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Anatomy And Physiology 2 > Urinary System > Flashcards

Flashcards in Urinary System Deck (100):
0

What are the functions of the urinary system

Dispose of metabolic waste and excess substances through formation of urine + filters the blood: gets rid of nitrogenous waste ammonia etc. salts glucose vitamins.
Regulate fluid electrolyte balance. Regulate acid-base balance in blood. Produce hormone erythropoietin

1

Describe the structure of the kidney

Located retroperitoneally in perirenal capsul

2

What are the three regions of the kidney

Cortex, medulla and pelvis

3

What is the cortex of the kidney

Outer region. Lightly colored and granular

4

Describe the medulla

Darker, reddish brown. Contains cone shaped renal pyramids that are striated. Composed of parallel bundles of urine collecting tubules. The renal pyramid and surrounding cortical tissue constitutes a lobe

5

Describe the pelvis of the kidney

Flat, funnel shaped tube continuous with ureter and exits out the hilium

6

What are the major calyces

Large branches of the renal pelvis that are subdivided into several minor calyces. Collect urine draining from papilla of each renal pyramid. Empty urine into the renal pelvis

7

How does the urine flow through the pelvis and ureters to the bladder

By peristalsis

8

What are ureters

Tubes connecting the renal pelvis to the bladder. Ureters enter bladder at an oblique angle and when bladder is full shape changes and pinches off ureters to prevent backflow of urine

9

What are the three tissue layers that the wall of the ureter is composed of

It are mucosal layer is transitional epithelium. Middle layer is smooth muscle. Outer layer is fibrous

10

Describe the urinary bladder

Stores urine until a limitation. Stretching of wall makes it thinner and more susceptible to rupture. Stretch receptors trigger contractions. Involuntary sphincter control is urine flow into urethra.

11

Describe the urethra

Tube connecting bladder to outside of body. Typically longer in males but not true and cats.

12

What does the urethra carry in females

Urine

13

What does the urethra carry in males

Urine and semen

14

Describe kidney filtration

Kidneys receive one fourth of aortas blood at any given time. All of body's blood is filtered every five minutes. 25% of blood plasma enters the nephron as filtrate. All but one percent of filtrate is reabsorbed back into the blood by capillories surrounding the nephron that are called peritubular capillaries. Remaining filtrate enters calyces as urine.

15

Describe blood flow to and from kidneys

Aorta ➡️ renal artery➡️afferent arteriole ➡️glomerulus ➡️peritubular capillaries ➡️renal vein ➡️inferior vena cava

16

How is the kidney capillary bed and the regular capillary bed different

This capillary bed is different because it is forced movement not by concentration gradient.

17

What is the renal corpuscle

The glomerulus and the Bowmans capsule

18

What is a nephron

Structural and functional renal unit. Forms urine

19

What does the nephron consist of

Glomerulus
Bowmans capsule
Renal tubule

20

Describe the glomerulus

Capillary bed. Blood enters under high-pressure. Endothelium is fenestrated. Filtration of blood is selective only by size. Filtrate enters the renal tubule after the glomerulus

21

What can pass through the glomerulus

Plasma + dissolved solutes

22

What shouldn't pass through the glomerulus

Proteins, cells. Too large to be re absorbed and will Be thus present in urine

23

Describe the Bowmans capsule

Surrounds glomerulus and is continuous with the renal tubule. Odor parietal layer is simple squamous epithelium. Inner visceral layer consists of podocytes that cling to basement membrane. Filtrate passes through fenestrations between the feet in the capsule

24

Where are the pct and dct located

The cortex

25

Where are the loop of henle and the collecting ducts

Medulla

26

Describe the proximal convoluted tubule

Simple cuboidal epithelium with microvilli brush border. Reabsorbs water and solids from filtrate and returns to blood via peritubular capillaries. Secrete substances into filtrate.

27

Describe the loop of Henle

Loop of the renal tubule that dips into the medulla.

