1. Tissue Notes

2. Types of Tissue 1. Epithelial Tissue - lines all surfaces of the body including organs. Protects, secretes, absorbs, excretes. Ex: outer layer of skin, inside of mouth and stomach, tissue surrounding the body's organs, vessels, ducts. Characteristics of Epithelium All have one exposed surface Lack blood vessels-get nutrients by diffusion Divide rapidly Tightly packed to form barriers Classified by shape and # of layers ShapesLayers Squamous-flattenedSimple-one layer Cuboidal-cube shapedStratified-multiple layers Columnar-column shapedPsuedo-stratified-looks layered

3. TYPES OF EPITHELIAL TISSUE Simple squamous epithelium-One layer, flattened shape, lines air sacs of lungs, capillaries, diffusion occurs easily. Easily damaged.

4. Simple cuboidal epithelium- one layer, cube shaped, covers ovaries, lines ducts of kidneys and other glands. Nuclei are central.(Free surface faces a lumen or hollow channel). Secretes and absorbs.

5. Simple columnar epithelium- One layer, elongated shape, some have cilia, made for absorption, secretion, lines uterus and digestive tract organs. ( contain goblet cells to secrete mucus to protect). Thick tissue protects underlying layers.

6. Pseudostratified columnar epithelium- appear layered but are not. Line respiratory system passages and have cilia to sweep away dust etc. (Goblet cells-also secrete mucus to trap particles). Protects and secretes. Moves things along.

7. Stratified squamous epithelium -thick multi-layered, forms outer layer of skin (which keratinizes-hardens), line oral cavity, esophagus, vagina, and anal canal ( all which are moist and don’t keratinize). Protects.

8. Stratified cuboidal epithelium -lines lareger ducts, salivary and sweat glands, mammary glands, ovarian follicles and seminiferous tubules ( all have lumen). Protects.

9. Stratified columnar epithelium -urethra of males, pharynx. Protects and secretes.

10. Glandular Epithelium -secretes substances into ducts or body fluids. Exocrine glands-secrete products into ducts that open onto surfaces. Example: skin, lining of digestive tract. Endocrine glands-secrete products into tissue or blood.

11. Transitional Epithelium- specialized to change shape in response to increased tension. Found in bladder, urethra, ureters (all stretch and prevent a barrier)

12. 2. Connective Tissue - adds support and structure to the body. Contains fibrous strands of the protein collagen that add strength to connective tissue. Examples: inner layers of skin, tendons, ligaments, cartilage, bone, blood and fat tissue.

13. Types of Connective Tissue Loose connective Dense connective Hyaline cartilage Elastic cartilage Fibrocartilage Bone Blood

14. 3. Muscle Tissue – specialized tissue that can contract. Contains actin and myosin filaments. Examples: Heart muscle, muscles lining digestive canal and muscles throughout your body. Cardiac muscle Smooth muscle Striated muscle

15. 4. Nerve Tissue -nerve tissue that has the ability to generate and conduct electrical signals in the body. Examples: neurons and glial cells