Practical 4 - Urinary

Question 1

What are the 3 main functions of the urinary system?

Answer 1

excretion of liquid wastes and exogenous substances (like ammonium and drugs)
regulation of blood pressure, volume, and pH
production of hormones (renin and erythropoietin)

Question 2

What are the 4 main organs of the urinary system?

Answer 2

kidneys, ureters, urinary bladder, and urethra

Question 3

Which kidney is lower, and why?

Answer 3

right is lower because the liver takes up more space

Question 4

How much blood do the kidneys filter per day in men and women?

Answer 4

men- 180 L
women - 150 L

Question 5

What are the traits of normal, fresh urine?

Answer 5

yellow to deep amber
clear/transparent in turbidity
aromatic
specific gravity 1.001-1.028
pH 4.5-8.2
1-2 L per 24 hours (1-1.3 ml per min)

Question 6

What is the production rate formula?

Answer 6

urine volume (mL) /
time since last void (mins)

Question 7

What is specific gravity?

Answer 7

density of urine divided by density of distilled water (aka how concentrated the urine is)

Question 8

What is the definition of production rate?

Answer 8

amount or urine being produced per min

Question 9

What are the normal components of urine?

Answer 9

water, ions, urea, uric acid, ammonia, and creatinine

Question 10

What are some abnormal components of urine, and what would the presence of those things be called?

Answer 10

glucose (glucosuria)
proteins (albuminuria)
RBCs or WBCs (hematuria, pyuria)
bacteria (infection)
ketone bodies (ketonuria)
casts/precipitates

Question 11

What are the protective layers of the kidney? What is the acronym?

Answer 11

Renal fascia
Adipose capsule
Renal capsule
(Rotten Fish Always Causes Ridiculous Constipation)

Question 12

What are the three renal regions? Describe each of them.

Answer 12

cortex: outer portion between the capsule and medulla
medulla: the innermost part of the kidney that contains the renal pyramids
sinus: cavity within the kidney which is occupied by the calyces, renal pelvis, renal vessels, and adipose tissue

Question 13

What is a nephron, and what are its three functions?

Answer 13

the functional unit of a kidney
filtration (blood filtered from the glomerulus into the renal corpuscle)
reabsorption (substances move from the nephron tubule back into the bloodstream)
secretion (substances move from the bloodstream into the nephron tube)

Question 14

After flowing through the afferent arteriole, describe the flow through the nephron up until the papillary duct.

Answer 14

-enters the glomerulus and the glomerular capsule
-proximal convoluted tubule
-descending limb of the nephron loop
-ascending limb of the nephron loop
-distal convoluted tubule
-collecting duct
-papillary duct

Question 15

After nephron and reaching the papillary duct, describe the flow through the other renal structures up until excretion from they body.

Answer 15

-papillary duct
-minor calyces
-major calyces
-renal pelvis
-ureters
-bladder
-internal urethral orifice
-internal urethral sphincter
-urethra
-external urethral sphincter
-external urethral orifice
-outside body

Question 16

What are the two types of nephrons? How can you tell them apart visually?

Answer 16

cortical - half in the cortex and half in the medulla, no vasa recta (only peritubular capillaries)
juxtamedullary - most in medulla, vasa recta present that looks like a ladder

Question 17

Describe renal blood flow from renal artery to the glomerulus

Answer 17

• renal artery
• segmental artery
• interlobar artery
• arcuate artery
• cortical radiate artery
• afferent arteriole
  (into the glomerulus)
• efferent arteriole
• peritubluar capillaries / vasa recta

Question 18

Describe renal blood flow from capillaries back to renal vein

Answer 18

• peritubluar capillaries / vasa recta
• cortical radiate vein
• arcuate vein
• interlobar vein
• renal vein

Question 19

What vessel structure is present in the arterial flow that IS NOT in the venous flow?

Answer 19

segmental veins (only in arterial, not venous)

Question 20

What three ways do the ureters move urine?

Answer 20

peristalsis, hydrostatic pressure, and gravity

Question 21

What is the technical name for “peeing”?
What forces urine out of the bladder?

Answer 21

micturition
detrusor muscle contracts and forces urine out

Question 22

How does the urethra function?

Answer 22

internal/external urethral sphincters relax to allow passage of urine (internal is involuntary, while external is voluntary)

Question 23

What are the three regions of the male urethra? What are the roles of the internal and external sphincters in males?

Answer 23

prostatic urethra
membranous urethra
spongy urethra

internal - prevent reflux of semen into the bladder during ejaculation
external - voluntary control over voiding urine

Question 24

How long is the urethra in females and males?

Answer 24

females - 3-4 cm
males - 18 cm

Question 25

What is osmosis?

Answer 25

water movement from an area of low solute concentration to an area of high solute concentration

Question 26

Is water uptake active or passive?

Answer 26

passive

Question 27

What is the difference between absorption and reabsorption?

Answer 27

reabsorption: reabsorbed substances were already in the body and are on their way out, but are absorbed for a second time

Question 28

What is the difference between filtrate/tubular fluid and urine?

Answer 28

filtrate/tubular fluid is being modified urine is the final product

Question 29

What type of tissue is the epithelium of the glomerulus? What is the function?

Answer 29

simple squamous, filtration

Question 30

What type of tissue is the epithelium of the proximal convoluted tubule? What is the function?

