Urinary System

Front 1

describe the "micturition reflex"

Back 1

1. stretch receptors fire

2. signals are sent to Micturition Reflex Center [MRC] in pons to sacral spinal cord

3. parasympathetic impulses [detrusor muscle in bladder contracts, sphincter relaxes]

4. urine expelled

5. neurons of MRC fatigue, detrusor muscle relaxes

Front 2

list the kidney functions

Back 2

1. urine formation [removes wastes & maintains fluid balance]

2. secrete erythropoietin [stimulates RBC formation]

3. regulate blood pressure

4. activate vitamin D

Front 3

identify the gross anatomical features of the kidney

Back 3

renal capsule
renal hilum
renal cortex
renal medulla
renal pyramids
renal papilla
renal calyx [major and minor]
renal column

Front 4

identify the microscopic functional unit of the kidney

Back 4

nephron: cortical & juxtamedullary

see handout!

Front 5

trace the blood supply into and out of the kidney

Back 5

1. aorta
2. renal artery
3. segmental artery
4. lobar artery
5. interlobar artery
6. arcuate artery
7. interlobular artery
8. afferent arteriole
9. glomerulus [capillaries]
10. efferent arteriole
11. peritubular capillaries and vasa recta
12. interlobular vein/arcuate vein
13. arcuate vein
14. interlobar vein
15. renal vein
16. inferior vena cava

Front 6

where does filtration occur?

Back 6

Bowman's capsule

Front 7

where does gas exchange occur?

Back 7

peritubular capillaries

Front 8

trace a drop of urine from its formation in Bowman's capsule to the ureter

Back 8

1. glomerulus
2. Bowman's capsule
3. proximal convoluted tubules
4. descending limb of Loop of Henle
5. ascending limb of Loop of Henle
6. distal convoluted tubule
7. connecting tubule
8. collecting ducts (cortical and medullary)
9. renal papillae
10. renal calyces (minor and major)
11. renal pelvis
12. ureter

Front 9

define the term "renal corpuscle"

Back 9

the initial blood-filtering component of a nephron

Front 10

recognize normal components of urine

Back 10

95% water

5% solutes
-nitrogenous wastes [urea --> comes from proteins;
-uric acid --> comes from nucleic acids
-creatine --> comes from muscular contractions]
-electrolytes

Front 11

recognize abnormal components of urine

Back 11

glucose [diabetes]

bilirubin [liver dysfunction]

ketones [fat metabolism]

blood [hematuria]

leukocytes [infection]

Front 12

list the 3 processes involved in the formation of urine

Back 12

1. glomerular filtration

2. tubular reabsorption

3. tubular secretion

Front 13

define "glomerular filtration"

Back 13

movement of substances from glomerular blood into Bowman's capsule

Front 14

list the 3 sources of pressure contributing to Peff

Back 14

1. GHP [glomerular hydrostatic pressure)

2. GPOP [glomerulus plasma osmostic pressure]

3. CHP [capsular hydrostatic pressure]

Front 15

in which direction does each source of pressure tend to push fluid?

Back 15

GHP -- OUT

GPOP -- IN

CHP -- IN

Front 16

list the factors involved in the control of filtration pressure (and how)

Back 16

1. juxtaglomerular apparatus: contact point between JG cells & the macula densa cells of the distal convoluted tubule [INCREASES glomerular filtration rate]

2. atrail naturiuretic peptide: hormone secreted by atria [INCREASES glomerular filtration rate]

3. neural regulation: sympathetic stimulation constricts afferent arterioles [DECREASES glomerular filtration rate]

Front 17

list and define the 2 mechanisms of osmosis in the kidney... and which predominates

Back 17

obligatory osmosis: not hormonally controlled; happens in proximal convoluted tubule; constitutes 90% of water reabsorption [by laws of physics]

facultative osmosis: hormonally controlled; happens in distal convoluted tubule & collecting tubule; constitutes 10% of water reabsorption [what our kidneys can control]

Front 18

list the mechanisms of action of Antidiuretic hormone (ADH) and Aldosterone

Back 18

ADH and aldosterone both increase water reabsorption!

ADH is produced by the pituitary gland & the tubule water permeability increases [starting in the ascending limb of the loop of Henle] by forming aquaporins [pores that allow water to pass through and leave]

aldosterone is produced in the adrenal cortex & it increases sodium reabsorption, therefore water will follow

Front 19

define "tubular reabsorption"

Back 19

things move from glomerular filtrate to peritubular capillaries

Front 20

define "tubular secretion"

Back 20

things move from the blood of peritubular capillaries into filtrate; rids body of excess