1. Chapter 5 Tissues

2. Intercellular Connections Individual cells connect to form tissues 3 ways: –Tight junctions- –Desmosome- adhesion between cells in spots. Allows from some permeability. –Gap junctions- cytoplasms of adjacent cells are connected through transport proteins. Ions can pass freely through cells.

3. Intercellular Connections

4. Tissue Types A tissue is a group of cells with a common structure & function The human body is composed of four main tissue types: 1. 2. Connective 3. 4. Nerve

5. Epithelial Tissue

6. Characteristics Always has a free (apical) surface exposed to outside or open space. Has a basement membrane to anchor underlying tissue

7. Functions Covers body surfaces Protects Absorbs Excretes

8. Classified by Shape Squamous – Cuboidal – Columnar –

9. Classified by Shape May occur in layers: Simple – Stratified – 2 or more layers Pseudostratified – Example – simple cuboidal Example – stratified columnar

10. Examples of Epithelial Tissue

11. s Simple Squamous- Thin, flattened cells. Allow for diffusion and filtration. Line air sacs of lungs and walls of capillaries.

12. Simple cuboidal- single layer of cube shaped cells. Lines follicles of thyroid gland, kidneys and ducts of certain glands.

13. Simple columnar- single layer of elongated cells. Can contain cilia, used for protection and absorption in digestive tract.

14. Stratified squamous- Layers of squamous cells. Make up epidermis and line cavities exposed to external environment.

15. Stratified columnar- Several layers of columnar cells overlying cuboidal cells near the basement membrane.

16. Pseudostratified ciliated columnar- Appear stratified but are not. Often contain cilia and goblet cells which secrete mucus.

17. Pseudostratified ciliated columnar w/goblet cells- Line Respiratory passages to trap unwanted particles

18. Transitional tissue- Changes in response to change in tension. Line urinary bladder and urethra.

19. Glandular Epithelium Specialized to secrete substances Those that secrete substances into ducts that open onto a surface are Those that secrete into tissues or blood are

20. Classifying Glands by Structure Simple- Compound- duct that does branch before secretory portion.

21. Classifying Glands by Type of Secretions 3 types: Small portions of cells in secretions No loss of cytoplasm Ex. – mammary glands in secretions Ex. – pancreas

22. Classifying by Secretions Secretions w/entire cells filled w/secretory products; ex. – sebaceous (oil) glands

23. Connective Tissue

24. Functions 1.connects 2. 3. protects 4. 5.fills spaces

25. Functions 6. stores fat 7. 8. protects against infection 9. 10.helps repair damaged tissue

26. Characteristics 1. Consists of cells in a matrix (intercellular material) 2. Cells some distance apart 3. 4.

27. Types of Fibers: 1. collagenous – composed of collagen (protein); have great tensile strength; slightly elastic; compose bones, tendons & ligaments

28. Types of Fibers - continued elastic – composed of elastin (protein); very elastic but weaker; compose vocal cords & air passages of lungs

29. Types of Fibers - continued Reticular – composed of very fine collagenous fibers.

30. Types of Cells 1. Fixed cells – stay in one place & have stable numbers; 2 types: fibroblasts – large & star-shaped; most prevalent

31. Types of Cells - continued mast cells – may release heparin (for blood clotting) & histamines (promotes allergic reactions & inflammation); usually located near blood vessel walls

32. Types of Cells - continued 2. Wandering cells – macrophages – (Purple cells – macrophages, Green cells – T-lymphocytes)

33. Examples of Connective Tissue

34. Areolar tissue- binds the skin to underlying organs and under epithelium to provide bloodflow.

35. Adipose tissue- connective tissue composed of fats, cushion joints and provide insulation

36. Regular dense connective- strong fibers bind body parts together. Found in ligaments and tendons.

37. Irregular dense connective- disorganized and strong. Found in the dermis

38. Hyaline cartilage- Most common, found on ends of bones, nose cavity and supporting rings of resp. system.

39. Fibrocartilage- tough tissue containing collagenous fibers. Shock absorbers between vertebrae.

40. Elastic cartilage- flexible cartilage make up ears and larynx

41. Blood - platelets

42. Blood – red cells & white cell

43. Elastic connective

44. Reticular connective

45. Bone- A- central canal (contains blood vessels) B- Canaliculi- minute tubes allow for movement between cells.

46. Bone- D- Lamellae (layers of osetocytes), C- osteocytes

47. Muscle & Nerve Tissue

48. Muscle Tissue 3 types: Skeletal- Used for movement Smooth- lacks striations found in skeletal, used for involuntary movements Ex- move food through digestive tract Cardiac-

49. 3 Types of Muscle Tissue

50. Smooth muscle- B- nucleus

51. Skeletal muscle- A- striations, B- nucleus

52. Cardiac muscle

53. Nervous Tissue Found in the brain, spinal cord and peripheral nerves. Cells called neurons – Also include neuroglia cells (support cells) –Support the function of the neurons

54. Nerve tissue – A- neuron, B- Axon, C- neuroglia