Brainscape's Knowledge GenomeTM

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


See full index

Human Structure and Function 2 > 4 (25) The Urinary System > Flashcards

4 (25) The Urinary System Flashcards

1
Q

What are the organs of the urinary system?

A
  • 2 kidneys
  • urinary bladder
  • 2 ureters
  • urethra
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the functions of the kidneys?

A
  • FILTER blood
  • REABSORB water
  • REABSORB needed substances into blood
    (remaining water and waste removed in urine)
    REGULATES
  • blood volume and composition
  • blood pH
  • blood pressure
  • contribute to metabolism
    (calcitriol, erythropoietin, gluconeogenesis)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Where are your kidneys? In relation to the peritoneum?

A
  • between T12 and L3
  • partially protected by 11th/12th rib
  • right kidney lower than left
  • retroperitoneal (kidneys and ureters)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the three layers that surround and protect the kidneys?

A
  • renal capsule
  • adipose capsule
  • renal fascia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Identify the hilum, cortex, medulla, minor and major calyces and the renal pelvis.

A
  • renal hilum => ureter, blood, lymphatic vessels
  • renal cortex => outer layer of kidney
  • renal medulla => area in center (made of renal pyramids, each kidney has 8-18)
  • major calyx => collect urine from minor calyces, empty into renal pelvis
  • minor calyx => drain pyramids as papillae
  • renal pelvis => funnel-shaped tube continuous with ureter
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Trace urine flow.

A

renal pyramid => minor calyx => major calyx => renal pelvis => ureter

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

Does urine change after it leaves the collecting duct?

A

Nope

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

What is the functional unit of the kidney?

A

NEPHRON => number CONSTANT from birth, can function on 2/3 of one kidney, FORMS the urine (2 classes = cortical, juxtamedullary)

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

What are the parts of a nephron?

A 
- RENAL CORPUSCLE
\+ glomerulus
\+ glumerular (Bowman’s) capsule
- RENAL TUBULE
\+ proximal convoluted tubule
\+ nephron loop (loop of Henle)
\+ distal convoluted tubule
\+ collecting duct
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What three processes are used to make urine?

A

1 - glomerular filtration
2 - tubular reabsorption
3 - tubular secretion

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

What process(es) take place in each section?

A

FILTRATION => filtered bad stuff out, good stuff taken back (ONLY in renal corpuscle)
REABSORPTION => picking good stuff back out
SECRETION => tossing bad stuff into waste basket

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

What are the two types of nephrons and how do they differ?

A

CORTICAL => 85% of nephrons; almost entirely in CORTEX
JUXTAMEDULLARY => long nephron LOOPS deeply invade medulla, ascending limbs have THICK and THIN segments, important in production of concentrated urine

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

Why is the structure of the efferent and afferent arterioles so critical to the functioning of the kidney?

A
  • AFFERENT arteriole divides into ball shaped capillary network called the GLOMERULUS (larger than efferent)
  • capillaries rejoin to form EFFERENT arterioles, then peritubular capillaries
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How much kidney do you need to survive?

A

2/3rds of one kidney to survive

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

Describe the vascular system surrounding the nephron.

A
  • blood supplied to the kidneys by renal artery

- VASA RECTA => a series of straight capillaries in the medulla

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

What three structures make up the filtration membrane?

A
  • fenestrated endothelium
  • basement membrane of glomerulus
  • slit membrane (between pedicels)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What does each layer hold back from the filtrate?

A
  • fenestrated endothelium (prevents the passage of cells)
  • basement membrane of glomerulus (prevents passage of large proteins)
  • slit membrane (prevents passage of medium sized proteins)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What type of epithelium is found in the proximal convoluted tubules? What functions occur here?

A
  • CUBOIDAL and they have MICROVILLI

- about 65% of water and 100% of some solutes are reabsorbed here

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

What is the juxtaglomerular apparatus? How does it function to control blood pressure locally and systemically?

A
  • specialized structure formed by the distal convoluted tubule and the glomerular afferent arteriole
  • helps regulate arterial blood pressure and rate of filtration
  • secretes RENIN when blood pressure DECREASES to convert angiotensinogen to angiotensin 1
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How is angiotensin II formed, and how does it increase blood pressure?

A
  • angiotensin 1 is converted to angiotensin 2 in the lungs

- angiotensin 2 is a potent VASOCONSTRICTOR = INCREASES blood pressure

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

What are mesangial cells?

A

hold together afferent arteriole and distal convoluted tube

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

What two types of cells make up the distal convoluted tubules and collecting ducts, and what are the functions of these cells?

A

PRINCIPAL CELLS => respond to antidiuretic hormone (ADH) and aldosterone

INTERCALATED CELLS => secrete H+ (rids body of excess acid)

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

What force drives fluid out of the glomerular capillaries?

A

glomerular hydrostatic pressure

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

What two forces oppose glomerular filtration?

A
  • plasma colloid osmotic pressure

- capsular hydrostatic pressure (in Bowman’s capsule)

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

What is tubular reabsorption?

