Unit 4 Notes

2,085 views

Published on

Published in: Education
0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total views
2,085
On SlideShare
0
From Embeds
0
Number of Embeds
543
Actions
Shares
0
Downloads
0
Comments
0
Likes
0
Embeds 0
No embeds

No notes for slide
  • Your kidneys are important because they do these essential things. Regulate water For your body to work properly, it must contain just the right amount of water. One of the important jobs of the kidneys is to remove excess water from the body or to retain water when the body needs more. Remove wastes Many of the substances in the blood and body fluid must be kept at the correct level for the body to function properly. For example, sodium and potassium are minerals which come from food. These minerals are needed by the body for good health, but they must be kept at specific levels. When the kidneys are working properly, excess minerals, such as sodium and potassium, are excreted from the body in the urine. The kidneys also help to regulate the levels of other minerals, such as calcium and phosphate, which are important for the formation of bone. Wastes, such as urea and creatinine, must also be removed from the body. Urea and other wastes are made when the body breaks down protein, such as meat. Creatinine is a waste product of the muscles. As kidney function decreases, the levels of urea and creatinine in the blood increase. Many waste products are toxic (poisonous) if they are not removed from the body fluids. For example, when certain drugs are taken, chemical wastes are produced which must be removed from the body by the kidneys. Produce hormones Normal kidneys also make important chemical messengers called hormones. These hormones circulate in the bloodstream and regulate some body functions such as blood pressure, the making of red blood cells, and the uptake of calcium from the intestine. These hormones will be discussed later in the lesson and in Module 8
  • Your kidneys are important because they do these essential things. Regulate water For your body to work properly, it must contain just the right amount of water. One of the important jobs of the kidneys is to remove excess water from the body or to retain water when the body needs more. Remove wastes Many of the substances in the blood and body fluid must be kept at the correct level for the body to function properly. For example, sodium and potassium are minerals which come from food. These minerals are needed by the body for good health, but they must be kept at specific levels. When the kidneys are working properly, excess minerals, such as sodium and potassium, are excreted from the body in the urine. The kidneys also help to regulate the levels of other minerals, such as calcium and phosphate, which are important for the formation of bone. Wastes, such as urea and creatinine, must also be removed from the body. Urea and other wastes are made when the body breaks down protein, such as meat. Creatinine is a waste product of the muscles. As kidney function decreases, the levels of urea and creatinine in the blood increase. Many waste products are toxic (poisonous) if they are not removed from the body fluids. For example, when certain drugs are taken, chemical wastes are produced which must be removed from the body by the kidneys. Produce hormones Normal kidneys also make important chemical messengers called hormones. These hormones circulate in the bloodstream and regulate some body functions such as blood pressure, the making of red blood cells, and the uptake of calcium from the intestine. These hormones will be discussed later in the lesson and in Module 8
  • Unit 4 Notes

    1. 1. Unit 4Excretion & Waste Management(Chapter 16: Page 303 – 317)
    2. 2. EXCRETION VIDEO
    3. 3. Excretion• Every metabolic process in the human body uses energy and generates wastes.• The process of getting rid of metabolic wastes is called excretion.• There are many organs and systems responsible for excretion: – the skin – the lungs – the liver – the kidneys
    4. 4. Excretion
    5. 5. Excretion and Homeostasis• Cells produce water and carbon dioxide as by-products of metabolic breakdown of sugars, fats, and proteins.• Chemical groups such as nitrogen, sulfur, and phosphorous must be stripped, from the large molecules to which they were formerly attached, as part of preparing them for energy conversion.• Excretion aids homeostasis by removing metabolic wastes and regulating the salt and water balance.
    6. 6. Excretion and Homeostasis• The blood picks up carbon dioxide, excess salts, nitrogen compounds, and any excess water that may be present in the interstitial fluid and carries them to the excretory organs, which channel the wastes out of the body.• Therefore, the excretory system regulates volume of internal body fluids as well as eliminates metabolic wastes from the internal environment.
    7. 7. Excretion and Homeostasis • Several organs take part in human excretion. The skin, lungs, liver, and the kidneys. • The metabolic wastes produced and the organs that excrete them are summarized in the chart on the next slide.
