The%20Excretory%20System

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The Excretory System
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Excretion

• The process by which wastes and excess
  substances are removed from an organism
• Organs of excretion are
• Lungs
• Kidneys
• Liver
• Skin

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Liver

• Liver removes harmful substances from the blood
  such as bacteria, certain drugs, and hormones
• The liver breaks down excess amino acids to form
  urea
• Too much alcohol can lead to cirrhosis of the
  liver
• Bile is considered an excretory product of the
  liver

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A healthy liver and the liver of a person with
cirrhosis
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The Urinary System

• The urinary system is included in the excretory
  system.
• Kidneys filter urea from the blood to make
  urine
• Ureter tube through which urine passes from
  each kidney to the urinary bladder
• Urinary Bladder where urine is stored
• Urethra the tube that carries urine from the
  bladder to the outside of the body

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Kidneys

• Organs of the excretory system that act like
  filters.
• The two kidneys are located near the spine in the
  middle of the back.
• They are protected by lower ribs and covered by
  layers of fat.
• Without the kidneys, it would not take long
  before the bodys system would be poisoned.
• It is possible to function with only one kidney.

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Urine

• Waste drains out of the kidneys in the form of
  urine.
• Urine is about 95 water and 5 urea (protein
  from protein breakdown).
• Fresh urine has no bacteria in it.

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Lungs

• An organ of the excretory system that rids the
  body of carbon dioxide and water (water vapor).

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Skin

• An organ in the excretory system which removes
  excess heat.
• When the body becomes too warm, extra heat is
  lost
• Evaporation of sweat removes heat and cools the
  body

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• The skin is the largest organ in the body
• It contains sweat glands through which sweat is
  released
• Sweat is made up of
• 98 water
• 2 salt
• Small amounts of urea

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Excretory Disorders

• Kidney stones - result when urine becomes too
  concentrated and substances in the urine
  crystallize to form stones

Risk factors -Family or personal history -Being
an adult (40) -Being a man -Dehydration -Diets
high in protein, sodium, and sugar -Obesity -Diges
tive diseases and surgery -Other medical
conditions
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Excretory Disorders

• Renal Failure results when the kidneys fail to
  function correctly which leads to abnormal levels
  of fluids in the body

Kidney dialysis averages 4 hours per session, 3
times per week.
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Ways to Protect Your Kidneys

• Eat a diet low in fat and salt
• Exercise most days of the week
• Drink water (8 glasses/day)
• Avoid tobacco
• Limit alcohol