1. TISSUE TYPES

2. TISSUE TYPES
We define “tissue” as “groups of cells that are similar in structure or function”. There are 4 main types of tissue.

3. EPITHELIAL TISSUE Makes up linings, coverings, and glandular tissue
Primary functions include absorption, filtration, and secretion
Cells have no direct blood supply, they instead depend on diffusion from connective tissue capillaries

4. EPITHELIAL TISSUE
One free edge exposed to the exterior of the body or interior of a body cavity is called the apical surface.
Bottom edge bordering basement membrane is called basal surface.
The basement membrane is a structureless material secreted by cells

5. EPITHELIAL TISSUE
We categorize epithelial tissue based off of 2 factors:
Relative number of layers
The shape of the cells

6. SIMPLE EPITHELIAL TISSUE
Simple Epithelial Cells have one layer of cells and their functions include: absorption, secretion, filtration
Simple Squamous Epithelium
Forms membranes where rapid exchange of substance occurs
Air sacs in lungs, capillaries
Simple Cuboidal Epithelium
Found mainly in glands and ducts
Simple Columnar Epithelium
Houses goblet cells that secrete mucous
Lines the digestive tract

7. STRATIFIED EPITHELIAL TISSUE
Stratified Epithelial Tissue is 2 or more cell layers thick, and is mainly used for protection
Stratified Squamous Epithelium:
Most common. Usually several layers of cells.
Found in areas that get a lot of friction or abuse
Around the mouth, esophagus, and outer layer of the skin
Stratified Cuboidal & Stratified Columnar Epithelium:
Found in the ducts of large glands
Rare

8. EPITHELIAL TISSUE Endocrine Exocrine
Transitional Epithelium Cells form organ linings, and can stretch an slide past each other so organs can change shape.
Glandular Epithelium Cells make up your glands.
Endocrine Glands secrete hormones directly into the blood stream
Exocrine Glands secrete into ducts that go to the surface, like sweat and tears.
Endocrine
Exocrine

9. CONNECTIVE TISSUE Connects body parts
Most abundant tissue in the human body
Extremely well vascularized
Made up of different cell types and varying amounts of extracellular matrix

10. CONNECTIVE TISSUE
The Extracellular Matrix is made up of extracellular molecules secreted by cells, providing structure and biochemical support to the cells around it.

11. CONNECTIVE TISSUE Blood Bone
There are 5 main types of connective tissue
Bone
Dense Connective Tissue
Cartilage
Loose Connective Tissue
Blood

12. CONNECTIVE TISSUE BONE
Cells sit in lacunae cavities surrounded by a hard matrix of calcium and collagen fibers

13. CONNECTIVE TISSUE Cartilage Less hard and more flexible than bone
Hyaline Cartilage
Elastic Cartilage
Fibrocartilage

14. CONNECTIVE TISSUE Dense Connective Tissue
Matrix of collagen fibers with rows of fibroblasts
Tendons (muscle to bone)
Ligaments (bone to bone)

15. CONNECTIVE TISSUE
Loose Connective Tissue – soft, with more cells and less fibers
Adipose Tissue – used for fuel, insulation, and forms subcutaneous tissue beneath the skin
Areolar Tissue – cushions and protects body organs, keeps them in place, and connects skin to muscle

16. CONNECTIVE TISSUE Blood Transport for cardiovascular system
Transports oxygen
Transports white blood cells from bone marrow

17. Muscular Tissue Skeletal Muscle Long and striated
Used for voluntary movement
Can have multiple nuclei

18. Muscular Tissue Cardiac Muscle Heart only
Striated, branching cells that interlace and are filled with gap junctions that help ion movement for rapid electrical flow

19. Muscular Tissue Smooth Muscle No striations Only one nucleus
Lines hollow organs
Helps with motion

20. Muscular Tissue

21. NERVOUS TISSUE
NEURONS receive information (stimulation) and send information (reaction)

22. NERVOUS TISSUE
The Spinal Cord runs inside the vertebral column and is very heavily protected by both bone and fluid to keep it safe and absorb impact. All the nerves in the body stem from the spinal cord.

23. NERVOUS TISSUE

24. NERVOUS TISSUE
The brain is the control center for the nervous system, regulating and controlling everything the body does.
It is also where all your memories are stored.

25. Nervous Tissue is also responsible for the regulation of TISSUE REPAIR

26. NERVOUS TISSUE Tissue Repair, Stage 1 - Inflammation
Swelling of tissue
Feeling of warmth
Pain and redness while repair starts
Area flooded with blood to deliver white blood cells
White blood cells destroy and remove unrepairable cells and bacteria in the area

27. NERVOUS TISSUE Tissue Repair, Stage 2 - Regeneration
Mitotic rate increases
New cells put in place
Begins while cleanup is still in process
Initial repair done by fibroblasts
Fibroblasts lay down collagen fibers to stabilize tissue

28. NERVOUS TISSUE
PUS
When a foreign body is detected (like bacteria) and an infection starts, the body signals for NEUTROPHILS (fast-acting white blood cells) to attack. Bacteria fights back, killing off neutrophils as they attack. Pus is an accumulation of dead neutrophils.