Answer 30

simple cuboidal with microvilli, reabsorption and secretion

Question 31

What type of tissue is the epithelium of the nephron loop (thick segments)? What is the function?

Answer 31

simple cuboidal, reabsorption and secretion

Question 32

What type of tissue is the epithelium of the nephron loop (thin segments)? What is the function?

Answer 32

simple squamous, reabsorption and secretion

Question 33

What type of tissue is the epithelium of the distal convoluted tubule, collecting duct, and papillary duct? What is the function?

Answer 33

simple cuboidal, DCT: reabsorption and secretion CD: some reabsorption PD: urine

Question 34

What is the function of the renal corpuscle?

Answer 34

podocytes with pedicles that wrap around the capillary endothelial cells blood plasma is filtered through filtration membrane based on size and molecular charge

Question 35

What is the glomerular filtration rate?

Answer 35

volume of filtrate formed in all renal corpuscles of both kidneys per minute

Question 36

What affects the glomerular filtration rate?

Answer 36

blood pressure in glomerulus (usually maintained by afferent/efferent arteriole diameter, important that it doesn't get too high because this can damage the glomerulus)

Question 37

What should not pass through during glomerular filtration?

Answer 37

large molecules like albumin, and formed elements

Question 38

What is the filtration membrane made up of?

Answer 38

endothelium, basement membrane, and slit membrane (between the pedicels)

Question 39

What is the function of the proximal convoluted tubule?

Answer 39

reabsorption of nutrients, solutes, and water (glucose, amino acids, vitamins, bicarbonate, Na+, K+, Cl-) secretion of H+, nitrogenous wastes, and some drugs

Question 40

What is the function of the loop of Henle?

Answer 40

descending - only permeable to water, filtrate osmolarity increases as water leaves the tubule ascending - permeable to solutes, less to water, filtrate osmolarity decreases as solutes leave the tubule

Question 41

What is the function of the (early) distal convoluted tubule?

Answer 41

small amounts of Na+ and Cl- reabsorbed small amount of water follows filtrate is more dilute than when first filtered (has less substances in it)

Question 42

What is the function of the (late) distal convoluted tubule and collecting duct?

Answer 42

90-95% of water and solutes are reabsorbed secretion of K+ and H+ hormones "fine tune" the water reabsorption based on what the body needs

Question 43

How can hormones influence the function of the late distal tubule and collecting duct?

Answer 43

ADH increases the aquaporins allowing water reabsorption (passive), aldosterone increases Na+ and Cl- reabsorption so that water follows (indirect passive)

Question 44

What is facultative water reabsorption?

Answer 44

water reabsorption that can be directly controlled (such as the response to ADH)

Question 45

What is obligatory water reabsorption?

Answer 45

uncontrolled water movement by osmosis, such as in the PCT or DCT when water flows passively following solutes)

Question 46

Regarding ADH, what is the: site of synthesis the location that secretes it stimulus for release target action type of H2O reabsorption

Answer 46

hypothalamus synthesizes posterior pituitary releases released when there is low blood volume or high blood osmolarity (too much stuff in the blood) target is collecting duct cells inserts aquaporins to the collecting duct cells to increase water reabsorption facultative

Question 47

Regarding aldosterone, what is the: site of synthesis the location that secretes it stimulus for release target action type of H2O reabsorption

Answer 47

zona glomerulosa of the adrenal cortex synthesizes and releases it released when there is low blood volume or high plasma K+ targets DCT and collecting duct cells stimulates an increase in Na+ reabsorption and water follows obligatory

Question 48

How does alcohol affect reabsorption?

Answer 48

alcohol blocks ADH release decrease in facultative water reabsorption increase in excretion of dilute urine dehydration and promotes hangover

Question 49

Study histology!

Answer 49

bladder, ureter, renal tubules, renal corpuscle and glomerulus, filtration barrier, kidney cortex

Question 50

What are the three general layers in all of the urinary histology?

Answer 50

mucosa, muscularis (inner longitudinal and outer circular), and adventitia

Question 51

What is a UTI?

Answer 51

urinary tract infection : an infection in any part of the urinary tract, but most common in the urethra and bladder

Question 52

What is the most common cause of a UTI?

Answer 52

E coli bacteria from the intestines enter the urethra and bladder from the anus

Question 53

How does bacteria cause a UTI (what does it do)?

Answer 53

bacterial colonies cause inflammation urethritis (inflammation of the urethra) cystitis (inflammation of the bladder) pyelitis (inflammation of renal pelvis) pyelonephritis (inflammation the renal nephron)

Question 54

What are the common signs and symptoms of a UTI?

Answer 54

frequent and strong urge to urinate small amounts of urine cloudy urine burning sensation with urination strong smelling urine pelvic pain

Question 55

What are the treatments for a UTI?

Answer 55

antibiotics and hydration

Question 56

What is the prevalence of UTIs?

Answer 56

1/2 women in their lifetime 1/20 men in their lifetime older adults and infants are more vulnerable

Question 57

What are risk factors for a UTI?

Answer 57

female (shorter urethra) sexual activity kidney stones/blockages suppressed immune system (diabetes)

Question 58

How can you prevent a UTI?

Answer 58

drink liquids and stay hydrates drink cranberry juice wipe from to back urinate after sexual activity