1. Introduction to Human Tissues #3 Laura Fraser Cotlin, Ph.D. Fundamentals 2 – Dental/Optometry November 2, 2011

2. Classification of Connective Tissues Embryonic connective tissues 1. Mesenchymal 2. Mucous Connective tissue proper 1. Loose (areolar) 2. Dense a. Dense irregular b. Dense regular -collagenous -elastic Specialized connective tissue 1. Cartilage 2. Bone 3. Blood 4. Adipose

4. - involved in energy storage, insulation, cushioning of organs and secretion of hormones -Large cells, can be up to ~100um -Lipid mass is not membrane bound -White (unilocular) or brown (multilocular) Hormones involved in short-term weight control ghrelin – stimulates appetite Peptide YY – induces sense of fullness Hormones involved in long-term weight control leptin – produced exclusively by adipocytes. -generally thought to reduce appetite (obese people have high levels and are thought to be resistant to leptin action) insulin – enhances conversion of glucose into triglycerides

5. Fat absorption and release

8. The hematocrit of human blood -volume of cells and plasma is ~45 and 55% respectively -Hematocrit - volume of packed erythrocytes in a sample of blood Normal hematocrit ~39-50% in males ~35-45% in females Leukocytes and platelets constitute only ~1% of blood volume

11. CARTILAGE Specialized connective tissue, part of skeletal system Functions: provide flexible support (bone rigid template for bone formation Locations: limited sites – respiratory system, joints, external ear Composition: cells + matrix (properties from matrix) 1. Matrix: a. Fibers: collagen II, elastic fibers b. Ground substance: proteoglycans and glycosaminoglycans (GAGs) 2. Cells: chondroblasts, chondrocytes, c b d c a

12. FEATURES OF CARTILAGE CARTILAGE IS A SHOCK ABSORBER Add pressure: water forced out of tissue, absorbs pressure Release pressure: water rebinds PG aggregate and tissue returns to original size Avascular No nerves No lymphatics Perichondrium Isogenous group Chondrocyte in lacuna Territorial matrix around chondrocytes Interterritorial matrix between isogenous groups or single cells.

14. TYPES OF CARTILAGE 1.Hyaline: most common – nasal septum, joint surface, ribs 2.Elastic: enriched with elastic fibers – ear, larynx - Looks like hyaline cartilage with the addition of elastic fibers between cells 3.Fibrocartilage: found in interverterbral disks, tendon/ligament attachment. -See rows of chondrocytes with increased fibrous matrix between between them

15. Hyaline Cartilage

16. Elastic Cartilage

18. Fibrocartilage

20. FUNCTIONS OF BONE 1.Support 2.Protection (skull) 3.Locomotion 4.Calcium store (also Mg and Na) 5.Hematopoiesis (marrow) TYPES OF MATURE BONE Cancellous (spongy): fine irregular plates – trabeculae inside long bones (marrow) gives strength without weight Compact: highly ordered Types: outer and inner circumferential lamellae -contains Haversian systems (osteons)

21. COMPOSITION OF BONE: cells + matrix Matrix 1.Organic a) fibers: type I collagen, highly organized b) ground substance: little, some PG as cartilage 2.Inorganic: Calcium phosphate complexes forms 50% of the matrix, giving the material its rigidity ***Bone looks solid but is alive, dynamic and continually remodeling. ***Is highly vascularized (compared to cartilage)

22. PRIMARY CELLS IN BONE 1.Osteoblasts: immature, synthesize and secrete osteoid, which becomes mineralized to give bone; do not divide. 2.Osteocytes: surrounded by matrix, maintain matrix; do not divide. 3.Osteoclasts: large multinucleate cells, resemble macrophage in function, remodel bone by resorbing bone matrix.

23. Main cells include: -Osteoblast -Osteocyte -Osteoclast

24. EPIPHYSIS DIAPHYSIS EPIPHYSIS Articular cartilage Cancellous bone Compact bone Periosteum Marrow cavity

25. Compact (Ground) Bone

27. Muscle Tissue

31. Structure of Skeletal Muscle Tissue

33. EM of Striated Muscle

34. The Sarcomere –extends from Z-line to Z-line -the smallest repetitive subunit of the contractile unit

35. Arrangement of Thick and Thin Filaments

36. Sarcomeres at different functional stages

37. Neuromuscular Junction

38. Cardiac Muscle Tissue

43. Smooth Muscle Tissue

46. Nerve Tissue

47. ORGANIZATION OF NERVOUS SYSTEM

48. Can be divided into: -the somatic nervous system -the autonomic nervous system -sympathetic division -parasympatheic division -enteric division Components include: -cranial nerves -spinal nerves -peripheral nerves -ganglia -somatic or sensory - dorsal root ganglia -autonomic sympathetic, parasympathetic, enteric -specialized nerve endings Peripheral Nervous System

49. Types of Neurons Can be classified based on: -morphology -function -neurotransmitters

50. Organization of a Typical Neuron

51. From Junqueira and Carneiro. McGraw-Hill Publishing, 2005 Nerve Organization

52. From Junqueira and Carneiro. McGraw-Hill Publishing, 2005