Period1-Notes+and+Rough+Drafts

Notes: The system: excretes wastes, the skin is part of it too because it contains sweat to help regulate the concentration in ones body, liver and the kidneys are part of it, bile: used for breaking down wastes [|kidneys]

[|about kidneys]

Functions of the System collect water and filter body fluids remove and concentrate waste products of the body fluids and return other substances to body fluids as necessary for homeostasis eliminate excretory products from the body

 The excretory system's job is to bring the wastes out of your body. If the wastes are not carried out, then the excretory system could get some diseases. The skin, intestines, kidneys, liver, lungs, and sweat glands are the main organs in the excretory system.The skin excretes water and salt from the body, the lungs excrete carbon dioxide from the burning glucose, the liver and gall bladder excrete bilirubin, and the kidneys excrete urea. One disease is kidney disease. That is the build up of wastes in your system. Some cases of kidney disease can be treated with medication. But if the disease is more severe, then the patient might be put on a dialysis machine. That is when your blood is pumped through a dialysis machine that filters the waste from the blood and returns the clean blood. Some patients have to spend near 60 hours on a dialysis machine.

The most radical treatment is a kidney transplant. Healthy people can live with only one kidney. In a transplant, the healthy donated kidney is put in the abdomen of the patient and attached to the blood vessels and bladder. The patient's original kidneys aren't removed from the body.  The excretory system is a system of organs that removes waste products from the body. When cells in the body break down proteins (large molecules that are essential to the structure and functioning of all living cells), they produce wastes such as urea (a chemical compound of carbon, hydrogen, nitrogen, and oxygen). When cells break down carbohydrates (compounds consisting of carbon, hydrogen, and oxygen and used as a food), they produce water and carbon dioxide as waste products. If these useless waste products are allowed to accumulate in the body, they would become dangerous to the body's health. The kidneys, considered the main excretory organs in humans, eliminate water, urea, and other waste products from the body in the form of urine. Other systems and organs in the body also play a part in excretion. The respiratory system eliminates water vapor and carbon dioxide through exhalation (the process of breathing out). The digestive system removes feces, the solid undigested wastes of digestion, by a process called defecation or elimination. The skin also acts as an organ of excretion by removing water and small amounts of urea and salts (as sweat). 

Words to Know
 **Hemodialysis:  ** Process of separating wastes from the blood by passage through a semipermeable membrane.  **<span style="background-color: rgb(0, 0, 0);"><span style="color: rgb(255, 60, 0);">Nephron:  **<span style="background-color: rgb(0, 0, 0);"><span style="color: rgb(255, 60, 0);"> Filtering unit of the kidney. <span style="background-color: rgb(0, 0, 0);"><span style="color: rgb(255, 60, 0);"> **<span style="background-color: rgb(0, 0, 0);"><span style="color: rgb(255, 60, 0);">Urea:  **<span style="background-color: rgb(0, 0, 0);"><span style="color: rgb(255, 60, 0);"> Chemical compound of carbon, hydrogen, nitrogen, and oxygen produced as waste by cells that break down protein. <span style="background-color: rgb(0, 0, 0);"><span style="color: rgb(255, 60, 0);"> **<span style="background-color: rgb(0, 0, 0);"><span style="color: rgb(255, 60, 0);">Ureter:  **<span style="background-color: rgb(0, 0, 0);"><span style="color: rgb(255, 60, 0);"> Tube that carries urine from a kidney to the urinary bladder. <span style="background-color: rgb(0, 0, 0);"><span style="color: rgb(255, 60, 0);"> **<span style="background-color: rgb(0, 0, 0);"><span style="color: rgb(255, 60, 0);">Urethra:  **<span style="background-color: rgb(0, 0, 0);"><span style="color: rgb(255, 60, 0);"> Duct leading from the urinary bladder to outside the body through which urine is eliminated. The waste-containing fluid that remains in the nephrons is called urine. Urine is 95 percent water, in which the waste products are dissolved. A pair of tubes called ureters carry urine from the kidneys to the urinary bladder. Each ureter is about 16 to 18 inches (40 to 45 centimeters) long. The bladder is a hollow muscular sac located in the pelvis that is collapsed when empty, but pear-shaped and distended when full. The bladder in an adult can hold more than 2 cups (0.6 liters) of urine. The bladder empties urine into the urethra, a duct leading to outside the body. In males, the urethra is about 8 inches (20 centimeters) long. In females, it is less than 2 inches (5 centimeters) long. A sphincter muscle around the urethra at the base of the bladder controls the flow of urine between the two. The volume of urine excreted is controlled by the antidiuretic hormone (ADH), which is released by the pituitary gland (a small gland lying at the base of the skull). If an individual perspires a lot or fails to drink enough water, special nerve cells in the hypothalamus (a region of the brain controlling body temperature, hunger, and thirst) detect the low water concentration in the blood. They then signal the pituitary gland to release ADH into the blood, where it travels to the kidneys. With ADH present, the kidneys reabsorb more water from the urine and return it to the blood. The volume of urine is thus reduced. On the other hand, if an individual takes in too much water, production of ADH decreases. The kidneys do not reabsorb as much water, and the volume of urine is increased. Alcohol inhibits ADH production and therefore increases the output of urine.
 * <span style="background-color: rgb(0, 0, 0);"><span style="color: rgb(255, 60, 0);">Antidiuretic hormone: **<span style="background-color: rgb(0, 0, 0);"><span style="color: rgb(255, 60, 0);"> Chemical secreted by the pituitary gland that regulates the amount of water excreted by the kidneys.

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