1. Human Anatomy and Physiology
The Urinary System

2. Functions of Kidney Salt and water balance pH balance
Excretion of nitrogenous waste (ammonia, urea, uric acid, creatinine)

3. Functions of the Kidney
Activation of Vitamin D
Vitamin D made in the skin is converted to Vitamin D3 by the kidney
Active Vitamin D (D3) assists homeostasis by increasing calcium absorption from the digestive tract
Unit 1 - Objective 1

4. Functions of Kidney Maintain salt and water balance
Maintain pH balance
Excretion of nitrogenous waste (ammonia, urea, uric acid)

5. Functions of the Kidney
Release of Erythropoietin by the kidney
Erythropoietin stimulates new RBC production
New RBC’s assist homeostasis by insuring adequate Oxygen and Carbon Dioxide transport
Unit 1 - Objective 1

6. Functions of the Kidney
Release of Renin by the kidney
Renin stimulates the formation of a powerful vasoconstrictor called Angiotensin II
Angiotensin II assists homeostasis by causing vasoconstriction which increases blood pressure
Unit 1 - Objective 1

7. Urinary System Renal artery Renal Vein Kidney Ureter Urinary Bladder
For sphincters, see next slide

8. Kidney Diagram Medulla Calyx Pyramid Renal Vein Cortex Renal Artery
Nephron
Pelvis
Capsule
Ureter

9. Nephron
Structural and functional units of kidney- over 1 million in each kidney!
Nephron composed of
Glomerulus – knot of capillaries
Renal tubule

10. Diagram of Kidney Nephron
Efferent arteriole
Afferent arteriole
Bowman’s capsule
Collecting duct
Proximal convoluted tubule
Glomerulus
Peritubular capillaries
Vasa recta
Decending limb of loop of Henle
Ascending limb of loop of Henle
Distal convoluted tubule
Unit 1 - Objective 4

11. Location of the Glomerulus
Efferent Arteriole
Afferent Arteriole
Bowman’s Capsule
Glomerulus
Proximal Convoluted Tubule

12. Bowman’s Capsule
Efferent Arteriole
DCT
PCT
Macula Densa Cells
Granular Juxtaglomerular (JG) Cells
Afferent Arteriole

13. nephron

14. Diagram of Kidney Nephron
Efferent arteriole
Afferent arteriole
Bowman’s capsule
Collecting duct
Proximal convoluted tubule
Glomerulus
Peritubular capillaries
Vasa recta
Decending limb of loop of Henle
Ascending limb of loop of Henle
Distal convoluted tubule
Unit 1 - Objective 4

15. Normal Urine

16. Abnormal components - Urine
Protein Renal disease, severe anemia Glucose Diabetes mellitus
Blood Renal disease
Hemoglobin Renal disease
Bacteria Infection

17. Urinary System Female Sphincters Male Sphincters
Internal urethral sphincter
External Urethral Sphincter

18. Functions of Nephron Structures
Proximal Convoluted Tubule (PCT)
A thick, constantly actively segment of the nephron that reabsorbs most of the useful substances of the filtrate: sodium (65%), water (65%), bicarbonate (90%), chloride (50%), glucose (nearly 100%!), etc.
The primary site for secretion (elimination) of drugs, waste and hydrogen ions
Unit 1 - Objective 4

19. nephron

20. Diagram of Kidney Nephron
Efferent arteriole
Afferent arteriole
Bowman’s capsule
Collecting duct
Proximal convoluted tubule
Glomerulus
Peritubular capillaries
Vasa recta
Decending limb of loop of Henle
Ascending limb of loop of Henle
Distal convoluted tubule
Unit 1 - Objective 4

21. nephron

22. Functions of Nephron Structures
Decending Limb of the Loop of Henle
freely permeable to water and relatively impermeable to solutes (salt particles)
receives filtrate from the PCT, allows water to be reabsorbed and sends “salty”filtrate on the the next segment. “Saves water and passes the salt”
Unit 1 - Objective 4

23. Functions of Nephron Structures
Ascending Limb of the Loop of Henle
impermeable to water and actively transports (reabsorbs) salt (NaCl) to the interstitial fluid of the pyramids in the medulla. “Saves salt and passes the water.”
the passing filtrate becomes dilute and the interstitium(medulla) becomes hyperosmotic
Unit 1 - Objective 4

24. nephron

25. Functions of Nephron Structures
Distal Convoluted Tubule (DCT)
receives dilute fluid from the ascending limb of the Loop of Henle
Variably active portion of the nephron
When aldosterone (hormone) is present, sodium is reabsorbed and potassium is secreted. Water and chloride follow the sodium.
Unit 1 - Objective 4

26. nephron

27. Functions of Nephron Structures
Collecting Duct
receives fluid from the DCT
variably active portion of the Nephron
when antidiuretic hormone (ADH) is present, this duct will become porous to water. Water from the collecting duct fluid then moves by osmosis into the “salty” (hyperosmotic) interstitium of the medulla.
The last segment to save water for the body
Unit 1 - Objective 4

28. Functions of Nephron Structures
Peritubular Capillaries
transport reabsorbed materials from the PCT and DCT into kidney veins and eventually back into the general circulation
help complete the conservation process (reabsorption) that takes place in the kidney
Unit 1 - Objective 4

29. Aldosterone Hormone secreted from the adrenal cortex
Stimulates kidneys
Retain sodium
Retain water
Secrete potassium
Increase blood volume and blood pressure
Aldosterone is a hormone secreted from the cortex of the adrenal gland. Aldosterone stimulates the kidneys to retain sodium, which in turn will cause the body to retain water. When aldosterone stimulates the kidneys to retain sodium it will also cause the kidneys to secrete potassium.

30. Antidiuretic Hormone ADH
Collecting Duct
ADH- CD permeable to water
H2O
Antidiuretic hormone is produced by the hypothalamus of the brain. *ADH works on collecting ducts of kidney nephrons. ADH will cause the pores of the collecting duct to dilate and thus allow water to move faster. *Water will leave the collecting duct because the interstitial fluid around the collecting duct is hypertonic. ADH prevents the body from losing too much water.
Reabsorb water
Increase blood volume
Increase blood pressure
Urine

31. Dialysis Therapy
Dialysis is a process that artificially removes metabolic wastes from the blood in order to compensate for kidney (renal) failure. Kidney failure results in the rapid accumulation of nitrogen waste (urea, etc.) which leads to azotemia. Uremia and ion disturbances can also occur. This condition can cause acidosis, labored breathing, convulsions, coma and death.
Unit 1 - Objective 11

32. Dialysis Therapy
The most common form of dialysis is hemodialysis which uses a machine to transfer patient’s blood through a semipermeable tube that is permeable only to selected substances. The dialysis machine contains an appropriate dialysis fluid that produces a diffusion gradient. This gradient allows abnormal substances to diffuse from the patient’s blood and produce a “cleaning” effect.
Unit 1 - Objective 11

33. Dialysis Therapy Some key aspects of hemodialysis are:
- blood is typically transferred from an arm artery
- after dialysis, blood is typically returned to an arm vein
- to prevent clotting, blood is typically heparinized
- dialysis sessions occur about three times a week
- each dialysis session can last four to eight hours!
- long term dialysis can lead to thrombosis (fixed blood clots),
infection and death of tissue around a shunt (the blood access
site in the arm)
Unit 1 - Objective 11