Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

A&P 2 > Chapter 23: Urinary System > Flashcards

Chapter 23: Urinary System Flashcards

1
Q

functions of kidneys

A

-Filter blood
-Regulate blood volume, pressure, and osmolarity
-Regulate electrolytes and acid–base balance
-Secrete erythropoietin, which stimulates the production of red blood cells
-Help regulate calcium levels by participating in calcitriol synthesis
-Clear hormones from blood
-Detoxify free radicals
-In starvation, they synthesize glucose from amino acids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

minor calyx

A

little cup that surrounds the papilla of each pyramid; collects its urine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

major calyx

A

formed by convergence of 2 or 3 minor calyces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

renal pelvis

A

formed by convergence of 2 or 3 major calyces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

each kidney has how many nephrons?

A

1.2 million

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

2 principle parts of nephron

A

-renal corpuscle
-renal tubule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

renal corpuscle

A

filters the blood plasma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

renal tubule

A

-long, coiled tube that converts the filtrate into urine
- duct leading away from the glomerular capsule and ending at the tip of the medullary pyramid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Proximal convoluted tubule (PCT)

A

-arises from glomerular capsule
-Longest and most coiled region
-Simple cuboidal epithelium with prominent microvilli for majority of absorption

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Nephron loop (loop of Henle)

A

U-shaped portion of renal tubule with a descending limb and ascending limb

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

thick segments of nephron loop

A

-have simple cuboidal epithelium
-Initial part of descending limb and part or all of ascending limb are thick; heavily engaged in the active transport of salts and have many mitochondria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

thin segments of nephron loop

A

-simple squamous epithelium
-Forms lower part of descending limb; cells very permeable to water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Distal convoluted tubule (DCT)

A

-begins shortly after the ascending limb reenters the cortex
-Shorter and less coiled than PCT; cuboidal epithelium without microvilli; DCT is the end of the nephron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

collecting duct

A

receives fluid from the DCTs of several nephrons as it passes back into the medulla

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

papillary duct

A

-formed by merger of several collecting ducts
-30 papillary ducts end in the tip of each papilla

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

flow of fluid

A
  1. glomerular capsule
  2. proximal convoluted tubule
  3. nephron loop
  4. distal convoluted tubule
  5. collecting duct
  6. papillary duct
  7. minor calyx
  8. major calyx
  9. renal pelvis
  10. ureter
  11. urinary bladder
  12. urethra
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

stages of urine formation

A
  1. glomerular filtration
  2. tubular reabsorption
  3. tubular secretion
  4. water conservation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Glomerular filtration

A

water and some solutes pass from blood within glomerulus into the capsular space of the nephron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

filtration membrane

A

barrier through which filtered fluid passes; contains three components
- Fenestrated endothelium of the capillary
- The basement membrane
- Filtration slits

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Podocyte foot processes (pedicels)

A

wrap around the capillaries; have negatively charged filtration slits between them

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

molecules smaller than 3 nm that can pass freely through the filtration membrane

A

Water, electrolytes, glucose, fatty acids, amino acids, nitrogenous wastes, and vitamins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Proteinuria (albuminuria)

A

albumin in urine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

hematuria

A

blood in urine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

substances of low molecular weight that are bound to plasma proteins and cannot get through the membrane

A

Most calcium, iron, and thyroid hormone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Blood hydrostatic pressure (BHP)

A

-60 mm Hg
-High in glomerular capillaries because afferent arteriole is larger than efferent arteriole—a large inlet and small outlet

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Hydrostatic pressure in capsular space

A

-18 mm Hg
-Due to high filtration rate and accumulation of fluid in the capsule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Colloid osmotic pressure (COP) of blood

A

32 mm Hg

28
Q

Net filtration pressure (NFP)

A

-10 mm Hg
- balance of BHP,COP, and hydrostatic pressure

29
Q

Glomerular filtration rate (GFR)

A

amount of filtrate formed per minute by the two kidneys combined

30
Q

Filtration coefficient (K )

A

depends on permeability and surface area of filtration barrier

31
Q

Total amount of filtrate produced per day equals

A

50 to 60 times the amount of blood in the body

32
Q

how much urine is excreted per day?

