HUMAN ANATOMY

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The Excretory System

• Learning Targets I can
• Name the 4 organs of the excretory system along
  with their function
• Identify the types of wastes removed by the
  organs
• Explain how the human excretory system is similar
  to a one celled organism.
• List and explain the homeostasis disorders
  associated with the excretory system

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Keeping an animal alive

• Had to evolve organ systems for
• getting materials in around
• digestive system
• respiratory system
• circulatory system
• removing wastes
• respiratory system
• excretory system

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Excretory System

• A. Purpose
• Excretion is the elimination of metabolic wastes
  from the cells.
• B. Why?
• To maintain homeostasis by regulating the water
  content of the blood, maintaining blood pH,
  removing waste products from the blood

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• C. How?
• Using the excretory organs
• (skin, lungs, liver, kidneys)

• D. Organs of Excretion
• How is the human excretory system similar to a
  one celled organisms?
• Like the cell membrane
• 2. Wastes CO2 diffuse out of
• cells
• 3. Contractile vacuole
• uses ATP to force water out
• against the gradient Transport Videos
• https//www.brainpop.com/health/bodysystems/urinar
  ysystem/

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1. Kidney-

• Major organ of the urinary system
• RENAL Refers to kidneys
• A. FUNCTION Filtering System
• Filter (clean) the blood using nephrons
• Makes urine (made of water, salts and urea)

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B. Kidney Structure
Write this down in the lower corner of your notes

• Renal Artery
• Carries unfiltered (dirty) blood from heart TO
  kidneys
• Renal Vein
• Carries filtered (clean) blood from kidneys TO
  heart
• Renal Cortex
• Outer portion
• Renal Medulla
• Corn shaped inner portion
• Nephrons
• Functional unit of the kidneys!
• Lie between cortex and medulla
• Millions of them!

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Structure of the Kidneys
Section 38-3
Kidney
Nephron
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Other

• a) Ureters
• Tubes that carry urine to bladder from kidneys
• b) Urinary Bladder
• Collects urine for excretion
• c) Urethra
• Transports urine out of body from bladder

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2. Liver

• Function
• Recycling of red blood cells, production of urea
• Urea is made from the breakdown of proteins
  (amino acids)
• Detoxification- Chemical poisons made harmless
• Glycogen- Stores excess glucose as glycogen and
  releases it as needed
• Bile Helps in the digestion absorption of
  fats
• Waste Urea
• Urea blood kidneys
  nephrons urine

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• FYI -The kind of nitrogenous waste you make
  depends on where you live

• Freshwater - ammonia
• Land- urea
• Egg layer - uric acid

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3. Skin

• Function
• largest gland
• regulates body temperature through perspiration
• Removes toxins
• Acts as a barrier for protection
• Waste Removed
• Water and salts (sweat)

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4. Lungs

• Also part of the respiratory system
• Wastes removed
• Rids body of CO2

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E. Excretory Homeostasis Disorders

• A. Kidney Stones
• 1. Calcium buildup in kidneys due to improper
  diet or unknown origin
• 2. Painful when in ureter
• 3. May need surgery if stone is too large
• B. Cirrhosis
• 1. Occurs when too much alcohols is consumed
• 2. Liver needs to work extra hard to metabolize
  alcohol
• 3. By products of alcohol (fats) accumulate in
  liver which causes scarring
• 4. Liver may shut down and homeostasis can no
  longer be maintained.
• C. Gout
• 1.Caused by deposits of uric acid in joints.
• 2.Common with high protein diets.
• 3.Suffer from stiffness and pain in joints.

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 Kidney Dialysis
Filters (cleans) blood because the kidneys cannot
Blood in tubing flows through dialysis fluid
Blood pump
Vein
Artery
Used dialysis fluid
Shunt
Air detector
Fresh dialysis fluid
Dialysis machine
Compressed air