    8. 8. Organ of Wastes Formed From Excretion1. Carbon Cellular Respiration lungsDioxide2. Water Cellular Respiration & kidneys, Dehydration Synthesis skin, lungs3. Nitrogenous Metabolism of Proteins (Amino kidneys,Wastes Acids) liver, skina) Ammonia deamination of amino acids by liver(extremely toxic) the liverb) Urea ammonia combined with carbon kidneys, dioxide skin product of the breakdown ofc) Uric Acid liver nucleic acids, such as DNA4. Mineral Salts Metabolism of Various Food kidneys,(NaCl, KSO4) Substances skin
    9. 9. Skin and Homeostasis• The skin has many functions in the body with excretion being one of them.• Your skin has approximately 2 million sweat glands.
    10. 10. Skin and Homeostasis• These glands secrete sweat continuously, even when you are not exercising.• Sweat consists primarily of water, along with salts, and some urea (nitrogen-based waste). These materials pass from the blood vessels in the skin into the sweat glands. The wastes travel up the tubules and onto the surface of the skin through tiny openings called pores.• The wastes form perspiration on the skin, which eventually evaporates. The solid wastes in the perspiration remain on the surface of the skin or on clothing.
    11. 11. Skin and Homeostasis
    12. 12. Excretion in the Lungs• Carbon dioxide and water are produced by all cells during cellular respiration.• The blood carries these to the lungs.• Carbon dioxide diffuses into the alveoli and is removed from the body when we exhale.• Some water also leaves the lungs as water vapour.
    13. 13. Excretion in the Lungs
    14. 14. The Role of the Liver in Excretion• Some proteins and other nitrogenous compounds are broken down in the liver by a process called deamination.• The extraction of energy from proteins produces ammonia (NH3), a highly toxic substance. The liver converts ammonia to a non-toxic substance called urea by combining it with carbon dioxide.• The blood then delivers urea to the kidneys, where it is excreted.
    15. 15. The Role of the Liver in Excretion• The liver also breaks down red blood cells.• The liver is also responsible for removing potentially hazardous chemicals from the blood. It "detoxifies" the blood.• The liver breaks down harmful and foreign substances, such as many ingested poisons and drugs after they are absorbed by the digestive system and before they reach the rest of the body.
    16. 16. The Role of the Liver inExcretion
    17. 17. The Urinary System
    18. 18. The Urinary System• The human urinary system consists of two kidneys, two ureters, the urinary bladder, and the urethra. Normally, there are two of kidneys, one on either side of the spine under the lower ribs. The ureters lead from the kidneys to the urinary bladder, which lies low in the abdominal cavity. The urethra extends from the bladder to the exterior of the body, carrying urine through the urogenital organs, either the penis or vagina.
    19. 19. Importance of Kidneys Your kidneys are important because they do these essential things. 1. Regulate water 2. Remove wastes 3. Produce hormones
    20. 20. Importance of Kidneys
    21. 21. Structure of Kidneys• Kidneys are reddish brown in colour and shaped like kidney beans. Each kidney is about the size of your clenched fist. If you were to cut a kidney in half, you would see the following parts: – renal capsule - a thin, outer membrane that helps protect the kidney – cortex - a lightly colored outer region – medulla - a darker, reddish-brown, inner region – renal pelvis - a flat, funnel shaped cavity that collects the urine into the ureters
    22. 22. The Nephron
    23. 23. The Nephron• The working units of the kidney are microscopic structures called nephrons. Each kidney contains about one million nephrons.• A nephron contains a network of capillaries called the glomerulus, which filters blood into a cup-shaped structure known as the Bowmans capsule. The filtrate then passes into a series of tubules. Water and waste products are separated from the blood by the filtering process and the flow into and out of the tubules. Much of the water is reabsorbed by the tubules and the wastes are concentrated into urine.
    24. 24. The Nephron
    25. 25. The Nephron The nephron is a tube; closed at one end, open at the other. It consists of a: – Glomerulus - coiled capillaries inside the Bowmans capsule. – Bowmans (Glomerular) capsule - closed end at the beginning of the nephron. It is located in the cortex. – Proximal convoluted tubule - first twisted region after the Bowmans capsule. It is also in the cortex.
    26. 26. • Loop of Henle - long, loop after the proximal tubule. It extends from the cortex down into the medulla and back.• Distal convoluted tubule - second twisted portion of the nephron after the loop of Henle. It is also in the cortex.• Collecting duct - long straight portion after the distal tubule that is the open end of the nephron. It extends from the cortex down through the medulla.
    27. 27. The nephron also has a unique and rich bloodsupply compared to other organs. They arelisted below. – Renal artery - supplies blood to the kidney from the circulatory system – Renal vein - returns blood from the kidney to the circulatory system – Afferent arteriole - connects the renal artery with the glomerular capillaries. – Efferent arteriole - connects the glomerular capillaries with the peritubular capillaries. – Peritubular capillaries - located after the glomerular capillaries and surrounding the proximal tubule, loop of Henle, and distal tubule.
    28. 28. Kidney Function• Many of the substances in the blood and body fluids must be kept at the correct level for the body to function properly. Regulating the composition of these fluids involves the following: – Keeping the concentrations of various ions and other important substances constant. – Keeping the volume of water in your body constant. – Removing wastes from your body. – Keeping the acid/base concentration of your blood constant.
    29. 29. Kidney FunctionThe kidney performs these functions by a combination of:• Filtration - the passage of substances through the capillaries of the glomerulus into Bowmans capsule.• Reabsorption - the transfer of essential solutes and water from the nephron back into the blood• Secretion - the movement of materials from the blood back into the nephron.
    30. 30. The Kidney & the Nephron
    31. 31. Formation of Urine• The nephron makes urine by: – filtering the blood of its small molecules and ions and then – reclaiming the needed amounts of useful materials. – Surplus or waste molecules and ions are left to flow out as urine.
    32. 32. Formation of UrineThe steps include:• Blood enters the glomerulus under pressure.• This causes water, small molecules (but not macromolecules like proteins) and ions to filter through the capillary walls into the Bowmans capsule. This fluid is called the filtrate.• The filtrate collects within the Bowmans capsule and then flows into the proximal tubule.• Here large amounts of glucose, amino acids, and salts are reabsorbed by active transport.• As these solutes are removed from the filtrate, a large volume of the water follows them by osmosis.
    33. 33. Formation of UrineThe steps include:• As the fluid flows into the loop of Henle, it is approximately isotonic to the blood. Here more sodium ions are pumped out, but water does not follow them. So, the interstitial fluid becomes very hypertonic and the fluid within the loop of Henle becomes hypotonic.• In the distal tubules, more sodium is reclaimed by active transport. The amount is closely regulated, chiefly by the action of the hormone aldosterone. Water may follow by osmosis.
    34. 34. Formation of UrineThe steps include:• The final adjustment of the water content of the body occurs in the collecting ducts.• The permeability of this tubule can vary depending upon the bodies need.
    35. 35. Formation of UrineReabsportion of Water: – Hormonal control of collecting duct permeability • Blood too concentrated in solutes –Posterior pituitary releases ADH (antidiuretic hormone) »Increases permeability of collecting duct to water »More water is reabsorbed from filtrate (urine) »Small volume of hypertonic urine produced
    36. 36. Formation of UrineReabsorption of Water: – Blood too diluted –ADH shut off –Collecting duct decreases permeability to water –More water lost in urine –High volume of dilute urine produced
    37. 37. Formation of Urine• Diuretics – Increase flow of urine – Alcohol • Shuts off ADH • Dehydration causes hangover – Caffeine • Increases glomerular filtration rate • Decreases tubular reabsorption of sodium
    38. 38. Kidney Failure• In the event of kidney failure due to infection or disease, the kidney can no longer remove metabolic waste products from the body. Excretion of metabolic waste is a vital function and their accumulation will result in eventual death.• There are a number of known causes of kidney failure but in quite a few people, the cause is never found. The most common causes are diabetes, high blood pressure and a painless inflammation of the kidneys called glomerulonephritis. There is a progressive loss of the filtering units (nephrons) in the kidney.
    39. 39. Kidney Failure• If the kidneys are damaged, they may carry on producing urine but become less efficient at removing waste products from the blood. Instead, the waste products continue to circulate and build up in the bloodstream.• At the same time, without the hormones that a healthy kidney would produce, the bone marrow becomes less efficient at producing red cells, so anaemia develops.
    40. 40. Kidney Failure• For some patients, this may be a very gradual process. Over time, however, it can cause quite a wide range of symptoms. Not everyone will experience all the symptoms. Also, because it can be such a gradual process, some people don’t even realize the effect the symptoms are having until - with treatment - they begin to feel better.• There are two solutions to the problem of kidney malfunction or failure: – Kidney transplant (the best solution) – Kidney dialysis
    41. 41. Dialysis• Dialysis is a way to clean the blood by removing wastes and excess water. There are two types: hemodialysis and peritoneal dialysis.• Hemodialysis – During hemodialysis, the blood is passed through an artificial kidney. The artificial kidney cleans the blood in almost the same way that healthy kidneys do. The treatment is performed usually three times a week. It can take between three and five hours each time and is called a run.
