Excretory System Bobby Singh & Chudi Mbanefo

1. Excretory System Bobby Singh & Chudi Mbanefo

2. The Kidney 1. Function • The main function of the kidney is to maintain homeostasis of the blood • removes toxins created by metabolism or ingested in diet • removes excess water • Renal Pelvis sends all produced waste (urine) to the ureter to be released • Urine flows down the ureter to the bladder where it is stored until release • When bladder is ready to release urine, the urethra opens and allows the bladder to empty

3. The Kidney (cont.) Structure • Every human has TWO kidneys made up of millions of Nephrons. • Renal Artery carries in blood with waste • Renal Vein carries out blood without waste • There are three parts in a kidney: • renal cortex • renal medulla • renal pelvis • RENAL: pertaining to the kidney • Major calyces are found all throughout the kidney and carry all collected waste

4. The Renal Structures • Renal Cortex: • Outer layer of kidney, its extensions, renal columns, extend into the renal medulla • part of the kidneys made of nephrons and blood vessels. • main function is to purify the blood and clear the body of waste products. • located between the capsule and the medulla and can be recognized by its pale color. • Renal Medulla: • Located deep to the cortex and • The inner most portion of a kidney • Consists of multiple renal pyramids (cone shaped) • Tips of the cones (papillae) project into the minor calyces of the renal pelvis.

5. The Renal Structures (cont.) • Blood vessels from the renal artery are found on the border of the medulla and provide circulation for the kidney • blood passes through the medulla, the last stop for blood going through the kidney 3. Renal Pelvis: • where flow of the urine begins • connects the main body kidney to the ureter • place where all the major calyces meet up to get down

6. The Nephron Basic functional unit of the kidney • made up of a knot of coiled capillaries • Glomerulus • Small blood vessel that looks like a ball of yarn. • The filtering actually occurs in the glomerulus. • Acts as a filter, keeping in normal proteins and cells and letting out wastes. • Tubule • Also called the renal or kidney tubule, is the tube where the wastes filtered out from the glomerulus pass through Function • Removes extra, unnecessary water, wastes and other substances from your blood. • Replenishes substances like sodium, potassium or phosphorus whenever any of these run low in your body.

7. The Ureter Ureter Structure: • tubes made of smooth muscle • when fully developed, ureters are usually 10–12in long (diameter of ureters are half the diameter of an average capillary!) Ureter Function: • pump urine from the kidneys to the urinary bladder • connects to kidney by way of the renal pelvis • In males, the ureter is found on genital-fold while in females it is found on the uterosacral ligament.

8. The Bladder Breaking Down the Urge • large sack of smooth muscle that holds urine until the body is ready, or forced, to release it • stretch receptors in the sack create the “I GOTTA PEE NOW,” feeling • When emptied the bladder is about the size and shape of a pear, the walls collapse into folds called rugae • the average human bladder can hold 400-600 mL Disorders/Conditions • Cystitis: also called Painful Bladder Syndrome (PBS) inflammation in the bladder causing chronic pain • Urinary Retention: Urine does not exit the bladder consistently due to issues with muscle in the bladder. The bladder may swell to hold more than a quart of urine. • Cytocele: (women only) Weakened pelvic muscles, usually from childbirth, allow the bladder to press on the vagina. Creates complications with urination. • Bedwetting: chronic urination while sleeping common in children up to 5 years old. In older cases it is considered “being a little baby.” Nothing to be ashamed of though.

9. In females, the urethra is 1.5 inches, but in males, they reach out to be 8 INCHES! The Urethra • Release path from the bladder for the created urine • Has two sphincters to regulate the flow of urine by opening and closing • Internal: involuntary/no control, smooth muscle that is the same in both males and females • External: voluntary/some control, skeletal muscle that differs by gender • females- made up of three muscles that work together that constrict together to squeeze the vagina and the urethra at the same time • males- functions the same as the internal sphincter

10. Kidney Diseases • Kidney Failure • takes place when kidneys begin to not function properly • Results in accumulation of waste products and toxic products • Kidney begins to function less than 20% • May cause permanent damage to body cells, tissues, and organs • Kidney Stones • Small hard deposits forming inside the kidney • Usually form when urine becomes concentrated, allowing minerals to crystallize and stick together. • No permanent damage is caused and a simple way to rid the stone is by drinking lots of water and taking pain medications. • May need surgery in certain cases.

11. Kidney Diseases • Diabetic Kidney Problems • Diabetes causes your blood sugars to be too high • Kidneys are unable to properly filter the rising amounts of sugar • One of the main causes of kidneys failure • Urinary Tract Infection (UTI) • Can occur in any part of your urinary system (kidneys, ureters, bladder and urethra) • Caused by germs getting into the urinary tract system through the urethra • Women are at greater risk to develop UTI than men because of their shorter urethra • Antibiotics are the basic treatment for these infections • If not treated quick enough, it can damage your kidneys and lead to a kidney infection as well

12. Works Cited • "The Bladder (Human Anatomy): Function, Picture, Location, Definition." WebMD. WebMD, 1 July 2009. Web. 11 May 2013. <http://www.webmd.com/urinary-incontinence-oab/picture-of-the-bladder>. • "Excretory System." ScienceDaily. ScienceDaily, n.d. Web. 11 May 2013. <http://www.sciencedaily.com/articles/e/excretory_system.htm>. • Mangusan, David, Jr. "Kidney Health Care (KHC)." The Nephron. N.p., n.d. Web. 11 May 2013. <http://www.kidneyhealthcare.com/2010/12/nephron-structure-function-nephron.html>. • Riebe, Mary. "The Structure of the Kidney." The Structure of the Kidney. N.p., n.d. Web. 12 May 2013. <http://www.wisc- online.com/objects/ViewObject.aspx?ID=NUR2503>. • Spence, Alexander P. Basic Human Anatomy. Redwood City, CA: Benjamin/Cummings Pub., 1982. Print. • Walker, Richard. Firefly Guide to the Human Body. Toronto: Firefly, 2004. Print. • "What Is the Renal Cortex?" WiseGEEK. WiseGEEK, n.d. Web. 11 May 2013. <http://www.wisegeek.org/what-is-the-renal- cortex.htm>. • YouTube. Perf. Khan Academy. YouTube. YouTube, 03 Mar. 2010. Web. 12 May 2013. <http://www.youtube.com/watch?v=cc8sUv2SuaY>.