1. Aquatic Physiology Respiration gill diffusion hemoglobin pH Regulation gas bladder osmosis ion balance excretion Chapter 3: Figures 3.1, 3.2, 3.3, Table 3.1 Chapter 4: Figures 4.4, 4.5, 4.6 (Eq.) Chapter 5: Figures 5.1, 5.2, 5.3 (5th ed.) Chapter 6: Figures 6.1, 6.2, 6.4, 6.6

2. Week 7: Aquatic Regulation buoyancy

3. elasmobranchs and coelacanths lipid/oil-filled liver 1/3 of body wt 90% oil ~ food reserve ~ buoyancy at any depth, P also cartilage rigid fins for lift

4. South American lungfish Australian lungfish African bichir Asian climbing perch North American gar physoclistous physostomous osteichthyans: air/gas bladder Figure 5.1, 5 th ed. only. gas bladder ~ air/gas reserve ~ buoyancy declines w/depth, P

5. PV = nRT (ideal gas law) pressure x volume = # gas molecules x constant x temperature aquatic environment: 10 m decrease in depth ~ 1 atm increase in pressure gas bladder: neutral buoyancy ½ @ 10 m 1/3 @ 20 m pressurevolume 1/4 @ 30 m P ~ 1/V sink...

6. pikeperch physostomous (open to gut/ mouth) physoclistous (closed to gut/mouth) Gas Bladder: 2 types surface to 100 m > 100 m depths

7. rete (mirabile) gas gland physostomous (open to gut/ mouth) physoclistous (closed to gut/mouth) 25x rete length ~ 10x max. depth

8. gas bladder gas gland and rete system deepsea snaggletooth Astronesthes to 200 m rete mirabile =“wonderful net”

9. rete (mirabile) gas gland Figure 5.2 [5.1]Figure 5.3 [5.2 4 th and 3 rd Eds.] high pressuregas diffusion

10. very high pressure 2. salting out (HCO 3 - ) decrease in blood volume (V) and increases pressure (P) 1. Root effect (H + ) increases O 2 (n) and increases pressure (P) PV = nRT rete (mirabile) bicarbonate equillibrium

11. glucose: a. lactate (salting out) b. hydrogen (Root effect) c. carbon dioxide (inflation) surfactant increases surface wall tension to prevent pressure collapses (see in lungs) Gas bladder otherwise impermeable expandable gas gland pressure:very highless highlower

12. Aquatic Physiology Respiration gill diffusion hemoglobin pH Regulation gas bladder osmosis ion balance excretion Chapter 3: Figures 3.1, 3.2, 3.3, Table 3.1 Chapter 4: Figures 4.4, 4.5, 4.6 (Eq.) Chapter 5: Figures 5.1, 5.2, 5.3 (5th ed.) Chapter 6: Figures 6.1, 6.2, 6.4, 6.6

13. Week 7: Aquatic Regulation osmoregulation

14. osmosis diffusion across a semi-permeable membrane pressure builds regulation... high to low (dilution) impermeable to solutes = ions/salts: Na + Cl - H + HCO 3 - NH 4 + NH 3 permeable to water

15. freshwater (+) (+ + +) gain water hyper-osmotic [more] fw fish fish 3x > freshwater environment

16. seawater (+ + +) (+) lose water fish : sw fish 3x < saltwater environment hypo-osmotic [less]

17. osmoregulatory structures 1. gill 2. kidney

18. Figure 6.1 osmoregulation 1. gill 2. kidney

19. more simplified...

20. freshwater (+) (+ + +) 1. gains water osmosis 2. loses water (dilute urine) kidney production 3. loses salts 4. salts in gill active transport/exchange hyper-osmotic

21. saltwater (+ + +) (+) osmosis 2. drinks water 3. gains salts 4. salts out gill ATP active transport 1. lose water some divalent salts Ca 2+, Mg 2+ out in urine no well-developed kidney hypo-osmotic

22. urea, salts elasmobranchs and coelacanths retain urea [saltwater] (+ + +) saltwater (+ + +) iso-osmotic = equal

23. OsteichthyesChondrichthyesBirds Nitrogen waste: produced stored

24. nitrogen pathways sizesmallerlarger solubilityhigherlower organ for excretiongillkidney expenselowerhigh toxicityhigherlower water requiredyesno total N/molecule 12 use in regulation ion exchangeiso-osmosis

25. elasmobranchs and coelacanths (+ + +) saltwater (+ + +) iso-osmotic = equal 1. gains salts in food 2. salts out via rectal gland

26. Figure 6.1 osmoregulation 1. gill 2. kidney

27. base of lamellae main osmoregulatory structure chloride cells

28. Figure 6.2 SW chloride cell (alpha) ~ “rectal gland” move salts out against a concentration gradient

29. Figure 6.4 FW chloride cell (beta) move salts in against a concentration gradient

30. diadromy ~3 days chloride cells salt transport kidney urine function behavior

31. Week 7: Aquatic Regulation excretion

32. osmoregulatory structures 1. gill 2. kidney excretion: carbon dioxide nitrogen hydrogen

33. Figure 6.6 5 th Ed. = NH 3 gill

34. gill excretion: carbon dioxide

35. gill excretion: nitrogen NH 3 + H + = NH 4 + ammonia ammonium ion

36. nitrogen pathways sizesmallerlarger solubilityhigherlower organ for excretiongill ~ NH 4 + kidney expenselowerhigh toxicityhigherlower water requiredyesno total N/molecule 12 use in regulation ion exchangeiso-osmosis

37. gill excretion: nitrogen Na + for NH 4 + sodium for ammonium same electrochemical (+) charge

38. gill excretion: hydrogen 1. sodium for hydrogen same (+) charge 3 pathways: 2. 3.

39. freshwater (+) (+ + +) 1. gains water osmosis 2. loses water (dilute urine) kidney production 3. loses salts 4. salts in via NH 4 + and H + exchange for Na + gill active transport/exchange hyper-osmotic

40. chloride for bicarbonate ion same (-) charge electrochemical gradients (+ and -)

41. osmoregulatory structures 1. gill 2. kidney excretion: water salts conservation: water salts

42. tetrapods fishes kidney nephron capsule = filter (salts) loop = reabsorb water: constriction salts: wave

43. organ nephron unit (100s to 1000s)

44. nephron capsule: loop: ammonia urea water salts enzymes

45. tetrapods fishes kidney nephron capsule = filter (salts) loop = reabsorb water: constriction salts: wave no constriction to concentrate urine