show polarity (apical & basal surface, they are chemically and structurally different from one another) A basement membrane attaches epithelia to underlying connective tissues High rate of cell division (allows repair by sloughing off dead or injured cells, important because epithelium is exposed to physical stress) Epithelial Tissue

6. The Polarity of Epithelial Cells

7. Number of cell layers pg 113 –Simple (single layer) –Stratified (several layers) –Pseudostratified (nuclei are at different levels & not all cells reach the apical surface) Shape of cells (draw, location, function) –Squamous (thin, flat, irregular cells) pg 115 –Cuboidal (cube shaped cells) pg 116 –Columnar, ciliated and nonciliated (tall & slender cells) pg 116, 117 –Transitional (change shape from flat to cuboidal and back) pg 119 Classification of Epithelia

8. Squamous Epithelia

9. Cuboidal Epithelia

10. Cuboidal Epithelia Cont.

11. Special Cuboidal Epithelia: Transitional Epithelia cells can stretch

12. Columnar Epithelia

15. Many epithelia contain gland cells that produce secretions Exocrine glands: –Produce secretions such as mucus and/or watery solution through ducts onto the epithelial surface Endocrine glands: –Ductless, release secretions directly into bloodstream Glandular epithelia

16. Exocrine vs. Endocrine Glands

17. Examples of Exocrine Glands

18. Time to Review Simple squamous epithelium (lining of body cavities) Simple cuboidal epithelium (lining of glands and ducts)

19. Simple columnar epithelium (lining of stomach, intestines)

20. Stratified squamous epithelium (skin)

21. Simple columnar epithelium (lining of digestive tract)

22. Simple cuboidal epithelium (lining of ducts in kidneys)

23. Simple squamous epithelium (lining of the heart)

24. Pseudostratified columnar epithelium (lining of nasal cavity)

25. Transitional epithelium (urinary bladder)

26. Stratified squamous epithelium (lining of mouth)

27. Type of TissueFunctionLocation Pseudostratified columnar removing dust and particles from airways, has cilia lines the respiratory passageways Simple ColumnarAbsorption lines the uterus and most organs of the digestive tract Simple CuboidalSecretion and Absorption glands, kidney tubules, ovaries Simple SquamousDiffusion and Filtration lungs, walls of capillaries and vessels Stratified SquamousProtects underlying cells skin(keratinized) and the throat, vagina, mouth (soft)keratinized Stratified CuboidalProtection lines ducts of the mammary glands, sweat glands, pancreas Stratified ColumnarProtection, secretion male urethra and vas deferens, parts of the pharynx Transitional (unstretched) Specialized to become distended distended urinary tract