Excretion

Is the processes in the body that removes metabolic wastes. Wastes such as

• excess water, H2O• Urea,• Carbon dioxide, CO2

• and other wastesfrom our blood.

Major Organs of Excretion

Skin

Excretes:• Sweat (water and salt)• dead skin cells• bacteria

Lungs

Excretes:• carbon dioxide (CO2)• water

Kidneys

Every drop of your blood is filtered by the kidneys 300 times per day. The kidneys excrete:

• waste from all cells• salts• fats• urea• water

Kidney NephronsKidney tubules (nephrons) are the Kidney’s functional units. They remove:

• Urea• Sodium• potassium• Water

from the blood and excrete them as urine.

Kidneys also play important roles in:• maintenance of blood volume• blood pH• red blood cell production.

There about a 1 million Nephrons in a Kidney.

Structure of a Nephron

Lesser organs of Excretion

Liver

This organ secretes bile and other chemicals to break down fats and other wastes in the blood.The liver filters out drugs.The waste goes to the kidneys to be taken to the bladder. The liver changes toxic ammonia, to harmless urea.The liver is the largest gland in the body.

Ureter

connect the kidneys to the bladder to transport waste from the kidneys to the bladder for storage.

Bladder

Bladder/ Urinary bladder- this is the storage place of the extra water and waste sent by the kidneys to be taken out the system by urination through the urethra

Urethra

Is the tube urine exits the bladder.

Large Intestine

The large intestine, or the colon, removes solid waste from the body.

The Colon collects water from the waste that can be reused.

It is about 6.5 meters long.

Kidney stone1. A kidney stone is material that forms in a kidney out of substances

in the urine.2. A stone may stay in the kidney or break loose and travel down the

urinary tract. A small stone may pass all the way out of the body without causing too much pain.

3. A larger stone may get stuck in a ureter, the bladder, or the urethra. A problem stone can block the flow of urine and cause great pain.

Causes of Kidney Stones

1. Decrease in urine volume2. Dehydration3. Medical conditions, such

as gout.4. Medications or supplements.5. Dietary and hereditary

factors are also related to stone formation.

Cures - Shock Waves

A machine is used to send shock waves directly to the kidney stone to break it up into smaller stones that will pass through your urinary system with your urine.

Cures - Tunnel Surgery

A small cut is made into the patient's back. A narrow tunnel through the skin to the stone inside the kidney.

With a special instrument that goes through the tunnel, the doctor can find the stone and remove it.

Cures - Ureteroscope

The doctor inserts the ureteroscope into the patient's urethra, passes it up through the bladder, and directs it to the ureter where the stone is located. The ureteroscope has a camera that allows the doctor to see the stone. A cage is used to catch the stone and pull it out, or the doctor may destroy it with a device inserted through the ureteroscope.

Appendicitis

Colostomy Stoma

Constipation

Diarrhea

Gallbladder

Hemaroids

Ulcerative Colitis / Celiacs

Normal bowel

Excretory Questions

1. List the 3 major organs of the Excretory system.2. What is the main organ of the Excretory system?3. What is the function of the main organ of the

Excretory system?4. Briefly describe the function of the nephron.5. What is the major cause of Kidney Stones?6. Describe one cure for Kidney Stones.7. When you eat greasy french fries your small

intestine absorbs the grease and other nutrients into your blood. Why doesn’t the grease clog up your young arteries?