Ch. 4 Part 3

1. Ch. 4 Part 3 Connective tissues

2. Connective Tissue • Most abundant and widely distributed tissues in the body • Functions: • Binds together, supports and strengthens other body tissues • Protects and insulates internal organs • Compartmentalizes structures such as skeletal muscles • Serves as major transport system within the body • Primary location of stored energy reserves • Main source of immune responses

3. Connective Tissue • Consists of 2 basic elements • Extracellular matrix • Material located between its widely spaced cells • Consists of protein fibers and ground substance • Usually determines characteristics (ex: bone – hard and inflexible) • Cells

4. Connective Tissue Cells • Vocab • Blast = to bud or sprout (immature cells) • Fibroblast, chondroblast, osteoblast • Cyte (mature cells) • Chondrocyte, osteocyte - “blast gives rise to cyte”

5. Connective Tissue Cells • Macrophages • Irregular shape with short branches • Where: wandering and fixed (lungs, spleen) • Function: engulf bacteria and cellular debris • Fibroblasts • Large, flat cells with branches • Where: several types of tissue • Function: migrate through C. T. secreting fibers

6. Connective Tissue Cells • Plasma cells • Small • Where: most places, especially gastrointestinal and respiratory tracts • Function: secrete antibodies for immune response • Mast cells • Where: alongside blood vessels • Function: produce histamine for inflammatory response; can bind to and kill bacteria

7. Connective Tissue Cells • Adipocytes • Also called fat or adipose cells • Where: deep to skin and around organs • Function: store triglycerides (fats) as energy • White blood cells • Not normally in C. T. but can migrate there in response to infection

8. Connective Tissue Cells

9. Checkpoint • In what ways do connective tissues differ from epithelia? • What are the features of the cells of connective tissue?

10. Extracellular Matrix • Two major components • Ground substance • Component of C. T. between cells and fibers • Fibers • Collagen fibers, elastic fibers, reticular fibers

11. Connective Tissue Types • Embryonic – we will not study • Mature – we will study • Loose • Areolar, adipose • Dense • Cartilage • Hyaline, fibrocartilage, elastic • Bone • Liquid • Blood

12. Mature Connective Tissue Types • Areolar C. T. • Contains: fibroblasts, macrophages, plasma cells, mast cells, adipocytes, white blood cells, collagen fibers, elastic fibers, and reticular fibers • Where: form subcutaneous layer – attaches skin to underlying tissues • Adipose • Single cells filled up with single, large triglyceride droplet • Cytoplasm and nucleus pushed aside • Found everywhere areolar is found • Requires blood flow – heavier = more blood vessels = high blood pressure

13. Areolar Adipose

14. Mature Connective Tissue Types • Cartilage • Collagen and elastic fibers in a gel-like substance • Can endure stress • Chondrocytes – mature cartilage cells; occur singly or in groups within lacunae • Has no blood supply – heals poorly after injury • 3 types – hyaline, fibrocartilage, and elastic

15. Cartilage

16. Mature Connective Tissue Types • Bone • Also called osseous tissue • Includes marrow, endosteum, periosteum • Basic unit of compact bone is osteon or Haversian system • Blood • Consists of: plasma, red blood cells, white blood cells, platelets

17. Bone Blood

18. Checkpoint • Describe the following: • Areolar connective tissue • Adipose tissue • Cartilage • Bone tissue • Blood tissue