Excretory System PDF

The Excretory System Excretory system - Get rids of most cell wastes. EXCRETION is the process of removing wastes and excess water from the body. Although the kidneys are the main organs of excretion, other organs also excrete wastes like your skin, lungs, liver, and large intestine also help remove...

The Excretory System Excretory system - Get rids of most cell wastes. EXCRETION is the process of removing wastes and excess water from the body. Although the kidneys are the main organs of excretion, other organs also excrete wastes like your skin, lungs, liver, and large intestine also help removes waste. - Excretory System – removes excess H2O (water), urea, CO2 (carbon dioxide), and other wastes from our blood. Excretion is the process by which metabolic wastes are eliminated to maintain homeostasis. homeostasis. - a self-regulating process by which a living organism can maintain internal stability while adjusting to changing external conditions - -A state of balance among all the body systems needed for the body to survive and function correctly The Skin The skin excretes excess water, salts, and a small amount of urea in sweat. By releasing sweat in very small amounts, this process eliminates wastes even when you may not think you’re sweating. The blood transports carbon dioxide, a waste product of cellular respiration, from the body cells to the lungs. When you exhale, your lungs excrete carbon dioxide and small amounts of water vapor. Removes waste through perspiration(the process of sweating) Think of a time when you were playing under the sun. Did you feel sweat run down your face? ✶ Skin – excretes water, as sweat, which contains some trace chemical wastes, including urea. Your blood transport wastes to the sweat glands in your skin. This gland add water to the waste to produce sweat. Sweat or perspiration is made of water and other wastes such as dissolved mineral salts. The sweat moves through tubes and goes out tiny openings on the surface of your skin called PORES. You know that carbon dioxide passes from blood into the air sacs of your lungs. When you exhale, you get rid of carbon dioxide. You learned that your cells produce carbon dioxide during respiration.Lungs – filter out CO (carbon dioxide) and water from the blood. 2 Removes waste through Respiration You know that some parts of the food that you eat are not digested and become wastes. Solid undigested wastes are passed through the large intestine. This wastes are removed as feces when you defecate. Removes waste through defecation (the discharge of feces from the body.) The Liver - The liver regulates most chemical levels in the blood and excretes a product called bile. This helps carry away waste products from the liver. One of the liver’s main activities is the conversion of nitrogen wastes, a product of protein breakdown, into less toxic urea. Urea is then transported through the blood to the kidneys for elimination from the body. - Convert ammonia (NH3) (ammonia is a colourless gas with a distinctive pungent smell.)into less toxic urea that is excreted through urine. Removes waste by excretion The Kidneys The kidneys are a pair of fist-sized organs and bean-shaped located on either side of the spinal column near the lower back. Through a complex filtering process, the kidneys remove excess water, urea, and metabolic wastes from the blood (Urine). The Kidneys Ureters transport urine from the kidneys to the urinary bladder, where it is stored until it is released through the urethra. ✶ Kidneys – filter out excess water and urea ✶ Removes waste by urination (the discharge of urine from the body) I. The Kidneys ✶ Every drop of blood in your body is filtered by your kidneys about 300 times per day! ✶ Kidneys eliminate urea, minerals and excess water. ✶ Kidneys regulate the amount of water we need to maintain in our bodies. (Homeostasis) Real Human Kidneys The kidneys are part of the urinary system which removes waste and excess water from the blood. Each kidney has tiny tubes that filter your blood. This wastes form a liquid called URINE. The urine flows into tubes called URETERS that lead to the URINARY BLADDER this bladder stores urine until it leaves the body. Urine passes out of the body through a tube called URETHRA a vein carries the cleaned blood from each kidney back into your circulatory system. Kidneys – filter wastes and excess water from the blood. Ureters – tubes that take urine from the kidney to the urinary bladder. Urinary Bladder – a sack that stores urine. Urethra – small tube through which urine leaves the body. Nephrons - functional units of kidney where it produce and remove urine using this complex system with more than 2 millions tiny filters Parts of the waste Excretory system process 1. skin SWEAT, (SALT) PERSPIRATION 2. lungs CARBON DIOXIDE, RESPIRATION WATER 3. kidneys URINE/UREA URINATION 4. large intestine FECES DEFECATION 5. liver EXCRETION UREA What happens to people whose kidneys stop working? Medicines and changes in diet help some kidney problems. Dialysis is needed when kidneys stop working completely. Dialysis is an artificial cleaning of the blood, through the use of an external machine that filters waste and extra fluid from the blood (and then sends it back in). A long-lasting treatment for faulty kidneys is get a transplant of a new kidney. Kidney Transplant In this procedure, a doctor cuts out the damaged kidney and inserts a new, healthy kidney from someone else. If all goes well, the patient can lead a normal life. (People need only one working kidney to stay alive). Transplants are not always easy or successful, however. Part of the problem is that the body tries to reject organs and tissues that are not its own. To help the body accept a new kidney, the doctor may prescribe special drugs. It also helps if the kidney comes from a close relative of the patient. How does the bladder know when it is time for you to go? When your bladder becomes too full, it sends a message to your brain that communicates this. You feel the need to pee and start looking for a place to do it. When the time and place are right (hopefully in the restroom), your brain orders the muscles around your bladder to start squeezing and for the circle of muscles at the bottom of your bladder to open. Urinary System : Common Diseases and Disorders 1. Kidney Stones Kidney stone is mineral buildup in the kidney tissue. Kidney stones may obstruct the flow of urine and may lead to infection. Symptoms may include fever, chills, spasms, and acute pain. If the stones is large enough to block the ureter and obstruct the flow of urine from the kidney, it must be removed by surgery Kidney Disorders—Kidney Stones Substances such as calcium, magnesium, or uric acid salts in the urine can crystallize and form kidney stones. When kidney stones block a ureter, they cause pain. Kidney stones are often treated using ultrasound waves, which pulverize the stones into smaller fragments that are eliminated in the urine. Kidney Disorders—Kidney Damage High blood pressure and diabetes cause most cases of kidney damage. Excessive blood pressure damages the delicate filtering mechanism, and high blood sugar causes the kidneys to filter more blood than normal. Over time, the tubules weaken, and the kidneys may fail to keep up with the demands placed upon them. Kidney Disorders—Kidney Failure When kidneys can no longer cleanse the blood and maintain homeostasis, a person is said to be in kidney failure. A patient with kidney failure must receive dialysis or undergo a kidney transplant. During dialysis, a machine performs the role of the kidneys. The patient’s blood is pumped through the machine, cleansed, and pumped back into the body. Kidney Disorders—Kidney Failure In transplantation, a patient receives a kidney from a compatible donor. Fortunately for the donor, a person can survive with just one healthy kidney. Unless the patient’s diseased kidneys are causing infection or high blood pressure, they are left in place when a healthy kidney and ureter are transplanted from a donor. URINARY TRACT INFECTION (UTI) Bacterial Infection can affect and irritate any part of the urinary tract including the kidneys, ureters, urinary bladder, and urethra. A person with UTI may experience frequency of urination, pain in urination, and lower back pain. In severe cases, presence of blood and pus in the urine may be observed. A person with UTI might experience fever, chills. Treatment of UTI includes antibacterial and urinary antiseptic drugs. When the kidney fail to function in filtering and excreting wastes from the blood, uremia develops. Due to kidney failure, wastes accumulate in the blood. This leads to poisoning of the blood. Symptoms of uremia include fatigue, vomiting,muscle cramps, and weight loss. The wastes from the blood should be removed through dialysis Chronic Renal Failure is the permanent loss of kidney function. It may be caused by certain conditions like diabetes, hypertensions, and atherosclerosis. Renal failure may be also caused by overexposure to some toxins or medications. Its symptoms include swelling, weakness, fatigue, feeling cold, shortness of breath, changes in urination, itchy dry skin, sore legs, loss of taste and vomiting. This disease is treated through hemodialysis and kidney transplant. In HEMODIALYSIS, the blood from a person’s body is filtered to remove wastes and toxins using a kidney dialysis machine. Outperforming a KIDNEY TRANSPLANT, a surgeon replaces a damaged kidney with a close-match kidney from donor. Caring for the Excretory System Every system in the body depends on the Excretory system to remove wastes from our body. You can keep your excretory system healthy by: 1. Drinking plenty of water 2. Having a balanced diet 3. Eating plenty of fruits and vegetables 4. Exercising regularly 5. Practicing proper hygiene 6. Not holding back the need to urinate