    42. 42. Dialysis – Hemodialysis continued• Hemodialysis – Hemodialysis can be done in a hospital dialysis unit, in a self- care centre (with some assistance from the staff), or at home with the aid of a partner. Special training is required for self- care or home dialysis.
    43. 43. Dialysis• Peritoneal Dialysis – Peritoneal dialysis works on the same principle as hemodialysis, but the blood is cleaned inside the body rather than through an artificial kidney. Your abdomen or "belly" has a peritoneal cavity lined by a thin membrane called the peritoneum that surrounds the intestines and other internal organs.
    44. 44. Dialysis – Peritoneal Dialysis continued• Peritoneal Dialysis – In peritoneal dialysis, your peritoneal cavity is filled with a special dialysis fluid. Excess water and wastes pass through the peritoneum into the dialysis fluid. This fluid is then drained from the body and discarded. The process is repeated between four to five times a day or a machine called an automatic cycler can perform exchanges while you sleep. In most cases, this treatment can be performed without assistance, at home or at work. Peritoneal dialysis is sometimes done in a hospital, but more often, you are trained to do this independently at home.
    45. 45. Kidney Transplant• A kidney transplant is a surgical procedure in which a healthy donated kidney is transplanted into another body. A successful kidney transplant will allow the person to return to a more normal lifestyle and will free them from dialysis treatments.• There are two types of kidney transplants: a living donor transplant and a cadaveric transplant.
    46. 46. Kidney Transplant• A Living Donor Transplant – In a living donor transplant, a kidney from a donor, usually a blood relative is transplanted. The most suitable donors are usually members of the immediate family. – The donors blood group and tissue type must be compatible, and extensive medical tests will be done to determine the health of the donor. People who donate a kidney can live a normal life with one kidney and there are few risks to healthy donors. – Living donor transplants have a 90 to 95% success rate. That means that after one year, 90 to 95 of every 100 transplanted kidneys are still working.
    47. 47. Kidney Transplant• A Cadaveric Transplant – A transplant from a non-living donor is called a cadaveric transplant. In this type of transplant, a healthy kidney from someone who has died suddenly is transplanted. Before a cadaveric donors organs can be transplanted, a series of medical tests is done to determine if they are healthy. In addition, the family of the donor must consent to organ donation. – After a series of tests, the person will be put on a transplant waiting list until a kidney is found that is compatible. – Cadaveric transplants have an 80 to 85% success rate.
    48. 48. Kidney Transplant
    49. 49. You are a doctor Imagine you are a new doctor who has receivedtest results for a patient showing signs of renalfailure. Your task is to prepare an explanationfor the patient on what the problem is, within thecontext of what normal kidney function lookslike, and what the treatment options are(dialysis and transplant). You must describe theoptions in detail, including pros and cons. Yourpreparation will take the form of a written report,which will be shared with fellow doctors toconfirm yourinformation. This patient is in dire need of help,therefore you must have this report completedASAP.
    50. 50. You are a doctor Assessment:Students must prepare a written submission, whichwill be evaluated by the teacher. Criteria for thewritten piece includes:• Explanation of kidney function is clear and complete• Appropriate terminology is used• Diagrams are included• Accurate explanation of the consequences or renalfailure are included• Description of treatment option is clear, concise,accurate, understandable by patient and includespros and cons 
    51. 51. Diabetes
    52. 52. Testing for HealthyKidney Function• Healthy kidneys remove wastes and excess fluid from the blood.• Blood tests show whether the kidneys are failing to remove wastes.• Urine tests (urinalysis) can show how quickly body wastes are being removed and whether the kidneys are leaking abnormal amounts of protein.
    53. 53. Making the StrangeSound Familiar• Make the following comparison: – The excretory system is like an automobile because . . . – The excretory system is not like an automobile because . . . – The excretory system is like an house because . . . – The excretory system is not like an house because . . .
    54. 54. Print Master• Your Text here• Lorem ipsum dolor sit amet, consectetuer adip iscing elit, sed diam no n u mmy nibh euismod tincidunt ut laoreet do lore magna aliquam er at v olut pat. Ut wisi enim ad mi ni m venia m, quis nostrud exerci tatio n ulla mco rper susc ip it lobor tis nisl ut aliquip ex ea commodo cons equat.• Duis autem vel eum iriure dolor in hendrerit in vulputate velit esse mo les tie consequat, vel illum dolore eu feugiat nulla fac ilisis at vero eros et ac cumsan et iusto odio dign issim qui bla ndit praesent lup tatum zzril dele nit augue duis dolore te fe ug ait nulla facilisi

    ×