28

What are the two portions of the loop of Henle

The descending limb and the ascending limb

29

Describe the descending limb of the loop of Henle

Proximal part has cells similar to proximal convoluted tubule then becomes narrow and has simple squamous cells freely permeable to water

30

Describe the ascending limb of the loop of henle

Tube widens again epithelium is cuboidal and columnar and inpermeable to water

31

Describe the distal convoluted tubule

Cuboidal cells without microvilli. Not as twisted as proximal convoluted tubule. Functions more in secretion than reabsorption. Empty into collecting ducts.

32

Describe the collecting ducts

Receive filtrate from numerous distal convoluted tubule's. Deliver filtrate to renal pelvis. Composed of two cuboidal cell types. Principal cells maintain water and potassium balance and intercalcated cells maintain acid-base balance and have microvilli

33

Describe the glomerulus capillary bed

Fed by afferent arteriole, drained by efferent arteriole. Produces filtrate

34

Describe the peritubular capillaries

Site of reabsorption and secretes. Site of gas exchange. Merge to form renal vein

35

What are the three major processes in urine formation and adjustment of blood composition

Glomerulus filtration
Tubular reabsorption
Tubular secretion

36

Describe filtration

Occurs at glomerulus, size selective only

37

Describe reabsorption

Tubule➡️peritubular capillaries. Good stuff lost at glomerulus is returned to blood unless in excess. All of glucose and amino acids should be reabsorbed

38

Describe secretion

️peritubular capillaries ➡️ tubules. Bad stuff not filtered in glomerulus transported to tubule for excretion

39

Where should reabsorbed and secreted substances also pass through

Institial space between vessels and nephron. Transport may be passive (diffusion) or active (ATP). Osmotic gradient in medulla affects transport

40

How does urine volume regulation work

Amount of water reabsorbed by dct and collecting ducts is variable.

41

What is urine volume influence by

Influenced by adh and aldersterone. Also influenced by pathologies such as diabetes mellitis

42

What does adh do to the urine

Affects water transport proteins in dct and collecting tubules.

43

What is diabetes insipidus

Pu/pd: caused by inadequate adh release from posteur petuitary (central DI) or non responsive tubule cells (nephrogenic DI)

44

What happen when no ADH is present

Collecting duct is not permeable to water and a large volume of urine is produced

45

What happens when no adh is present

Collecting duct is permeable to water and a small volume of urine is produced

46

What does aldersterone do

Acts on DcT and collecting duct cells. Increases reabsorption of NA+ which causes water to follow if adh is present

47

What is the renal threshold of glucose

Limited amount of glucose can be reabsorbed by pct into blood. Excess remains in filtrate/urine

48

What is BUN

Urea in blood

49

What does high glucose in filtrate cause

Increased water secretion➡️ increased urine volume ➡️ dehydration and pu/pd

50

What is the dogs renal threshold

180mg/dl

51

What is the cats renal threshold

240mg/dl

52

What is urination called

Mucturation and uresis

53

What is normal urine output

1-2 ml/kg/hr.

54

What can urine output show

Can provide info about renal function. Affected by other fluid losses (vomiting) and fluid input (iv).

55

What is the best way to measure urine output

With an indwelling urinary catheter

56

What is the glomerulus filtration rate

Volume of blood filtered by glomerulus and entering Bowmans capsule per unit of time. Affected by blood pressure and blood volume. Want a relatively steady rate of GFR

57

What can high GFR show

Not enough time for all substances to be filtered, secreted and reabsorbed

58

What is low GFR

Too much time for reabsorption, substances that should have been excreted and reabsorbed

59

What can GFR be used to measure

Renal function

60

How do you measure kidney function?

Serum creatinine concentration test
Plasma clearance of substance

61

What is the serum creatinine concentration test

Creatinine is a waste product of muscle cells which travels in blood and is excreted in urine. Amount produced and excreted depends on muscle mass but is relatively constant in an individual. Measure amount of creatinine in urine. If elevated, may indicate renal dysfunction.

