1. In biology, a lumen (from Latin lumen, meaning 'an opening'; plural lumina) is the inside space of a tubular structure, such as an artery or intestine.

2. Cilia are found on ciliated epithelial cells, like in the lungs
Cilia are found on ciliated epithelial cells, like in the lungs. They wave rhythmically to move dirt and mucus out.
Microvilli are found in the small intestine, and increase the surface area for nutrient absorption.
The difference between cilia and microvilli is that microvilli help in absorption whereas cilia help in rhythmic movement (sweeping).

3. Unit 2: Tissues

4. Unit 2: Tissues
Tissue: a group of cell types working together for the same purpose

5. Unit 2: Tissues
Tissue: a group of cell types working together for the same purpose
4 Types of tissues

6. Unit 2: Tissues
Tissue: a group of cell types working together for the same purpose
4 Types of tissues
Epithelial
Connective
Muscle
Nervous

7. Epithelial Tissues

8. The following types of epithelial tissues are covered in this activity:
1. Simple squamous epithelial tissue (lungs)
2. Simple cuboidal epithelial tissue (kidneys)
3. Simple columnar epithelial tissue (small intestine)
4. Pseudostratified (ciliated) columnar epithelial tissue (trachea lining)
5. Stratified squamous epithelial tissue (mouth lining)
6. Stratified cuboidal epithelial tissue (salivary glands, sweat glands)
7. Stratified columnar epithelial tissue (male reproductive tract)
8 Transitional epithelial tissue (bladder)
a. The tissue may show a full bladder
b. The tissue may show an empty bladder

9. Figure 4.3e Epithelial tissues.
(e) Stratified squamous epithelium
Description: Thick membrane
composed of several cell layers;
basal cells are cuboidal or columnar
and metabolically active; surface
cells are flattened (squamous); in the
keratinized type, the surface cells are
full of keratin and dead; basal cells
are active in mitosis and produce the
cells of the more superficial layers.
Stratified
squamous
epithelium
Function: Protects underlying
tissues in areas subjected to abrasion.
Nuclei
Location: Nonkeratinized type forms
the moist linings of the esophagus,
mouth, and vagina; keratinized variety
forms the epidermis of the skin, a dry
membrane.
Basement
membrane
Stratified squamous epithelium is a type of tissue that makes up skin layers and lines some body cavities and organs. Its structure makes it an excellent protective layer. Many layers piled on top of each other to make the tissue relatively thick. The cells divide in the deeper layers and newer cells push older ones further outward where they become flattened. Locations: Skin, Oral Cavities, Esophagus, Vagina, Anal Cavity. They form the outer layer of the skin called the epidermis. As skin cells age they accumulate the protein keratin and then harden and die. The keratin creates a dry tough protective material that prevents water and other material from entering. When not on the skin, the cells DO NOT produce keratin and remain smooth and soft.
Connective
tissue
Photomicrograph: Stratified squamous epithelium
lining the esophagus (285x).

10. several layers of elongated cells. The basal layers are cube shaped
several layers of elongated cells. The basal layers are cube shaped. Found in the male urethra and vas deferens, and in parts of the pharynx

11. Consist of two or three layers of cuboidal cells that form the lining of the lumen. Lines the larger ducts of the mammary glands, sweat glans, salivary glands, and pancreas. Lining of the ovarian follicles and seminiferous tubules which are part of the male and female reproductive systems

13. Figure 4.3f Epithelial tissues.
(f) Transitional epithelium
Description: Resembles both
stratified squamous and stratified
cuboidal; basal cells cuboidal or
columnar; surface cells dome
shaped or squamouslike, depending
on degree of organ stretch.
Transitional
epithelium
Function: Stretches readily and
permits distension of urinary organ
by contained urine.
Several layers of the cuboidal cells. Changes in response to tension. Stretched and not stretched in response to tension. Provides expanded lining. Prevents contents of the urinary tract from diffusing back into the internal environment. Location in the urinary bladder, uterus, urethra
This tissue is transitional, meaning it doesn't stay the same shape for long, as it transitions from one shape to another as necessary. In simple terms, transitional epithelial tissue is an elastic-like epithelial tissue that swells, contracts, and changes shape as necessary in order to accommodate something.
One of the places this tissue is found is in your bladder. When your bladder is empty, the transitional cells look to be cuboidal in shape. However, as the bladder fills up, the urine in the bladder stretches the bladder walls, which stretch out the cuboidal cells and cause them to become flat, or squamous in shape, instead.
Location: Lines the ureters, urinary
bladder, and part of the urethra.
Basement
membrane
Connective
tissue
Photomicrograph: Transitional epithelium lining the urinary
bladder, relaxed state (360X); note the bulbous, or rounded,
appearance of the cells at the surface; these cells flatten and
become elongated when the bladder is filled with urine.

14. Given the previous examples (consider the morphology only)
Can you name?
First, the tissue type
Second, where in the body the tissue is found

15. What kind of tissue does this represent?
Stratified squamous epithelial tissue
Where in the body would you find this tissue?
mouth lining

16. What kind of tissue does this represent?
Stratified cuboidal epithelial tissue
Where in the body would you find this tissue?
salivary glands, sweat glands

17. What kind of tissue does this represent?
Stratified columnar epithelial tissue
Where in the body would you find this tissue?
male reproductive tract

18. What kind of tissue does this represent?
Transitional epithelial tissue
Where in the body would you find this tissue?
empty bladder

19. What kind of tissue does this represent?
Transitional epithelial tissue
Where in the body would you find this tissue?
distended (full) bladder

20. Epithelial tissue is characterized by each of these traits, except that… 
a) It lacks blood vessels
b) It functions in secretion, absorption, and excretion
c) Epithelial cells are loosely packed and have much intercellular material
d) It is anchored to a basement membrane

21. Microvilli, which function to increase surface area, are more likely to be found in ____________ epithelium
simple cuboidal
Simple squamous
Transitional
Simple columnar

22. Epithelium that appears layered due to the varying levels at which nuclei are found in cells, but in reality is not layered, is _________________.
Transitional epithelium
Pseudostratified Columnar Epithelium
Stratified Squamous Epithelium
Stratified Columnar Epithelium

23. The outer layer of the skin is composed of…
Transitional epithelium
Pseudostratified columnar epithelium
Stratified squamous epithelium
Stratified Columnar epithelium

24. Thickening of the basement membrane
The primary purpose of stratification, or layering, in epithelial tissue is for increased _____________.
Protection
Secretion
Absorption
Thickening of the basement membrane

25. What type of epithelium lines the urinary bladder?
stratified cuboidal epithelium
Stratified squamous epithelium
Transitional epithelium
Stratified columnar epithelium

26. Under Epithelial classification simple equals how many layers?
None
One
Multiple

27. Epithelial tissue is avascular. 
A. True
B. False

28. Under epithelial classification squamous equates to what shape?
A. Flat
B. Wide and tall
C. Tall and skinny

29. Epithelial tissue is polar.
A. True
B. False