1. Do Now
Make some observations about the following picture…

2. Tissues
Chapter 3

3. objectives
1. Explain the 4 types of tissues. 2. Identify the different types of epithelial tissue. 3. List the locations of each type of epithelial tissue.

4. Key terms
1. Histology: The study of tissues 2. Tissues: Groups of cells which are similar in structure and perform common functions.

5. 4 basic tissue types

6. Epithelial tissue Locations:
1. Covers the body (skin)
2. Lines cavities, tubes, ducts, blood vessels
3. Covers organs

7. Epithelial tissue Functions:
1. Protection from physical & chemical injury
2. Protection against microbial invasion
3. Contains receptors which respond to stimuli
4. Filters, secretes & reabsorbs materials
5. Secretes serous fluids to lubricate structures

8. Epithelium Facts about Epithelium:
- always have one free surface exposed to the outside or open internal space.
- attached to a basement membrane on the other side.
- tightly packed
- **Avascular- LACK BLOOD VESSELS, rely on diffusion from the underlying connective tissue.
- Divide rapidly!

9. Classifying epithelium
What characteristics distinguish the following groups of cells?

10. Classifying epithelium
1. Layers
a) simple = 1 layer
b) stratified = multiple layers
2. Shape
a) squamous: thin/flat (think “squished”)
b) columnar: tall slender rectangles (columns)
c) cuboidal: square shaped (like cubes)

12. Squamous 1. Simple Squamous 2. Stratified Squamous - absorption Ex:
- physical protection against abrasion
- protects against pathogens/chemicals

13. Squamous
3. Keratinized Stratified Squamous - layers of dead squamous cells - retards water loss - barrier to organisms

14. columnar 1. Simple Columnar 2. Stratified Columnar
- provides some protection
- absorption/secretion
- usually contain “goblet” cells
Ex:
2. Stratified Columnar
- *rare
- secretion/absorption
Ex: small portion of male urethra

15. columnar
3. Pseudostratified Ciliated Columnar – all cells touch basement membrane
Smoking = goodbye cilia

16. cuboidal 1. Simple Cuboidal 2. Stratified Cuboidal
- secretion/absorption
- secretes sweat
- produces sperm & hormones
- line ducts
Ex:
2. Stratified Cuboidal
- *rare
- usually only 2-3 layers
- ducts of glands
Cuboid Cells
Duct

17. Transitional
Stratified
Tolerates repeated stretching
Ex:

18. Think-pair-share
Identify the types of epithelium on your worksheet by yourself. Go over your answers with the person sitting next to you to see if you got similar answers.

19. Closing
Take out your cell phones for PollEverywhere!

20. Do Now How is epithelial tissue classified?
What is the main function of epithelial tissue?
Which type of epithelium would you find in the intestines that contains goblet cells?

21. Objectives
Identify slides of tissue using the classification of epitheliail tissue.
Compare and contrast exocrine and endocrine glands.
List and explain the 3 types of exocrine glands.

22. Identifying Slides
Decide which type of epithelium is being shown on the slide. Try to determine what tissue/organ this is a slide of.

23. slides

24. slides

25. slides

26. slides

27. slides

28. slides

29. Glandular epithelium
Endocrine: ductless glands (secreted hormones directly into blood stream) Exocrine: glands contain ducts that connect with surface

30. Types of glands
Merocrine: release fluid through exocytosis (ex: tears, gastric juices)
Apocrine: release part of cell ( ex: axillary glands, mammary glands)
Holocrine: release and destroy whole cell. (ex: sebaceous glands)

31. Types of Glands Animation

32. Microscope Practice
Please take a slide and a microscope. Go through each of the powers under the microscope, finding the free space that will contain the epithelial tissue. Move the slide accordingly. Call me over to verify that you are looking at the right thing before you move on to the next power.