1. Connective Tissue Most common tissue found in body
Can be delicate-thin, tough-rigid or fluid
Main Functions
Connect
Muscle to muscle
muscle to bone
Bone to bone
Supports
Framework for body and organs
Transports
blood
Defends
Protects against microorganisms

2. Connective Tissue Characteristics
Matrix-intercellular material, fibers
Ground substance, provides medium for exchange of substances
components of matrix and ground tissue define the type of tissue
Highly vascular and innervated (not all)
Mesenchyme- tissue in embryo that all other connective tissue arises from

3. Types of Fibers Fibroblasts create these protein fibers
Collagen (white fibers) most common protein in body
Tough and strong
Occur in bundles
Hydrated form known as gelatin
Reticular
Special type of collagen, reticulin
Occur in bundles yet are delicate
Supports capillaries and nerve fibers
Elastic fibers
Retains shape after being stretched
Made from protein elastin
Found in stretchy tissue such as the external ear
Proteoglycans
Made of polysaccharide chains containing glucosamine
Thicken the matrix to create barrier against bacteria/microbes
Transparent lubricant that hold tissue together

4. Classification of Connective Tissue
Fibrous (loose)
Areolar (ordinary)
Adipose
Reticular
Dense
Bone
Cartilage
Hyaline
Fibrocartilage
Elastic
Blood

5. Areolar(loose ordinary)
Elastic glue that permits movement
Stretchable and very common
Matrix is soft thick gel, contains hyaluronidase
Hyaluronidase is an enzyme that can change thick gel matrix to watery state
Contain interwoven fibers of collagen and elastin
Main types of cells
Fibroblasts- synthesizes ground substance and fibers
Macrophages(histiocytes)- carry on phagocytosis
Mast cells- wandering white blood cell
Fat & plasma cells

6. Areolar(loose ordinary)

7. Adipose Tissue Mainly fat cells
Few fibroblasts, mast cells and macrophages
Cushions organs
Stores excess energy
Conserves body heat

8. Adipose Tissue

9. Reticular Tissue 3 dimentional meshwork of reticular fibers
Defense against microorganims and injurious substances
Filters toxic substance out of blood and lymph
Framework for spleen, lymph nodes and bone marrow

10. Reticular Tissue

11. Dense Fibrous Tissue Fibers are densely packed in matrix
Bundles of collagen fibers
Flexible but very strong
Regular is parallel fibers
Tendons(muscle to bone)
Ligaments, more elastin (bone to bone)
Irregular (wavy) dense tissue withstands stress from any direction
Forms dermis
Outer capsule of kidneys & spleen
Dense Fibrous Irregular

12. Dense Fibrous Tissue
Dense Fibrous Regular

13. Bone (osseous tissue) Characteristics Osteocytes- mature bone cells
Matrix contains mineral salts and collagen
Mineral salts are responsible for hardness of bone
Ostecytes are trapped in small spaces called lacunae
Haversian canals allow blood vessels to bring nutrition to cells
Functions
Protection
Movement
Mineral storage
Create blood cells

14. Bone Tissue

15. Cancellous Bone (spongy bone)
Ossified Bone (hard bone)

16. Cartilage Tissue Characteritics
Chondrocyte- only type of cell in cartilage
Chondrocyte produce tough fibers and ground substance
*Chondrocyte found in lacunae
Avascular and no nerves
Substances must diffuse through connective tissue surrounding cartilage called perichondrium

17. Types of Cartilage Hyaline(greek for glass) Low amounts of collagen
Shiny translucent appearance
Found in respiratory rings end of bones

18. Hyaline Cartilage

19. Types of Cartilage Fibrocartilage Strongest type of cartilage
Densely packed with white collagen
Shock absorbers
Intevertebral discs and knee joints

20. Intervertebral Disc

21. Fibrocartilage
400X
Dense Fibrous Connective
100X

22. Types of Cartilage Elastic Cartilage Very little collagen
Many very fine elastin fibers
Highly flexible
External ear, voice box, layrnx
“Hairier” that hyaline

23. Elastic Cartilage

24. Blood Tissue Has neither ground substance nor fibers
Exists in liquid state, plasma
Erythrocytes- red blood cells
Leukocytes- white blood cells
Thrombocytes- platelets
Moves gases, nutrients & wastes
Hematopoietic tissue- blood forming tissue

25. Blood Tissue

26. Muscle Tissue High degree of contractility
Provide movement and produce heat
Skeletal (striated voluntary)
Smooth (non striated involuntary or visceral)
Cardiac (striated involuntary)

27. Skeletal Muscle

28. Skeletal Muscle

29. Smooth Muscle

30. Smooth Muscle

31. Smooth Muscle

32. Cardiac Muscle

33. Cardiac Muscle

34. Nerve Tissue Functions Structures
Regulates and integrates body functions
High conductivity and excitability
Structures
Neurons
Neuroglia (supporting cells)
Brain, spinal cord, nerves

35. Nerve Tissue

36. Histology Review Website