1. Chapter 4: Tissues
The Living Fabric

2. Tissues: A grp of cells that perform the same function Differ in:
Size & shape
Amt & kind of matrix (stuff btw the cells)
Functions they perform

4. Tissues are held together by intercellular junctions
Gap junctions
Desmosomes
Tight junctions

5. Embryonic Dvlpt:
The 4 major tissues of the body appear in the 1st 2 months after conception of the embryonic period
After fertilization, the zygote will begin cont. cell divisions to form a blastocyst (hollow ball of cells)

6. The blastocyst implants in the uterus, where in 2 wks the cells will move & regroup into the 3 primary germ layers – gastrulation – the layers are:
a.) endoderm – becomes the inner organs
b.) mesoderm – becomes the muscles
c.) ectoderm – becomes the skin & nervous system

8. 4 Types of Tissues Epithelial – covers the body & lines body cavities
Packed close together w/ little matrix
Divided into membranous & glandular
Functions are:
Protection d.) Absorption
Sensory e.) Excretion
Secretion

9. Types: Membranous – classified according to:
shape
a.) squamous – squiggly shaped cells
b.) cuboidal – cube shaped cells
c.) columnar – column shaped cells
d.) pseudostratified columnar – 1 layer of odd shaped cells

10. Arrangement a.) simple – 1 layer of the same shape
b.) stratified – many layers of the same shape
c.) transitional – several layers of diff shaped cells

12. Types of Epithelial Tissue:
Simple Squamous Epithelium
Simple Cuboidal Epithelium
Simple Columnar Epithelium
Pseudostratified Columnar Epithelium
Stratified Squamous Epithelium
Stratified Cuboidal Epithelium
Stratified Columnar Epithelium
Transitional Epithelium
Glandular Epithelium

13. Glands!!!
Consists of 1 or more cells that make & secrete a particular product
Classified as:
Endocrine – internally secreting – ex.) hormones
Exocrine – externally secreting – more numerous – diverse in their product – ex.) mucus, milk, sweat, oil

14. Exocrine contains: Apocrine – milk producing mammary glands
Holocrine – oil glands
Merocrine – salivary glands

16. 4 Types continued…
2. Connective Tissue – most abundant & widely distrib - many types, appearances & functions - few matrix cells – contains 1 or more A.) collagenous fibers – tough B.) reticular fibers – delicate C.) elastic fibers - extensible

18. Functions are:
Connects
Supports
Transports
Defends

19. - Types of connective tissue:
A.) Loose, ordinary (areolar) – contains: 1.) areolar – “glue” that holds organs together – area btw other tissues & organs 2.) adipose – “fat” – under the skin – used for padding & insulation 3.) reticular – 3-D web – filters harmful substances out of the blood & lymph 4.)dense fibrous – tendons, scars, ligaments, fascia, & dermis

21. B. )Bone – calcified matrix – support & protection C
B.)Bone – calcified matrix – support & protection C.) Cartilage – matrix has the consistency of firm plastic or gristle-like gel – nasal septum, trachea rings D.) Blood – fluid matrix - transportation

23. 4 Types continued….
3. Muscle Tissue – 3 types a.) Skeletal Muscle – - attached to bones - striated voluntary - striations are visible b.) Cardiac Muscle – - striated involuntary - compose heart wall

24. C.) Smooth Muscle – - nonstriated (visceral) or involuntary - no cross striations - found in blood vessels & other tube shaped organs

26. 4 Types cont….
4.) Nervous Tissue – rapid communication btw body structures & control of body functions
- 2 cell types
a.) Neurons – conducting cells
- composed of:
1.) cell body
2.) one axon – carries impulses away from cell body
3.) 1 or more dendrites – carries nerve impulses toward the cell body
b.) Neuroglia – supports & connects neurons

28. Tissue Repair: usually accomplished by means of regeneration of tissue
epithelial tissues readily regenerate collagen fibers to fill gaps
connective tissue also regenerates
muscle & nerve tissues have very limited abilities to repair themselves
spinal cord damage results in permanent disability

29. Inflammatory Response:
Redness
Swelling
Pain
Heat
***Can determine if tissue will regenerate

30. Tissue Regeneration

31. See Handout!!!!
Tumors

32. Tumors of the Tissues:

33. Cancers of the Tissues: