1. Histology 14 with supplement Much of this is from Histology 14 Liver Respiration

3. Pig liver (20X)

4. Human (20X)

5. Alternative theory to hepatic systems –Lobule Classical Portal –Acinar (grape-like)

8. PV – portal venule A – hepatic artery L – lymphatic duct B – bile duct S – sinusoids Limiting plate

9. Respiratory System Main functions: –Conducts air in/out –Exchange gasses w/blood – respiration –Includes mechanisms to prevent collapse of conducting tubes Bones Cartilage –Two major tube types: 1.Conducting pathway (nasal portion – lungs) 2.Respiration pathway (area of alveolar sacs)

10. Conducting Pathway Specialized lining of epithelium –“respiratory” epithelium that changes with arborization –Pseudostratified ciliated columnar epithelium With goblet cells – secrete lots of mucus –Cilia beat in one direction: Above pharynx – beat downwards Below pharynx – beat upwards Mucocilary escalator Mucus moved throughout passageway – trap dust

11. Conducting Pathway (cont.) Blood vessels – warm and moisten air Trachea (main passageway): –Contains C-shaped rings in adventitia R,L primary bronchi (enter lungs) –Same as trachea –Cartilage becomes reduced in bronchi of lungs –Epithelium – begin with pseudostrat ciliated to ciliated columnar Bronchioles –Epithelium – ciliated cuboidal to non-ciliated simple squamous Terminal bronchioles Respiratory bronchioles – start of the respiratory pathway Decrease in cartilage, glands, goblet cells height of epithelium Increase in smooth muscle and elastic tissue Extrapulmonary- Intrapulmonary-

12. Cells Type I pneumocytes –95% of alveolar surface –Highly flattened –Simple squamous epithelium –Form occluding junctions with one another Barrier to extracellular fluid into alveolus Type II pneumocytes –More numerous; only about 5% of alveolar surface –Cuboidal –Dispersed among type I pneumocytes and form occluding junctions with them –Job: provide surfactant – glycoprotein; reduces surface tension (alveolus won’t collapse) Dust Cell –Small macrophages –Can pass over gas-blood barrier of alveoli

15. Trachea xs

16. Trachea ls E – epithelium LP – lamina propria SM – submucosa F – fibroelastic tissue

17. Primary bronchus E – epithelium LP – lamina propria M – smooth muscle G – seromucous glands C – cartilage Goblet Cells in epith.

18. Bronchiole V – vein M – sm. Muscle

19. Terminal portion of respiratory tree –T – terminal bronchiole –R – respiratory bronchiole –V – pulmonary vessel –AD – alveolar duct –AS – alveolar sac –A - alveolus

20. Drawings of gas exchange

21. Capillaries Lumen of capillary Endothelial cell Lumen of alveolus Pneumocytes