A
  • the process by which the nephron removes water and solutes from the tubular fluid (pre-urine) and returns them to the circulating blood
  • reabsorption takes place mainly in the PROXIMAL convoluted tubule of the nephron
  • reabsorbs water, glucose, amino acids, urea, and ions (esp. Na+, Cl+, K+)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is reabsorbed in the PCT?

A
  • 65% of water
  • 100% of glucose
  • 100% amino acids
  • 50% urea
  • 65% of potassium
  • 65% chloride
  • 67% of sodium
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

How is sodium moved from the filtrate to the peritubular capillaries?

A

sodium ions are reabsorbed by ACTIVE TRANSPORT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What do we mean by “where sodium goes, water follows”?

A

“the body has a bunch of semi-permeable membranes that only allow some particles to pass through”

  • water follows sodium => OSMOSIS
  • sodium follows water => DIFFUSION
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What do we mean by a transport maximum, and what happens when it is exceeded?

A
  • maximum amount of a substance that can be reabsorbed per unit time (mg/min.)
  • when EXCEEDED => the plasma concentration for a substance at which the transport maximum is exceed and begins to spill into the urine => RENAL THRESHOLD
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

How does ADH affect the DCT and collecting ducts? What does aldosterone do here?

A

ADH => stimulates cells to put water channels (aquaporins) in the membrane (responsible for facultative water reabsorption)

ALDOSTERONE => causes principal cells to synthesize sodium pumps / potassium to be secreted in urine

31
Q

What is tubular secretion, and what are the two main functions of tubular secretion?

A

“the transfer of materials from peritubular capillaries to the renal tubular lumen”

  • secretion of substances to eliminate them from body (ions, nitrogen containing waste (urea, creatinine), and certain drugs)
  • secretion of H+ to maintain blood pH
32
Q

What is meant by “facultative water reabsorption”?

A
  • water withdrawn from the plasma filtrate as a regulated negative feedback control of hydration status under the influence of ADH
  • in the absence of ADH the collecting tubule is impermeable to water and therefore no water is reabsorbed
33
Q

How is a dilute urine produced? A concentrated urine?

A

DILUTE => absence of ADH (tubules absorb more solutes than water) [4x more dilute than plasma]

CONCENTRATED => created by long loops of Henle of juxtamedullary nephrons with a countercurrent mechanism [4x more conc. than plasma]

34
Q

What is meant by the countercurrent mechanism?

A

establishes a concentration gradient in the interstitial fluid of the medulla of the kidney

35
Q

What is diabetes insipidus?

A
  • disorder of salt and water metabolism marked by intense thirst and heavy urination
  • occurs when the body can’t regulate how it handles fluids
  • the condition is caused by a HORMONAL abnormality and NOT related to diabetes
36
Q

Describe the ureters. How do they conduct urine to the bladder? What do we find at the junction of the ureters and the bladder?

A
  • muscosa, muscularis, fibrous coating
  • mucosa is TRANSITIONAL EPITHELIUM
  • mucus protects ureters from urine pH and concentration
  • PERISTALSIS aids in movement of urine (and hyrdostatic pressure, gravity)
  • outer coat (adventitia) contains blood vessels and sensory nerves
  • renal calculi => shock wave lithotripsy
37
Q

Describe the urinary bladder (location, layers, type of epithelium, trigone, internal and external urethral sphincters).

A
  • posterior to pubic symphysis
  • mucosa, submucosa, muscularis (detrusor muscle), serous coat
  • when the bladder is empty, the mucosa has numerous folds called RUGAE
  • rugae and transitional epithelium allow the bladder to expand as it fills
  • TRIGOME => no rugae, between openings of ureters and internal urethral orifice, where mucosa is tightly bound to muscularis
  • internal sphincter = involuntary control
  • external sphincter = voluntary contol
38
Q

How does micturition occur?

A
  • when the bladder is full of urine, stretch receptors in the bladder wall trigger the micturition reflex
  • the internal urethral sphincter relaxes, allowing for urine to pass out of the bladder into the urethra
  • both of these reactions are involuntary
39
Q

How does the urethra differ in the male and the female? How are they the same?

A

MALE => ~20 cm long, seminal vesicle on back of bladder, prostate gland surround urethra, has 3 division: prostatic urethra, membranous urethra, spongy urethra, discharges semen

FEMALE => ~4 cm long, none of that ^^^

BOTH => tube leading from bladder to exterior, has muscularis and mucosa layer of circular smooth muscle, discharge urine

40
Q

How do we evaluate kidney function?

A

Blood Urea Nitrogen (BUN) => urea is a breakdown product of proteins
- influenced by diet (not the best measure of kidney function)

Creatinine => end product of muscle metabolism

  • normally constant
  • can determine creatinine clearance
41
Q

Of BUN and serum creatinine, which one is influenced by diet?

A

BUN

42
Q

What does inulin clearance give us? Clearance of PAH?

A

Clearance of inulin => not absorbed or secreted, how fast it is cleared = GFR

Clearance of PAH (para amino hippuric acid) => not absorbed, actively secreted = good measure of renal plasma flow

43
Q

What does urine normally look like?

