Liquid Excretion: removal of liquid wastes

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Liquid Excretion removal of liquid wastes
water/salt balance

• Ch 37.3
• The Urinary System

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Nitrogen wastes are excreted cycled
Nitrogen in Plant animal protein
Ammonia nitrogen Is excreted in urine
Bacteria convert Ammonia to usable Nitrate
fertilizer
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Forms of Nitrogen Wastes
Nitrogen form Toxicity Environment removal
1. Ammonia Most Water by diffusion
2. Urea Less Land _at_ kidney as urine
3. Uric Acid crystal Least Air Deserts as A dry crystal
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Protein Building blocks
H-N H

• R.Gr.

COH H
Acid COOH
Amino NH2
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Nitrogen waste from Protein Breakdown

• Kidney filters the blood
• Removes urea waste
• Recycles food, water salt
• Urine urea waste, water salt

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Bladder stores Urine made by Kidneys
Ureter tubes Carries urine to urethra
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Nephron Unit of filtration
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Water levels in urine under control of
Hypothalamus ADH hormone
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Kidney Transplants