1. Chapter 4: Tissues

2. Tissue- a group of similar cells that combine to perform a common function
Types of tissue:
Epithelial
Connective
Muscle
Nerve
Membranes

3. Epithelial Tissue
Cells that are closely packed with little intercellular material between them
Avascular (without blood vessels)

4. Covering and Lining Epithelium
Covers the body surfaces
Lines the walls of cavities and organs
Categorized on the basis of cell shape and arrangement

5. 3 General Shapes:
1. Squamous- flat
2. Cuboidal- cube-shaped
3. Columnar- cylindrical
Types of Arrangement:
1. Simple- a single layer
2. Stratified- multiple layers

6. Simple Squamous Single layer of flattened cells
Lines inside wall of blood vessels
Forms walls of capillaries and lung air sacs

7. Simple Cuboidal Single layer of cube-shaped cells
Forms walls of ducts in skin glands and kidney tubules

8. Simple Columnar Single layer of cylindrical cells
Lines inside walls of stomach and intestines

9. Stratified Squamous
Multiple layers of cells, with cells along free edge flattened in shape
Superficial layer of skin, mouth and throat

10. Pseudostratified Columnar
Single layer of irregularly shaped cells that appear multiple, often with cilia
Lines inside walls of larynx, trachea, and bronchi

11. Transitional Multiple layers of spherical or irregularly shaped cells
Lines inside walls of urinary bladder and ureter

12. Glandular Epithelium
Closely packed cells that are specialized to manufacture and secrete products
Forms glands
Categorized on how their products are distributed

13. Exocrine Glands
Glands that empty their products into ducts, which channel secretions to the body surface or cavity
Salivary, sweat and oil glands

14. Endocrine Glands
Glands that secrete their products into the extracellular space, where they diffuse into the bloodstream.
Pituitary, thyroid, and adrenal glands

15. Connective Tissue Highly vascular
Composed of widely scattered cells that lie within a large amount of intercellular material which consists of :
Interstitial fluid
Protein fibers:
Collagenous fibers
Elastic fibers
Reticular fibers

16. Connective Tissue Proper
Intercellular material is produced by fibroblasts
Dominated by protein fibers

17. Loose Connective Tissue (Areolar Tissue)
Protein fibers arranged in a loose network, producing a gel-like material
Contains all 3 types of fibers
Macrophages (fight infection)
Provides a structural anchor for body parts

18. Adipose Tissue
Contains specialized fibroblasts called adipocytes or adipose cells which store fat

19. Dense Connective Tissue (Fibers are packed tightly together)
Dense Regular
Connective Tissue
Fibers extend parallel to each other
resists stress & is found in tendons and ligaments
Dense Irregular
Connective Tissue
Fibers branch to form dense matting
found in the deep layer of the skin

20. Dense Connective Tissue

21. Fluid Connective Tissue
Blood and lymph – are collections of cells in a fluid matrix.

22. Supporting Connective Tissues Cartilage
Produced and maintained
by chondrocytes which lie
in chambers called lacunae
Matrix- firm, dense,
intercellular material

23. Hyaline Cartilage Matrix is dominated by chondroitin sulfate
Contain collagen
Located in the upper respiratory tract tubes, ends of bones, and forms the skeleton of the fetus

24. Elastic Cartilage Matrix is dominated by elastic fibers
Found in the ears, at the end of the nose, and in the epiglottis

25. Fibrocartilage Matrix is dominated by Collagenous fibers
A component of certain joints (intervertebral discs)

26. Bone
Matrix consists of mineral salts and collagen, which is maintain by osteocytes.

27. Types of Bone Compact Bone Spongy Bone
dense matrix filled with mineral salts and collagen arranged in concentric layers called lamellae
Osteonic canal located down the center, serves as a passageway for blood vessels
Spongy Bone
matrix consists of small plates of mineral salts and collagen called spicules that form a network with spaces in between
- spaces are filled with blood forming tissue called red bone marrow

28. Blood-Forming Tissue 2 Types: Manufactures blood cells
Contains stem cells, newly formed blood cells and protein
2 Types:
Red bone marrow- found in spongy bone; initiates production of all blood cells
Lymphoid tissue- found in lymph nodes, tonsils, spleen, and thymus; produces monocytes and lymphocytes

29. Membranes
Simplest combination of tissues in the body that forms a functional unit
Membranes divide areas of the body or organs, line hollow organs and cavities, and anchor organs

30. Mucous Membrane
Lines internal walls of the digestive, reproductive and respiratory tracts
Epithelium secretes mucus, which traps foreign particles, maintains a moist environment, and forms a protective layer over cells

31. Serous Membrane
Lines the internal surfaces of the thoracic and abdominal pelvic cavities
The epithelium secretes a watery fluid for lubrication

32. Cutaneous Membrane Also known as the skin
Makes up the primary organ of the integumentary system

33. Synovial Membrane
Lines inside walls of cavities that surround certain joints
No epithelial layer
Secretes a synovial fluid which lubricates the joints and nourishes joint cartilage

34. Muscle Tissue Consists of specialized cells to shorten or contract
Produce movement of body parts
2 Main Proteins in the cytoplasm of the cells:
1. Myosin
2. Actin

35. Skeletal Muscle
Attached to bones by bands of dense connective tissue called tendons
Voluntary control
Contains striations
Provides body movement

36. Cardiac Muscle Forms the walls of the heart Involuntary control
Contains striations
Propels blood through the body’s system of vessels

37. Smooth Muscle
Forms part of the walls of blood vessels and visceral organs
Involuntary control
No striations
Propels material as it passes through body tubes
Alters the sizes of organs

38. Nerve Tissue
Characterized by the well-developed properties of conductivity and excitability
Neurons- conduct electrochemical signals very rapidly
Neuroglia- support and maintain the neurons

39. Tissue Injury, Repair, Aging
Refer to page in the textbook.