A

transparent yellow

lots of water intake = clear

44
Q

What would you expect to find in urine?

A

IONS => Na+, Cl-, K+ & nitrogenous wastes: ammonia, creatinine, urea and uric acid & foreign chemicals: drugs, pesticides, food additives, etc.

SUSPENDED SOLIDS (trace amounts) => bacteria, blood cells, casts

45
Q

What would you NOT find in a normal urine sample?

A
  • albumin
  • glucose
  • acetone (diabetes mellitus)
  • bile (liver disease, obstruction of bile ducts, hemolytic disease)
46
Q

What is a cast?

A

impressions of kidney tubules

47
Q

What is the normal pH of urine? Why?

A

pH = 4.6 - 8

- it is the job of the kidneys to excrete acid into the urine

48
Q

What is the normal specific gravity of urine?

A

1.001 - 1.035

49
Q

What factors would increase the specific gravity of urine? Decrease it?

A

INCREASE

  • damage to the tubules of kidney (a fixed specific gravity) = 1.010
  • diabetes mellitus (“sugar diabetes”) = 1.030
  • emesis or fever = 1.040

DECREASE
- diabetes insipidus (lack of ADH) = 1.003

50
Q

What is the macula densa? What does its cells monitor?

A
  • end of ascending loop of Henle

- Na+, Cl-, and water

51
Q

How does renal autoregulation (myogenic mechanism and tubuloglomerular mechanism) affect the kidneys?

A

myogenic mechanism => vascular smooth muscle contracts when stretched

  • when BP increases, afferent arteriole CONTRACTS
  • when BP decreases, afferent arteriole DILATES

tubuloglomerular mechanism => macula densa cells monitor Na+, Cl-, and water

  • when these substances decrease (low BP), JGA dilates afferent arteriole and INCREASES blood pressure in glomerulus
  • opposite occurs with high blood pressure
52
Q

How does hormonal regulation affect the kidneys?

A
  • vessels in the kidney have sympathetic innervation
  • at rest, efferent/afferent are maximally dilated
  • MODERATE stimulation constricts both EQUALLY
  • STRONG stimulation constricts afferent > efferent, reducing glomerular filtration rate (GFR)
  • ^^^ this triggers release of RENIN
53
Q

How does neural regulation affect the kidneys?

A
  • secretes RENIN when blood pressure DECREASES to convert angiotensinogen to angiotensin 1
  • angiotensin 1 is converted to angiotensin 2 in the LUNGS
  • angiotensin 2 is a potent VASOCONSTRICTOR = INCREASES blood pressure
  • angiotensin 2 stimulates release of ALDOSTERONE and acts on kidney to INCREASE Na+ reabsorption
  • angiotensin 2 stimulates THIRST center of hypothalamus and release of ADH from the posterior pituitary gland
54
Q

What do angiotensin-converting enzyme (ACE) inhibitors do?

A

prevents conversion of angiotensin 1 to angiotensin 2

55
Q

What effect does RENIN have on peritubular capillary pressure?

A

DECREASES by constricting afferent arteriole and increases fluid reabsorption

56
Q

What effect does RENIN have on glomerular mesangial cells?

A

causes them to CONTRACT => reduces total surface area of glomerular capillaries available for filtration, causing more fluid to be retained

57
Q

Making urine is like…

A

…making chicken soup.

58
Q

The only place where filtration takes place is…

A

…the renal corpuscle.

59
Q

The inner layer of the filtration membrane holds back _____ _____ from the blood.

A

formed elements

60
Q

When we think about the proximal convoluted tubule we are thinking about…

A

…tubular reabsorption.

61
Q

When we think about the distal convoluted tubule and collecting duct we are thinking about…

A

…tubular secretion.

62
Q

Which is larger: the afferent arteriole or efferent arteriole?

A

afferent arteriole

63
Q

Urine is changed after it leaves the…

A

…renal papilla.

64
Q

Order the parts of the nephron:

A 
1 renal corpuscle
2 proximal convoluted tubule
3 nephron loop
4 distal convoluted tubule
5 collecting duct
65
Q

The filtration membrane holds back _____ _____ and _____.

A

blood cells

proteins

66
Q

The inner layer of Bowman’s capsule is made up of cells called:

A

podocytes (with fingerlike projections called pedicels)

67
Q

What force promotes filtration?

A

blood hydrostatic pressure (pressure in blood in glomerulus)

68
Q

What forces opposes filtration?

A

blood colloid osmotic pressure

hydrostatic pressure of fluid in Bowman’s space

69
Q

Osmotic pressure is going to be determined by…

A

…the number solute particles.

70
Q

The part of the nephron that is responsible for producing concentrated urine is…

A

…nephron loop.

71
Q

Tubular secretion:

A

rids the body of waste, drugs, H+

72
Q

In order for water to be reabsorbed in the collecting duct…

A

…ADH needs to be present.

73
Q

A concentrated urine is produced due to the concentration of…

A

…sodium in the medulla.

Human Structure and Function 2 (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions