Human Excretory System

1. Human Excretory System composed of kidney-functional unit of a kidney- nephron) lungs (alveoli) skin (sweat glands) liver

2. WasteProduced from Carbon Dioxide Aerobic Respiration Water Aerobic Respiration Salts Metabolic activities Nitrogenous wastes Breakdown of excess Amino Acids & Proteins types of nitrogenous wastes toxicity Ammonia (NH3) Highly Toxic Urea Moderately Toxic Uric Acid Crystals Minimally Toxic types of metabolic wastes

3. human excretory system waste and what its removed by • carbon dioxide- lungs • water - skin, kidney, lungs • salts - skin, kidney • ammonia - liver • urea -kidney

4. human excretory system • consists of the kidneys, ureters, urinary bladder, urethra and renal circuit (renal arteries and renal veins) • kidney includes an outer cortex, middle medulla and the nephrons • nephrons include a capsule and a looping tubule that joins others to form the collecting ducts, making up the pyramids which empty into the calyces - lead into the renal pelvis • nephrons form urine, which passes from the collecting ducts to the renal pelvis.  The renal pelvis empties into the ureters, which conduct urine to the urinary bladder, and the urethra voids the urine from the body.

5. primary organs of excretion

6. blood and urine flow blood enters the kidneys via renal arteries, and leaves the kidneys via the renal veins wastes removed from the blood leave the kidneys by the ureter

7. kidney Learn the parts Functions of the kidneys • excrete toxins and nitrogenous wastes • regulate chemical levels in blood • maintain water balance • helps regulate blood pressure (renin)

8. label the partson a model

9. label the partson a model 1. Renal Vein 2. Renal Artery 3. Renal Calyx 4. Medullary Pyramid 5. Renal Cortex 12. Renal Column 13. Renal Papillae 14. Renal Pelvis 15. Ureter

10. cross section of human kidney

11. label the parts dissected kidney 1. Renal Capsule 2. Renal Cortex 3. Renal Medulla 4. Renal Pyramid 5. Renal Pelvis 6. Renal Column 7. Renal Calyx 8. Ureter

12. structures

13. other organs • ureters - long narrow tubes with expanded upper end (renal pelvis) located inside each kidney. Function is to drain the renal pelvis to urinary bladder • urinary bladder- elastic muscular organ capable of great expansion. Function si storage of urine and voiding • urethra – passage of urine from bladder to outside of body. Passage of semen from male body

14. formation of urine occurs by a series of three processes that take place in successive parts of the nephron • filtration • reabsorption • secretion

15. the nephron The nephron begins with Bowman's capsules, which surrounds the glomerulus, a ball of capillaries arising from an afferent arteriole of the renal artery.  Leaving the glomerulus is an efferent arteriole, which forms the peritubular capillaries, where reabsorption takes place.  These spread over the nephron to later form a venule that joins others to make up the renal vein.

16. nephron in detail

17. the nephron Bowman's capsule leads to the proximal convoluted tubule, the loop of Henle, and the distal convoluted tubule, which joins a collecting duct.  The afferent arteriole also connects with the distal convoluted tubule, forming the juxtaglomerular complex.

18. Items filtered out of the blood into the Bowman's capsule Glucose (but must be returned to the blood by active transport at the loop of Henle) urea salts water Items that remain in the blood are RBCs WBCs platelets large chemicals like hormones Bowman’s capsule

19. parts of the nephron & functions 1 • Bowman's capsule.  Force filtrationin Bowman's capsule causes much of the water and ions and smaller molecules to leave the blood and enter the proximal convoluted tubule. • The proximal tubule. the peritubular capillaries contain blood in a hyperosmotic state, so much of the water filtrate reenters (reabsorption)the blood by osmosis.  Active transport also returns sodium (chloride following passively), glucose, and amino acids to the blood.

20. parts of the nephron & functions 2 • The loop of Henle. The ascending loop actively transports chloride ions (sodium ions follow passively) into the surrounding area, recycling salt and creating a hyperosmotic state in the kidney medulla.  The hypertonic state is further increased by urea, which diffuses out of the collecting ducts. • The distal tubule.  The active secretionof sodium ions occurs with chloride ions and water passively following.  Potassium ions enter the tubule.

21. parts of the nephron & functions 3 • Collecting ducts.  Water leaves the collecting ducts in response to antidiuretic hormone (ADH), which is secreted by the posterior pituitary in response to osmotic conditions in the blood (actually detected by the hypothalamus).

22. formation of urine

23. wastes - urine The remaining wastes, now called urine are transported out through the collecting tubule to an area known as the renal pelvis (a collecting area) where the urine then passes into the ureter

24. urinalysis physical, chemical, microscopic examination of urine

25. urinalysis physical, chemical, microscopic examination of urine

26. Ammoniacal-Occurs especially during decomposition or urine on standing ("alkaline fermentation") or retention within urinary bladder; may be related to some bacterial infections. Effects of drugs and diet-Many ingested substances will give the urine a distinct odor as ingested asparagus giving urine its characteristic odor. Fecal-Due to contamination with feces or E. coli; often related to bladder-GI tract fistula. Fetid or Putrid-May be caused by diseases of the GU tract. Decomposition of urine containing cystine or pus will have the odor of rotten eggs (H2S). Fruity or Sweetish-Usually due to acetone in diabetic acidosis, starvation or dieting. Urinoid or Faintly Aromatic; Normal Attributed to volatile organic acids most marked in "concentrated" urine specimens. urinalysis - urine odor

27. control of nephron Nephron control is hormonal, with water reabsorption controlled by ADH from the posterior pituitary and sodium chloride reabsorption controlled by aldosterone from the adrenal medulla.  Sodium chloride transport is monitored by the juxtaglomerular complex.  The arteriolar cells secrete renin, which stimulates the adrenal cortex to secret aldosterone.  Aldosterone increases the absorption of sodium chloride and the excretion of potassium.

28. a few disorders of the excretory system Obstructive disorders kidney stones kidney cancer Renal failure - (kidney failure) UTIs - urinary tract infections, often caused by gram-negative bacteria cystitis-bladder infections urethritis-inflammation of the urethra pyelonephritis- inflammation of the kidneys

29. kidney stones • Cause - metabolic disorder involving calcium, proteins and uric acid the build up of these substances into a large deposit (stone) • Symptoms - irritation of the urinary tract, bleeding in the urinary tract, in cases with large stones there can be extreme pain as the stone(s) try to pass through the tract • Treatments - removal by surgical means, breakdown of stones by either physical (ultrasound) or chemical means, dietary changes to reduce chances of stones

30. renal (kidney) failure • Causes - infections, trauma, diabetes, tumors • Symptoms - build up of toxins in the blood stream (urea), jaundice, fatigue • Treatments - dialysis, drug therapy, transplants

31. bladder infections • Causes - infection of the urinary tract • Symptoms - burning sensation in the flanks that can move down from the middle of the back towards the front of the groin, burning sensation while urinating • treatments - antibiotics

32. the excretory system speaks… Roses are redViolets are blueI clean out the systems That's what I doViolets are blueRoses are redWithout the excretory systemWe'd all be dead! by John H.

33. Human Reproductive System If it wasn't for me You wouldn't beI've kept population through many a daySo the human race will stay by Joey F.

34. Human Reproductive System The reproductive system is the system that allows for the continuation of the human species  This system is different in males and females 

35. Human Reproductive System The role of the male’s reproductive system is to manufacture sperm and then to deliver them to the female’s reproductive tract where fertilization may occur 

36. Human Reproductive System The role of the female’s reproductive system is basically the same except that it goes further if the sperm meets an egg.  If fertilization occurs the female reproductive system is designed to nurture and care for the cell that will soon grow into a baby

