1. Tissues Chapter 5 Objectives: 1.List and describe the four major tissue types, and provide examples of where each occurs in the body. 2.Name the types of epithelium, and identify an organ in which each is found. 3.Distinguish different types of connective and muscular tissues.

2. Tissue: Def.: a group of similar cells that performs a specialized function 4 major types of tissues:

3. A. Epithelial Tissues Forms linings throughout the body Anchored to underlying connective tissue by a nonliving layer called basement membrane 1. Simple Squamous Epithelium - a single layer of thin, flattened cells – Fit together tightly – Broad, thin nuclei – Substances pass through easily; easily damaged – Found in lung air sacs, capillary walls, and membranes lining body cavities – ???

4. Epithelial Tissues (cont.) 2. Simple Cuboidal Epithelium – single layer of cube-shaped cells – Centrally located, spherical nuclei – Ovaries, kidney tubules, ducts of some glands – Adds in secretion and absorption

5. Epithelial Tissues (cont.) 3. Simple Columnar Epithelium – longer than they are wide (elongated, like columns) – Thicker – Nuclei located near the basement membrane – Ciliated – found in female reproductive tubes – Nonciliated – lining of uterus, stomach, intestines

6. Epithelial Tissues (cont.) 4. Pseudostratified Columnar Epithelium – appear to be stratified (layered), but are not – Why? Nuclei are found at different levels in the cells, instead of only near the basement membrane. – Many are ciliated. – Found lining respiratory passages

7. Epithelial Tissues (cont.) 5. Stratified Squamous Epithelium – Many layers = thick (for protection) ??? – Outer layer of skin (“epidermis”) – Lining of mouth, throat, vagina, and anal canal 6. Stratified Cuboidal Epithelium – 2-3 layers of cuboidal cells lining a lumen – Lines large ducts of glands (mammary, sweat, salivary, pancreas) and of ovarian follicles and seminiferous tubules 7. Stratified Columnar Epithelium – Top layer elongated; base layer cube-shaped – Found in male urethra, vas deferens, and pharynx

8. Epithelial Tissues (cont.) 8. Transitional Epithelium – changes in response to tension – Found lining the bladder, ureters, and part of the urethra – Contracted – thicker; many layers ** – Relaxed – stretches and appears thinner See Table 5.3, p. 99!!