1. Ch. 5: Tissues!!

2. Let’s create a beating heart

3. Objectives
To explain the difference between different kinds of tissues
To identify the types of epithelial tissue
To list the locations of each type of epithelial tissue

4. Do Now!!  What is the definition of a tissue?
What are some functions of tissues?
Where are some locations in the body where you can find tissues?

5. Important Terms Histology: The study of tissues
Tissues: Groups of specialized cells which are similar in structure and perform common functions

6. 4 Types of Tissues Epithelial Connective Muscle Nervous
Make some observations!
Epithelial
Connective
Muscle
Nervous

7. 4 Types of Tissues (cont.)
Epithelial:
Form protective coverings
Function in secretion, absorption and diffusion
Connective:
Provide support and protection
Bind structures together
Muscle:
Produce body movements
Nervous:
Control and coordinate body activities
* Most organs contain all 4 types

8. Epithelial Tissue Forms covering of body surfaces
Lines body cavities, organs, tubes, ducts, blood vessels
Major tissue in glands
Covers organs

9. Epithelial Tissue (cont.)
Functions:
Protection from physical/chemical injury and invasion
Secretion, filtration and reabsorption of materials
Secretion of serous fluids to lubricate structures
Diffusion
Sensory reception

10. Do Now!  How is the structure of a tissue related to its function?
Epithelial tissue is categorized based on 2 properties. Hypothesize what those 2 properties could be.

11. Epithelial Tissue Factoids
One free surface always exposed to the outside or open internal space: apical surface
Attached to basement membrane on the other side
Tightly packed
Avascular: NO blood vessels!! Rely on diffusion from underlying connective tissue
Divides rapidly
Classified according to
top layer of cells

12. Classes of Epithelia (Layers)
Stratified: multiple layers
Simple: just one layer

13. Classes of Epithelia (Shape)
Squamous: squashed (thin and flat, like an egg)
Ex: Endothelium (lines blood vessels) and mesothelium (lines pleural, peritoneal and pericardial cavities)
Columnar: columns
Ex: Lining of gut tube; sometimes with cilia like lining
Cuboidal: cubed (square shaped)
Ex: Walls of glands

15. Squamous Simple Diffusion and filtration
Ex: alveoli, capillary walls, lines blood and lymph vessels
2. Stratified Squamous
Physical protection against abrasion
Protection against pathogens
Ex: Epidermis, oral cavity, esophagus, vagina and anal canal

16. Squamous (cont.) 3. Keratinized Stratified Squamous:
Aging skin cells produce keratin, harden then die
“keratinization”: produces dry, tough, protective covering
layers of dead squamous cells
prevents water/substance loss
barrier to organisms

17. Columnar 1. Simple Columnar provides some protection
cells can be ciliated or non-ciliated
absorption/secretion
usually contain “goblet” cells
Ex: Uterus, most organs of digestive tract
2. Stratified Columnar
- *rare
secretion/absorption
- Ex: small portion of male urethra

18. Columnar (cont.) 3. Pseudostratified Ciliated Columnar
- Appears stratified
- All cells touch basement membrane and have exposed end
Ex: passageway of respiratory system

19. Cuboidal Simple Cuboidal secretion/absorption secretes sweat
line ducts
Ex: ovaries, kidney tubules, ducts of glands (salivary, thyroid, pancreas and liver)
2. Stratified Cuboidal
*rare
usually only 2-3 layers
Larger ducts of glands
Ex: mammary glands, sweat glands,
Salivary and pancreas

20. Transitional Stratified Tolerates repeated stretching
Ex: bladder, ureters, and urethra

22. Can You Identify the Classes of Epithelium?
Quiz!! E
Can You Identify the Classes of Epithelium? D A B C

23. Slides
Simple Squamous
*Lung

24. Slides
Simple Cuboidal
*Kidney

25. Ciliated Pseudostratified Columnar
Slides
Ciliated Pseudostratified Columnar
*Trachea

26. Slides
Stratified Cuboidal
*Sweat gland duct

27. Slides
Simple Columnar
*Small intestine

28. Slides
Stratified Squamous
*Skin

29. Slides
Transitional
*Bladder

30. Glands
Glandular Epithelium: cells that produce and secrete chemical substances
Exocrine Glands
Secrete substance onto body surface or into body cavity
Have ducts
Ex: salivary, mammary, pancreas, liver, sweat, mucous

31. Glands (cont.) Endocrine Glands Secrete product into blood stream
Hormones travel to target organ to increase response
No ducts
Ex: pancreas, thyroid, hypothalamus, adrenal, testes, ovaries

32. Types of Glands
Merocrine: release watery, protein-rich fluids by exocytosis
Ex: salivary and pancreas glands
Apocrine: lose small portions of their cell bodies
Ex: mammary glands
Holocrine: entire cell filled with secretory products lyses
Ex: sebaceous glands

33. 1.
Epithelial! 2.
Connective!