1. Water and Electrolyte Balance in Animals
Terrestrial animals like this cheetah lose water every time they breathe and urinate! Drinking is an important way to gain water and maintain homeostasis! Chemical reactions of life happen inside of water! Humans can survive for weeks without eating, but only for 3 days without water. Water balance is achieved when water intake = water loss

2. Review: Types of Transport
Diffusion = movement of substances from high concentration to low cocnentration

3. Review: Types of Transport
Diffusion = movement of substances from high concentration to low cocnentration

4. Review: Types of Solution
Diffusion = movement of substances from high concentration to low cocnentration

5. Osmoregulation Osmoconformers =
Osmostic stress = when the concentration of dissolved substances in a cell or tissue is abnormal; osmoregulation is the process by which living organisms control the concentration of salt and water in their bodies; tissues are isotonic with respect to seawater

6. Osmotic Stress in Seawater Hypertonic environment
Osmoregulators =
Hypertonic environment
Osmoregulators = fish that actively regulate osmolarity;hypotonic relative to environment; water flows out of gills by osmosis  drink large quantities of seawater; drinking large amounts of water throws off electrolyte balance; have to actively pump out excess ions

7. Osmotic Stress in Freshwater Hypotonic environment

8. Osmotic Stress in Freshwater: Salmon
Chloride Cells have membrane proteins that can “flip”

9. Osmotic Stress on Land: Insects

10. Osmotic Stress on Land: Insects
Ability to close spiracles; spiracles located on underside of abdomen; waxy cuticle outer layer of exoskeleton

11. Types of Nitrogenous Wastes
NH3 (ammonia)
NH4+ (ammonium ion)
TOXIC!

12. Ammonia
Urea
Uric Acid
Image
Solubility
Toxicity
Water Loss
Energy Loss
Organisms
NH3 (ammonia)

13. The Master of Osmoregulation:
The Vertebrate Kidney
Cortex; medulla; most of kidney’s mass is made up of small structures called nephrons  over 1 million nephrons in each kidney!

14. A nephron; bowman’s capsule and glomerulus (ball of yarn) form a structure called the renal corpuscle

15. Renal Corpuscle: Filtration by Size
Water and small solutes (electrolytes) pass through pores; proteins, blood cells and other large components of blood do not. Blood pressure supplies the force for filtration; strains large volumes of blood without any ATP needed; form a filtrate  about 25% of water and solutes present in blood is removed  capable of producing 180 liters of filtrate per day; about 99% is recycled

16. Reabsorption: The Proximal Tubule Active Transport via Protein Pumps

17. Reabsorption: The Loop of Henle Creating an Osmotic Gradient

18. Predict what happens to the osmotic gradient when the drug flurosemide inhibits membrane proteins that pump sodium and chloride ions out of the thick ascending limb.

19. Tight Control via Hormones
The Collecting Duct:
Tight Control via Hormones
ADH =

20. What impact will this have on an individual?
Alcohol inhibits AHD 
What impact will this have on an individual?
Nicotine stimulates ADH release What impact will this have on individual?

21. What impact will this have on an individual?
Alcohol inhibits AHD 
What impact will this have on an individual?
Nicotine stimulates ADH release What impact will this have on individual?

22. Tight Control via Hormones
The Collecting Duct:
Tight Control via Hormones
Aldosterone =
Low blood volume: Sodium re-absorption increases, water follows; blood volume restored