62

What is the advantage to the serum creatinine concentration test

Cheap and easy

63

What is the disadvantage to the serum creatinine concentration test

Not really sensitive. GFR needs to be 75% less than normal for a change to be detected.

64

What is the plasma clearance of substance

Inject a substance Into the blood, measure the amount of time it takes for the blood to be cleared of the substance: need to take blood samples at regular intervals. Want to use a substance that is not normally present in the blood and one that will not be reabsorbed into blood or secreted back into tubules or metabolized. Test blood samples for presence of substance

65

What is renal dysfunction

Kidneys are unable to remove waste from blood, nitrogen waste builds up in blood and is measurable.

66

What is azotemia

Abnormally high levels of nitrogen waste in blood but no symptoms in individual

67

What is item is

Abnormally high level of nitrogen waste in blood that now produces symptoms

68

How do you test for renal dysfunction

Measure bun

69

What is prerenal uremia

Kidney fx normally but decreases blood flow to kidneys so they cannot remove waste properly. Due to dehydration etc

70

What is renal uremia

Damage to nephrons due to toxins; acute or chronic

71

What is post renal uremia

Due to blockage after kidney can lead to renal uremia

72

What is dialysis

Diffusion of substances through a semi permeable membrane

73

What is hemodialysis

Blood is removed from animal and filtered into a machine : 4-6hrs

74

What is continuous renal replacement therapy

Similar to hemodialysis but slower; takes 12hrs

75

What is peritoneal dialysis

Fluid introduced into peritoneal cavity then flushed out

76

What is bacterial cystitis

Bladder infection, most common in dogs, usually due to bacteria travelling up from urethra

77

What are the signs of bacterial cystitis in Dogs

Pollakiuria, hematuria, Dysuria, cloudy urine, frequent licking of urethra

78

How do you test for bacterial cystitis in dogs and what is the treatment

Urinalysis and the treatment is antibiotics

79

What can cystitis also be caused by

Stones, tumors or be idiopathic

80

What is feline lower urinary tract disease

Collection of disorders affecting bladder and urethra. Can be caused by presence of uroliths, infection, tumor or can be idiopathic.

81

What are the signs of feline lower urinary tract disease

Stranguria, Dysuria, hematuria, frequent licking, innapropriate urination

82

What is the treatment of flutd

Depends on the cause. UA can help in diagnosis

83

What is urethral obstruction

Most common in male cats due to caudal location of penis. Urethra curves and narrows near penis. Can be fatal in 36-48hrs.

84

What are the signs of urinary obstruction

Anuria, Dysuria, stranguria, hematuria, rigid bladder, innapropriate urination

85

What is the treatment for urethral obstruction

Catheterization, cystotomy to remove calculi, or perineal urethrostomy to widen the urethra

86

What urolithiasis

Formation of uroliths in urinary tract. Symptoms are dependant on location and size. Some animals are asymptomatic. tx involves surgery and dietary changes

87

Why do urolithiasis form

Normally substances in Urine remains dissolved but will precipitate and forms crystals and under certain conditions. Composed mainly of minerals. Removed surgically or using lithotripsy

88

What is urethral duplication

Extra urethras

89

What is uranalysis

Tests to evaluate physical and chemical properties of urine.

90

What are the urine collecting methods

Free catch, catheterization, and cystocentesis

91

How do you do urine specimen processing

Collect in clear container without additives. Ideally analyze sample immediately after collection. Refrigerate up to four hours. Reduces bacteria growth but may cause crystallization. Allow sample to warm to rt before testing.

92

What are the physical properties of urine processing

Color, transparency and specific gravity

93

What is specific gravity

Amount of dissolved solutes in urine

94

What are the chemical properties of urine specimen processing

Use dip stick for color change.

95

What is microscopic urine analysis

Centrifuge sample, examine sediment looking for presence of cells and casts

96

What are casts

Cylindrical aggregation of substances

97

What is crystalluria

Crystals in urine

98

What are struvites

Can be caused by more alkaline ph. Most common crystals in cats and dogs.

99

What is calcium oxalate stones

Can be caused by more acidic ph. Common in cats