Kidney and its Role in Maintaining Homeostasis

Do fish pee?

• Which fish has to drink?• Which fish has more dilute urine?

Do birds pee?

Investment of energy in producing nitrogeneous waste!

Fish--little investment--Ammonia

Mammals--some investment for storage in bladder--Urea

Birds--produce uric acid which can be stored as solid waste!!

Role of the Excretory System

• Filtration:

• Rebsorption:

• Secretion:

• Excretion:

Organization of Excretory System

Functional Unit: Nephron Organization

Functional Unit: Nephron Organization

Why are you thirsty?• Blood osmolarity is greater

than the set point!• The extra solute in your

blood interacts with receptors in your brain.

• The hormone ADH (Anti-diuretic hormone) works to correct this!

Does caffiene make you pee more?

• Caffiene is a weak inhibitor of ADH.

• What would that do?

• Does coffee/Coca-Cola quench your thirst?

What if your kidneys stop working?

• Hemodialysis

What are kidney stones?

• Buildup of vitamins or minerals.

• Due to diet/genetics

Can you die from drinking too much (water)?

• Yes!• Hyponatremia • What is out of balance?• What organs are affected

Review

• Find an online kidney animation:

• As you are watching the animation, highlight key information from your notes.

• At the end of your notes, identify two new pieces of information you learned!