Urinary/Renal System

Question 1

3 main functions of urinary/renal system?

Answer 1

Reabsorption, filtration, excretion

Question 2

What are the organs in the urinary/renal system and their functions?

Answer 2

Kidneys- filtration of waste, fluid and electrolyte balance, acid/base balance, regulation of BP and pH, endocrine function

Bladder- store and eliminate waste/urine

Ureter- transport urine from the kidney to bladder

Urethra- expel urine from the bladder

Question 3

Sex differences in urinary system

Answer 3

Female
- shorter
-3 openings
-more prone to utis

Male
-prostate enlargens, putting pressure on urethra causing utis

Question 4

How much blood do the kidneys process?

Answer 4

20% of body’s blood

Question 5

What role do the kidneys have relating to the adrenal glands?

Answer 5

Kidneys control adrenal glands
- kidneys release Renin to regulate fluid and blood pressure
- triggers adrenal cortex to produce adosterone which acts on kidneys to increase sodium and water reabsorption to maintain blood volume and pressure

Question 6

Important roles and functions of renal/urinary system?

Answer 6

-metabolic waste excretion
-endocrine functions
-acid/base buffer system
-controls fluid- conserves or increases fluid & solute
-blood pressure control
-drug metabolism and excretion

Question 7

Role of renal artery and renal veins

Answer 7

Renal artery- brings blood to kidneys
Renal veins- take blood back to heart

Question 8

Urine formation steps (detailed)

Answer 8

1. blood enters into glomerulus via afferent arteriole (filtration happens)
2. filtrate enters proximal convoluted tubule. Rebsorption of sodium, water, ions get reabsorbed into blood via pertibular capillaries (65%)
3. filtrate moving into decending limb of loop of henle
4. filtrate ascends the loop of henle ascending loop then
5. filtrate enter the distal convoluted tubule- selective reabsorption and secretion via pertubular capillaries
6. filtrate passes into collecting tubule > through to collecting duct
7. Final reabsorption happens in collecting duct
8. Urine exits via- collecting ducts, renal papilla, minor calyx, major calyx, renal pelvis, ureter, bladder, urthrea

Question 9

Urine formation steps (shortened)

Answer 9

1. Glomerular filtration- blood enters glomerulus - filtration occurs
2. Tubular reabsorbtion
3. Tubular secretion

• fluid passes into PCT (65% reabsorbed)
  -decends to loop of henle
  -ascends to DCT
  -collecting duct- final reabsorbtion happens (5% is reabsorbed)

Question 10

Function of nephron and what is it composed of?

Answer 10

Fundamental filtering unit of kidney
-filters blood, removes waste and regulates fluid and electrolyte balance to produce urine

• composed of glomerulus and the renal tubule

Question 11

Function of glomerulus and renal tubule?

Answer 11

Glomerulus- filters blood, removing waste and excess fluid, first step in urine formation

Renal Tubule- reabsorbs needed substances back into blood, removes additional waste products and excess substances from filtered fluid > eventually produces urine

Question 12

Where and why does reabsorption happen in urinary system?

Answer 12

Primarily in the proximal convoluted tubule in the nephron
- prevents loss of vital substances- sodium, glucose, water, amino acids
- increases blood volume
- regulates blood pressure
- maintains homeostatisis

Question 13

Where and why does secretion happen in urinary system?

Answer 13

Occurs from the pertibular capillaries into the proximal convuluted tubule and distal convoluted tubule
- secretes excess ions, creatinine, drugs/toxins, urea
- removes substances from blood into the renal tubules that were not filtered at the glomerulus

Question 14

Formation of urea

Answer 14

• muscles break down proteins =producing amino acids + waste nitrogen
• nitrogen is released as ammonia in liver (toxic)
• urea cycle converts ammonia + CO2 into urea
• urea travels through blood to kidneys and excreted

Question 15

Where do the following occur?
-urine concentration
-BP regulation
-pH regulation

Answer 15

Urine concentration = Renal medulla
BP regulation = Juxtaglomuler apparatus
pH regulation = Distal convoluted Tubules

Question 16

What is micturation?

Answer 16

Passing of urine

Question 17

Micturation reflex steps (detailed)

Answer 17

1. Bladder fills with urine > stretch receptors in bladder wall detect increasing tension
2. Sensory afferent impulses travel from bladder to spinal cord, and brain
3. Pons coordinates the response
4. Pons sends parasympathetic motor fibers to contract detrusor muslce, and relax internal sphincter (involuntary)
5. Cerebral cortex sends somatic nerve fibers to external sphincter to relax, when appropriate to expel urine (voluntary control)
6. Urine is passed via urethra

Question 18

Micturation Reflex steps (shortened)

Answer 18

• Bladder fills
  -Stretch receptors send signal to spinal cord + brain (pons + cerebral cortex)
  Pons sends parasympathetic signal to
• Detrusor muscle to contract
• Internal sphincter to relax
  Cerebral Cortex sends somatic motor fibers to relax external sphincter, when approproate (voluntary)

Question 19

Changes in aging to renal system

Answer 19

• nephrons decrease- decreased filtration- excretion/reabsorbtion function of renal tubules
  -glomerular filtration decreases- decreased drug clearance
  -urea increases in blood
• sodium decreases
• bladder muscles weaken > decreased ability to empty bladder
• stress incontinence increases in females
• prostate enlarges- increases frequency

Question 20

How does diabetes affect kidneys?

Answer 20

Prolonged high blood sugar
- damages nephrons
- nephrons less effecient at filtering waste- protein ends up in urine
- waste accumulates in body
-increased utis due to bacteria growing rapidly with sugar in urine

High blood pressure
-damages glomeruli
-damages blood vessels (increases BP)
-leads to kidney failure
- fluid doesn’t get removed which puts pressure on the heart

Question 21

Causes and symptoms of Chronic Kidney Disease

Answer 21

Causes
-Diabetes
-High BP
-Heart problems/stroke
-Obesity
-Family history
-Tobacco use
-60 yrs +

Symptoms
- early signs- blood tests +abnormal urine
- burning or abnormal discharge during urination
- frequency change
- foamy, bloody, brown urine
- hypertension
- swelling in hands and feet
- vomitting, nausea

Question 22

UTIs
Who is high risk, bacteria responsible, treatment

Answer 22

High risk
- diabetes due to high blood sugar in urine
- women
- anyone with disorder that supresses immune system

Bacteria = E.coli

Treatment- antibiotics for symptomatic and no treatment for asyptomatic bacteriuria- to prevent resistance against antibitoics

Question 23

What is diabetes?

Answer 23

The body fails to produce or properly utilize insulin, to stablize blood glucose levels
High blood sugar is most common cause of CKD and kidney failure

Question 24

Urine dip stick - what does it test and indicate

Answer 24

Leukocyctes
-kidney infection, UTI

Nitrite
- UTI

Urobilinogen
-liver cell damage

Protein
- kidney disease

pH
-acidic urine can be caused by kidney disease

Blood
- infection, disease in kidney and bladder

Specfic gravity
- gives info on kidneys ability to concentrate urine in relation to plasma

Ketones
- associated with diabetes, low carb diets, starvation

Bilirubin
- liver damage

Glucose
- diabetes

Question 25

Causes and symptoms of Chronic Kidney Disease

Answer 25

Causes -Diabetes -High BP -Heart problems/stroke -Obesity -Family history -Tobacco use -60 yrs + Symptoms - early signs- blood tests +abnormal urine - burning or abnormal discharge during urination - frequency change - foamy, bloody, brown urine - hypertension - swelling in hands and feet - vomitting, nausea