Tissue: Fabric of Life

1. Tissue: Fabric of Life Read & Review Chapter 4

2. Body Tissues • Histology- study of biology of tissues • tissues are cells organized for a specific function

3. Development of Tissues • Primary Germ Layers • the process of forming 3 germ layers is called gastrulation • the process of the germ layers differentiating into tissues is called histogenesis

4. Tissue development • Endoderm – innermost layer • ex. Lining of digestive and respiratory organs, thyroid • Mesoderm - middle layer • ex. muscle, skeleton, blood, skin, connective tissue, excretory and reproductive organs • Ectoderm – outermost layer • ex. skin, nervous, epidermis tissue

5. Tissues • Groups of cells that are similar in structure and function • Four primary tissue types 1. Epithelial 2. Connective 3. Muscle 4. Nervous Covering Support Movement Control

6. II. Epithelial Tissues A. 2 Main Types 1. Membranous epithelium- lining/ covering 2. Glandular epithelium- secreting

7. Protection- ex. skin Sensory- ex. skin, nose, eye, ear Secretion- ex. hormones, digestive juices, sweat Absorption- ex. small intestine, lungs Excretion- ex. urine, sweat Epithelial: Functions

8. C. Characteristics 1. limited extracellular space (matrix); cells appear tightly packed 2. apical surface (free surface exposed to the body exterior or the cavity of an internal organ) & basement membrane (bottom surface connected to connective tissue)

9. Characteristics-(Continued) 3. avascular- no blood vessels; uses diffusion instead 4. innervated- contains nerve fibers 5. origin is ectodermal, mesodermal, endodermal 6. high regeneration capacity

10. D. Classification of membranous epithelial 1. Cell Shapes a. Squamous- flat, round b. Cuboidal- cubed c. Columnar- narrow cylinder d. Pseudostratified- one layer of odd-shaped columnar cells; appears to be more than one layer

11. Layers of Cells Layers of Cells a. Simple- single layer b. Stratified- more than one layer

12. 3. Cell Shapes & Layers of Cells a. simple squamous- ex. alveoli in lungs b. simple cuboidal- ex. glands, kidney c. simple columnar- ex. golbet cells, cilia, microvilli

13. Simple Squamous Epithelium • Absorption • Secretion • Filtration

14. Glands, ducts Walls of the kidney tubules Surface of the ovaries Simple Cuboidal Epithelium

15. Simple Columnar Epithelium Goblet cells secrete mucus that aids in the function of respiratory system

16. Pseudostratified columnar ex. goblet cells, respiratory • All the cells rest on the basement membrane • Since some of the cells are shorter then others, the nuclei appear at different heights

17. Stratified Squamous (keratinized and non-keratinized) • Stratified Squamous Epithelium: Most common stratified epithelium in the body • Squamous at the free edge and columnar or cuboidal at the basement membrane • Sites of abuse or friction: esophagus, mouth and outer portion of the skin, the outer surface of skin is keratinized (surface cells contain keratin, a tough protective protein)

18. Keratinized vs. Nonkeratinized

19. Stratified Cuboidal • Stratified Cuboidal and Columnar Epithelium usually just two cell layers • Fairly rare in the body; mainly ducts of large glands • Sweat glands • Mammary glands

20. Transitional Epithelium • highly modified stratified squamous: urinary bladder, ureters, urethra. • All these organs are part of the urinary system and are subject to considerable stretching

21. -ac, -al, -ary, -ic, -tic, -ous: pertaining to/related to -ad: derived from -algia: pain -cele: hernia -centesis: puncturing -ectomy: cutting out -iasis: a process or its results -itis: inflammation -ium: diminuitive, small -ize: to make into -lysis: break down -oid: resembling, like -oma: tumor/cancer -osis: denotes states or condition -ous: possessing, full of -plasty: molding, forming -rrhea: flow -sect: to cut, divide -sia, -sis, -tion, -y: action/condition -stomy: make an artificial opening -tomy: to cut Section 2 vocab: common suffixes

22. Three Week Schedule 9/8- Gladular Epithelial tissue; Scope Work 9/9- Quiz (Epithelial tissue); Connective Tissue & Muscle tissue 9/10- Scope Work (Sub day) 9/11- Nervous Tissue; Scope Work 9/12- Vocab quiz (2); Microscope work (no lecture) 9/15- Integumentary Notes, Scope work 9/16- Integ. Notes, Tissues Review, Scope work 9/17- Tissue Practicum Quiz,Tissue Packet Due 9/18- Finish Integ Notes; Lab activity 9/19- Vocab Quiz (3), Disease & Disorder Lecture (End 1st 6 wks) 9/22- Review for Test 9/23- Tissue/IntegumentaryTest 9/24- Bones/Skeletal Lecture 9/25-Bones Discussion and Identification 9/26- Vocab Quiz (5), Bones Lab

23. Glandular Epithelium • Gland: one or more cells that make and secrete a product • Secretion: protein molecule in aqueous fluid [some secrete a lipid or steroid rich secretion]

24. Classification of glandular epithelial tissue 1. Cell Number a. Unicellular glands- single cells ex. goblet cells- mucus b. multicellular glands- clusters of cells; ex. mammary ducts- milk

25. Classification of glandular epithelial tissue 2. Discharge method • Exocrine glands – secrete into duct ex. saliva, sebaceous, mammary, sweat • Endocrine glands - ductless; secrete hormones into bloodstream ex. pituitary gland, thyroid, ovary, testes, adrenal, pancreas

26. Glandular Epithelium • Endocrine: ( internal secreting) • ductless; all hormone secretions directly into the blood or lymphatics (secrete by the process of exocytosis) • thyroid; adrenals; pituitary

27. Multicellular Exocrine Glands • Two basic parts: • Duct • Secretory unit that consists of secretory cells called acini

28. Modes of secretion • Merocrine glands-exocytosis • (pancreas, salivary glands, sweat glands) • Holocrine Glands-rupture • (Sebaceous oil glands of the skin)

29. Epithelial tissue overview