1. Body Tissues and Wound Regeneration
Anatomy Unit 3

2. 4 Primary Types of Tissues
Groups of cells that are similar in structure and function are called TISSUES
4 Primary Types of Tissues
Epithelium
Connective Tissue
Nervous Tissue
Muscular Tissue

3. Basic Functions of Tissues
Covering – Epithelium
Support – Connective
Movement – Muscle
Control – Nervous

4. Epithelial Tissue Epithelial Tissue or Epithelium
Lining Covering and Glandular Tissue
Covers all free body surfaces and have versatile cells
Functions include:
Protection
Absorption
Filtration
Secretion
Examples:
Skin epithelium protect against bacterial and chemical change
Epithelium of the lungs has cilia to sweep dust and debris away from lungs

5. Special Characteristics of Epithelium
Most glandular epithelium fit closely together forming continuous sheets
Neighboring cells are bound at many points
Membranes have one free surface or edge called an apical surface
Apical surface is exposed to the body’s exterior or cavity of an internal organ
Lower surface of epithelium rest on a basement membrane
Basement Membranes- structure-less material secreted by both epithelial cells and connective tissue cells
Epithelial tissues have no blood supply
Well nourished epithelial cells may regenerate

6. Classification of Epithelium
Epithelium names
1st – give a number
Simple – one layer
Stratified – multiple layers
2nd – describe the shapes of the cells

7. Simple Squamous Epithelia
Simple Squamous Epithelium – a single layer of thin squamous cells on a basement membrane
Usually form membranes for filtration or exchange of substances by rapid diffusion
Ex:
found in Air sacs in Lungs – where carbon dioxide and oxygen exchange
Capillaries where nutrients and gases pass between tissues and blood
Form Serous Membranes, or Serosae

8. Simple Cuboidal Epithelium
One layer of Cuboidal Cells on a basement membrane
Commonly found in glands and ducts
Forms walls of the kidney tubules and covers the surface of ovaries

9. Simple columnar Epithelium
Single layer of tall cells that fit closely together
Goblet cells- produce a lubricating mucus
Line the entire length of the digestive tract from stomach to the anus
Found in membranes that line body cavities open to the body exterior
Called mucosae or mucous membranes

10. Pseudostratified Columnar Epithelium
Pseudostratified Columnar cells rest on a basement membrane
Some cells are shorter than others and their nuclei appear at different heights above the basement membrane
Gives a false impression that it is stratified
Mainly functions in absorption and secretion

11. Stratified Epithelial Cells
Consist of two or more layers of Epithelial Cells
More durable that Simple Epithelial Cells
Function primarily to protect

12. Stratified Squamous Epithelium
Stratified Squamous Epithelium are the most common stratified epithelium in the body
Usually consists of several layers of cells
Free edge cells are squamous cells, those closer to the basement are cuboidal or columnar
Found in sites that receive a good deal of abuse or friction
Example esophagus, the mouth, and outer portion of the skin

13. Stratified Cuboidal and Stratified Columnar
Stratified Cuboidal Epithelium typically have 2 layers with at least the surface yare being cuboidal in shape
Stratified Columnar Epithelium are columnar cells, but its basal cells vary in size and shape
Both the stratified cuboidal and stratified columnar are rare in the body and found mainly in the ducts of large glands

14. Transitional Epithelium
Transitional epithelium is a highly modified, stratified squamous epithelium that forms the lining of only a few organs
Urinary bladder, ureters, and urethra
Cells of the basal layer are cuboidal or columnar, and those at the free in vary in appearance
Cells are able to slide past one another and change shape

15. Glandular Epithelium
Glands- consist of one or more cells that make and secrete a particular product (secretion)
Two major types of glands:
Endocrine Glands- Loose connection to the surface
Also known as Ductless Glands
Secretions diffuse directly blood vessels weaving through the gland
Exocrine Glands- retain their duct
Secretions empty through ducts directly on the epithelial surface

16. Connective Tissue Connective Tissue – connects body parts
Found everywhere in the body
Most abundant and widely distributed of the tissues
Have variations in blood supply and have an extracellular matrix
Common types of connective tissue:
Bones
Cartilage (especially Hyaline Cartilage)
Dense and Loose Connective Tissue
Adipose Tissue
Reticular Tissue

18. Muscular Tissue
Muscular Tissue – Highly specialized to contract (shorten) to produce movement
3 Types of Muscular Tissue
Skeletal Tissue – packaged by connective tissue which attach to the skeleton.
Can be controlled voluntarily
When they contract pull on the bones or skin and cause movment
Cardiac Muscle – is found only in the heart
As the muscle contracts the heart pumps
Smooth Muscle – has not visible striations
Long cells, found in walls of hollow organs like the stomach, uterus, blood vessels etc.

20. Nervous Tissue makes us think of neurons
Neurons receive and conduct electrochemical impulses from one part of the body to another
Irritability and Conductiveness are mayor resources

21. Tissue Repair
Wound Healing

22. Injury to tissue occurs…
Tissue repair has two major responses
Regeneration
Fibrosis
3 Steps:
Inflammation sets the stage for injured cells allow for fluids and clotting proteins to take affect
Granulation Tissue Forms- is the delicate pink tissue composed of new capillaries that grow into the damaged area and dispose of the blood clot formed earlier.
Regeneration and Fibrosis cause permanent repair