37. Human Reproductive System • The sperm is produced in the male testis and then travels through a series of ducts to reach the body exterior • The eggs are produced in the ovary of a female.  When a egg is to be expelled or ovulated a “blister forms on the exterior of the ovary.  When the “blister” bursts the egg may be collected by the ends of the fallopian tubes and travels through the fallopian tubes where it can be fertilized by a single sperm

38. Human Reproductive System • If an egg is fertilized it travels down into the uterus where it embeds in the wall of the uterus.  • There it divides rapidly and the cells begin to specialize into the different organs of a pregnancy.  Some of the cells form the amniotic sac while some form the placenta and the umbilical cord.  • Only a small number of these cells will eventually form the fetus

39. Human Reproductive System The scrotum and penis are the male genitalia.  The male gonads, called testis, are tightly coiled tubes surrounded by tissue. Sperms develop in these tubes.  The male gonads are located outside of the body since sperm productions can only occur at about two degrees Celsius lower than normal body temperature. After the sperm are produced they mature and are stored in the epididymis.

40. male reproductive system The male reproductive system also contains three glands that add secretions to the semen.  seminal vesicles prostate gland bulbourethral glands

41. seminal vesicles Sixty percent of semen is secreted by the seminal vesicles.  They lie behind and below the bladder and empty directly into the ejaculatory duct.  The fluid secreted is clear and thick.  It contains mucus, amino acids, and fructose.  The fructose provides energy for the sperm.

42. prostate gland and bulbourethral glands • The prostate gland surrounds the beginning of the urethra in which it secretes its products.  Prostatic fluid is milky, thin, and alkaline in order to balance the acidity of any urine remaining in the urethra and the acidity of vaginal fluids • Bulbourethral glands lie along the urethra below the prostate.  Although their specific function is still unknown, they do secrete a viscous fluid before ejaculation

43. male reproductive system Three layers of spongy tissue comprise the human penis.  When sexually aroused, this tissue fills with blood from the arteries, while the veins are sealed.  This produces an erection. The shaft of the penis is covered in relatively thick skin.  The head, or glans penis, is covered with thinner skin.  This results in extra sensitivity in the glans penis area.

44. Human Reproductive System Ovaries, the female gonads, are located below the digestive system in the abdominal cavity.  Inside each ovary are many follicles which consist of a single egg cell and one or more layers of follicle cells.  Follicle cells protect and nourish the egg cells.  A woman is born with about 400,000 follicles and cannot produce more.

45. Human Reproductive System Ovulation is the process in which an egg is expelled from a follicle.  The egg is expelled directly into the abdominal cavity and is picked up by the fallopian tubes.  Inside the fallopian tubes are cilia which sweep the egg toward the uterus.  At the neck of the uterus is the cervix followed by the vagina whichhas very thin walls, much thinner than those of the uterus.

46. Human Reproduction Before fertilization can occur, the sperm must reach the egg.  Each egg is only viable for 12 to 48 hours and some sperm can survive for as long as 72 hours, but most can only retain their fertilizing power for 12 to 48 hours.  Therefore in order to produce offspring, sex must occur no more than 72 hours before ovulation or no later than 24 hours after.

47. Human Reproduction • The moment of ejaculation, millions of sperm are released into the female’s reproductive tract.  Many are able to swim up through the vagina towards the cervix.  Many are killed by the acidity of the vaginal fluids.   Here thousands of sperm are killed by phagocytes which recognize them as “non-self.”  Of the millions of sperm that are ejaculated, only a few thousand are able to reach the egg.

48. Human Reproduction • Should sperm reach the egg, they cannot immediately fertilize it.  As time must pass for their membranes to become capacitated, or weakened.  This is facilitated by the cervical mucus, and in the following 6-8 hours the sperm are gradually capacitated. • After capacitation has occurred, the acrosomal reaction follows.  This reaction releases enzymes in the area surrounding the egg therefore weakening the intracellural cement that surrounds the egg.  Once weakened a single sperm is allowed to penetrate the egg and fertilize it.

49. STD’s in USA

50. references • Cyber-Anatomy Web site http://library.thinkquest.org/11965/cyber-anatomy_index.html