A

1 to 2 L

33
Q

Proximal convoluted tubule (PCT)

A

reabsorbs about 65% of glomerular filtrate; also removes substances from blood and secretes them into tubular fluid for disposal in urine

34
Q

PCT structure

A

-long length
-prominent microvilli
-Abundant mitochondria provide ATP for active transport

35
Q

Tubular reabsorption

A

process of reclaiming water and solutes from tubular fluid and returning them to blood

36
Q

Transcellular route

A

substances pass THROUGH cytoplasm of PCT epithelial cells and out their base

37
Q

Paracellular route

A
  • substances pass BETWEEN PCT cells
  • Junctions between epithelial cells are leaky and allow significant amounts of water to pass through
  • As water passes, it carries a variety of dissolved substances—this is called solvent drag
38
Q

symports on the apical surface

A

-examples of secondary active transport
-they do not directly consume ATP, but are dependent on the primary transport

39
Q

Tubular reabsorption of sodium chloride

A

-Sodium is prevented from accumulating in epithelial cells by pump in the basal surface of epithelium
-pumps out to extracellular fluid and picked up by peritubular capillaries, returned to blood
-the pumps are ATP consuming active transport pumps

40
Q

Tubular reabsorption of other electrolytes

A

-Potassium, magnesium, and phosphate ions diffuse through the paracellular route with water
-Phosphate is also cotransported into the epithelial cells with sodium

41
Q

Calcium is reabsorbed through

A

paracellular (52%) and transcellular (14%) routes, independent of hormones

41
Q

Tubular reabsorption of glucose

A

-glucose cotransported by symports called sodium–glucose transporters (SGLTs)
-Passes through basolateral surface by facilitated diffusion
-Normally all glucose is reabsorbed, none in urine

42
Q

transport maximum

A

maximum rate of reabsorption for a solute, which is reached when all transport proteins are saturated

43
Q

if all transporters are occupied what happens to excess solute?

A

it passes by and appears in urine

44
Q

glycosuria

A
  • glucose in urine
  • classic sign of untreated diabetes mellitus, where plasma glucose may exceed 400 mg/dL
45
Q

what does each solve have?

A

its own transport maximum

46
Q

blood glucose transport maximum

A

220 mg/dL

47
Q

Antidiuretic hormone (ADH)

A
  • stimulates water retention by the kidney (from posterior pituitary)
  • makes collecting duct more permeable to water
  • Dehydration, loss of blood volume, and rising blood osmolarity stimulate arterial baroreceptors and hypothalamic osmoreceptors
48
Q

aldosterone

A
  • steroid hormone that stimulates reabsorption of sodium and secretion of potassium
  • “Salt-retaining hormone”
  • Secreted by the adrenal cortex
  • triggers are: when sodium concentration falls
48
Q

Tubular reabsorption of nitrogenous wastes

A
  • Urea passes through epithelium with water
  • Nephron reabsorbs about half of urea in tubular fluid
  • PCT reabsorbs nearly all uric acid, but later portions of the nephron secrete it
  • Creatinine is not reabsorbed—it is passed in urine
49
Q

how much water in filtrate is reabsorbed in PCT?

A

two-thirds

50
Q

Recycling of urea

A
  • adds to high osmolarity
  • cycled from collecting duct to the nephron loop and back
  • concentrated in the collecting duct and some of it always diffuses out into the medulla
51
Q

countercurrent exchange system

A
  • prevents dilution of the medulla osmolarity gradient
  • formed by blood flowing in opposite directions in adjacent parallel capillaries
  • ensures that salts, urea not also carried away from medulla
52
Q

what does the vasa recta do?

A

carry away water reabsorbed by collecting duct

53
Q

Descending capillaries of vasa recta

A
  • Exchanges water for salt
  • Water diffuses out of capillaries and salt diffuses in
54
Q

Ascending capillaries of vasa recta

A
  • Exchanges salt for water
  • Water diffuses into and NaCl diffuses out of blood
  • Vasa recta gives the salt back and does not subtract from the osmolarity of the medulla
55
Q

specific gravity

A
  • ratio of density of a substance to that of distilled water
  • Density of urine ranges from 1.001 to 1.028 g/mL
56
Q

osmolarity

A

ranges from 50 mOsm/L in a hydrated person to 1,200 mOsm/L in dehydrated person

57
Q

pH of urine

A

ranges from 4.5 to 8.2, usually 6.0 (mildly acidic)

58
Q

chemical composition of urine

A

95% water, 5% solutes

59
Q

abnormal compounds in urine

A

glucose, free hemoglobin, albumin, ketones, bile pigments

60
Q

Diuresis or polyuria

A

output in excess of 2 L/day urine volume

61
Q

Oliguria

A

output of less than 500 mL/da urine volume

62
Q

Anuria

A

0 to 100 mL/day urine volume

63
Q

low urine output

A

less than 400 mL/day, the body cannot maintain a safe, low concentration of waste in the plasma (leads to azotemia)

64
Q

Ureters

A
  • retroperitoneal, muscular tubes that extend from each kidney to the urinary bladder
  • Flap of mucosa at entrance of each ureter acts as a valve into bladder
65
Q

Micturition

A

the act of urinating

A&P 2 (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions