3. Basic Gill Anatomy Lamella Filament (2 rows) Gill Raker Gill Arch 4/side

4. Arch Filament Lamellae

7. Water flow through gills, ventral view Bony Fish Water

8. What about sharks?

9. Water flow through gills, ventral view Bony Fish Shark Water

10. What about lampreys?

12. Lamprey Gills Gill Sack Gill Hole Mouth Pharynx Intestine

13. Micro Gill Anatomy

16. Gill Anatomy Lamella Afferent Artery Efferent Artery Afferent Artery Cartilage Rod Efferent Artery Water Flow

17. Gill Cross Section Afferent Artery Filament Lamella Efferent Artery Cartilage Arch Water Flow

18. Countercurrent Exchange

19. Parallel vs. Counter-current 0 100 50 100 20 80 0 0 4060100 804020 0 10075 25 60 4046 54 50 Counter-current Parallel

20. Gill Anatomy Lamella Afferent Artery Efferent Artery Afferent Artery Cartilage Rod Efferent Artery Water Flow

21. Lamella Cross Section Peripheral Channel Basement Membrane Pillar Cell Epithelial Cell Red Blood Cell

23. Filament Cross Section Central Sinus C AE Pillar Cell Afferent Artery Cartilage Lamella Efferent Artery

25. Ammonia Ammonia

26. Infection Infection

29. Iron Iron

30. Parasites Costia Parasites Costia

31. Parasites “Hamburger gill” Parasites “Hamburger gill”

33. Hemoglobin in High and Low Oxygen Hb High Oxygen Low Oxygen Hb 43

36. Niels Bohr 1885-1962 Christian Bohr 1855-1911

37. CO 2 + H 2 0H 2 CO 3 Carbonic Acid Low CO 2 High pH High CO 2 Low pH Bohr Effect

38. CO 2 + H 2 0H 2 CO 3 Carbonic Acid Low CO 2 High pH High CO 2 Low pH Bohr Effect

39. Tissues have a lower pH than the gills At lower pH, oxygen does not bind as strongly to Hb (lower affinity) Therefore, oxygen falls off even faster Hb O OO O

40. Hemoglobin in High and Low Oxygen/pH Hb High Oxygen & pH Low Oxygen & pH Hb 423

42. Oxygen dumped from Hb into tissues because… Oxygen concentration in tissues is lower so when oxygen falls off Hb it takes a long time to be replaced The Bohr effect in tissues makes oxygen fall of easier there than it does in the gills The net effect is that each Hb in the gills is usually bound to 4 oxygen molecules while Hb in the tissues is bound to only 2 This, 2 oxygen molecules are dropped off by each Hb

43. Quizzzzz Basic gill anatomy; label the parts Pillar cells and thin epithelium are critical! Countercurrent exchange How hemoglobin works –Oxygens drop off at low concentration –Bohr