1. HISTOLOGY THE STUDY OF TISSUES

2. TISSUES Organization of similar cells embedded in a matrix (nonliving, intercellular material Matrix can be rigid, gel, fluid or nonexistent Specialize in performing at least one unique function essential for life

3. 1. EPITHELIAL Covers and protects body surface Lines body cavities Secretes and absorbs substances into and out of blood Forms glands

4. 2. CONNECTIVE Supports and connects body and its parts Transports substances throughout the body Protection from invading microbes Cells spread out; lots of matrix

5. 3. MUSCLE Produces movement by shortening complex contractile proteins

6. 4. NERVOUS Communication between body parts and integration of their activities

7. 1. EPITHELIAL 2 types: 1. Membranous – covers and lines body 2. Glandular – exocrine and endocrine

8. FUNCTIONS Protection Secretion Absorption Excretion Sensory

9. CHARACTERISTICS Limited amount of matrix Basement membrane Avascular Held together by fused cell membranes Reproduce by mitosis Nutrients by diffusion Polarity

10. CLASSIFICATION OF MEMBRANOUS EPITHELIUM Based upon cell shape –Squamous (flat), cuboidal, or columnar Based upon # of cell layers –Simple (single) or stratified (layered)

12. Simple squamous

16. Simple cuboidal

20. Simple columnar

23. Pseudostratified

26. Transitional

28. Nonkeratinized stratified squamous

34. CLASSIFICATION OF GLANDULAR EPITHELIUM Exocrine – discharge products into ducts 1. Apocrine 2. Holocrine 3. Merocrine Endocrine – ductless glands

37. II. CONNECTIVE Most abundant and diverse Connects, supports, transports and defends Few cells, mostly matrix (nonliving extracellular material); various numbers and kinds of fibers

41. 1. AREOLAR Most common and widely distributed Matrix is soft gel – hyaluronic acid Matrix = collagen and elastin fibers Fibroblasts (secrete matrix) are the predominant cells Macrophages (phagocytosis) Mast cells – secrete histamine

42. Areolar

44. B. ADIPOSE Mostly fat cells (adipocytes) Protection, insulation, energy storage

45. Adipose

47. C. RETICULAR 3-D web Defense; reticular network filters harmful substances from lymph and blood Reticular cells phagocytic

48. Reticular

50. D. DENSE REGULAR Mainly bundles of collagen arranged in parallel rows Few fibroblasts Ligaments (bone to bone) and tendons (muscle to bone)

51. Dense regular

52. E. DENSE IRREGULAR Dermis of the skin Joint capsules

53. Dense irregular

54. 6. CARTILAGE One cell type: chondrocyte Chondrocytes produce fibers and tough gristlike material (chondroitin sulfate) Avascular – nutrients diffuse through perichondrium which surrounds cartilage mass

55. F. HYALINE CARTILAGE Shiny Most prevalent type Support tubes of respiratory system, ribs, tip of nose, ends of long bones that articulate at joints

56. Hyaline cartilage

58. G. ELASTIC Strong and flexible External ear, epiglottis

59. Elastic cartilage

61. H. FIBROCARTILAGE Strongest Shock absorbers Found between vertebrae and knee joints Rigid matrix filled with strong white fibers

62. Fibrocartilage

64. I. BONE Osteocytes in matrix of collagen and mineral salts (65%) Support, protection, muscle attachment; mineral storage; hemopoiesis Haversian system

65. Bone

68. J. BLOOD Liquid matrix Fibers only present at clotting Plasma = 55% Erythrocytes, leukocytes and platelets are the cells

69. Blood

71. III. MUSCLE A. Skeletal –Multinucleate, cross striations B. Cardiac –Heart wall; cross striations, intercalated disks, involuntary Visceral C. Smooth –involuntary, one nucleus per cell, non striated

72. Skeletal muscle

74. Cardiac muscle

76. Smooth muscle

78. IV. NERVOUS Nerve cells –Neurons Cell body (soma), axons (away) dendrites (toward cell body) Neuroglia –Connecting and supporting cells

79. IV. Nerve