Make some observations about the following picture…
DO NOW
Chapter 5
TISSUES
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.
OBJECTIVES
1. Histology: The study of tissues
2. Tissues: Groups of cells which are similar in structure and perform common functions.
KEY TERMS
4 BASIC TISSUE TYPES
Locations: 1. Covers the body
(skin)2. Lines cavities, tubes,
ducts, blood vessels
3. Covers organs
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
EPITHELIAL TISSUE
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!
EPITHELIUM
What characteristics distinguish the following groups of cells?
CLASSIFYING EPITHELIUM
1. Layersa) simple = 1 layerb) stratified = multiple layers
2. Shapea) squamous: thin/flat (think
“squished”)b) columnar: tall slender
rectangles (columns)c) cuboidal: square shaped (like
cubes)
CLASSIFYING EPITHELIUM
1. Simple Squamous- absorption
Ex:
2. Stratified Squamous- physical protection against abrasion
- protects against pathogens/chemicals
Ex:
SQUAMOUS
3. Keratinized Stratified Squamous
- layers of dead squamous cells- retards water loss- barrier to organisms
SQUAMOUS
1. Simple Columnar- provides some protection
- absorption/secretion
- usually contain “goblet” cells
Ex:
2. Stratified Columnar- *rare
- secretion/absorption
Ex: small portion of male urethra
COLUMNAR
3. Pseudostratified Ciliated Columnar – all cells touch basement membrane
COLUMNAR
Smoking = goodbye cilia
1. Simple Cuboidal- secretion/absorption
- secretes sweat
- produces sperm & hormones
- line ducts
Ex:
2. Stratified Cuboidal- *rare
- usually only 2-3 layers
- ducts of glands
Ex:
CUBOIDAL
Duct
Cuboid Cells
- Stratified- Tolerates repeated stretching- Ex:
TRANSITIONAL
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.
THINK-PAIR-SHARE
1. Take out your cell phones for PollEverywhere!
CLOSING
1. How is epithelial tissue classified? 2. What is the main function of
epithelial tissue?3. Which type of epithelium would you
find in the intestines that contains goblet cells?
DO NOW
1.Identify slides of tissue using the classification of epitheliail tissue.
2.Compare and contrast exocrine and endocrine glands.
3.List and explain the 3 types of exocrine glands.
OBJECTIVES
Decide which type of epithelium is being shown on the slide. Try to determine what tissue/organ this is a slide of.
IDENTIFYING SLIDES
SLIDES
SLIDES
SLIDES
SLIDES
SLIDES
SLIDES
Endocrine: ductless glands (secreted hormones directly into blood stream)
Exocrine: glands contain ducts that connect with surface
GLANDULAR EPITHELIUM
1) Merocrine: release fluid through exocytosis (ex: tears, gastric juices)
2) Apocrine: release part of cell ( ex: axillary glands, mammary glands)
3) Holocrine: release and destroy whole cell. (ex: sebaceous glands)
TYPES OF GLANDS
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.
MICROSCOPE PRACTICE