Lecture 41 - Overview of Renal Sys & Micturition

Question 1

[Na+] blood plasma = _____ mM

Answer 1

142

Question 2

[Na+] interstitial fluid = _____ mM

Answer 2

145

Question 3

[Na+] intracellular fluid = _____ mM

Answer 3

15

Question 4

[K+] intracellular fluid = _____ mM

Answer 4

120

Question 5

[Cl-] intracellular fluid = _____ mM

Answer 5

20

Question 6

[Protein] intracellular fluid = _____ mM

Answer 6

4

Question 7

The osmolarity of intracellular fluid is around _____ mOsm

Answer 7

290

Question 8

How does adding pure water change the total water distribution?

Answer 8

Adds to both extracellular fluid and intracellular fluid

Question 9

How does adding isotonic saline change the total water distribution?

Answer 9

Adds to the extracellular fluid, no change in intracellular fluid

Question 10

How does adding salt change the total water distribution?

Answer 10

There is a shift of water from ICF to ECF

Question 11

The _____ is the kidney to bladder

Answer 11

ureter

Question 12

The adult female ureter is around _____ cm long

Answer 12

30

Question 13

Upper sensory innervation of the ureter is from the ______

Answer 13

umbilicus

Question 14

Lower sensory innervation of the ureter is from the _____

Answer 14

vulva or penis

Question 15

In the bladder, the __________ contracts to push urine into the urethra

Answer 15

Detrusor muscle

Question 16

In the bladder, the ________ involuntarily controls the opening and closing of urethra

Answer 16

internal urethral sphincter

Question 17

In the bladder, the ________ in the deep muscles of perineum voluntarily controls opening and closing of urethra

Answer 17

external urethral sphincter

Question 18

The __________ is the primary sphincter and under voluntary control, with extensive __________ innervation

Answer 18

external urethral sphincter; cholinergic

Question 19

In males, the external urethral sphincter has moderate __________ innervation

Answer 19

sympathetic (nor-adrenergic)

Question 20

The bladder holds an average of _____ mL of urine

Answer 20

700-800 mL

Question 21

The adult male urethra is around _____ cm long

Answer 21

20

Question 22

In males, the __________ passes through the prostate gland. Besides urine, it receives secretions containing sperm, sperm motility and viability factors, and substances that neutralize the pH of the urethra.

Answer 22

prostatic urethra

Question 23

In males, the __________ passes through the perineum. It is the shortest segment.

Answer 23

intermediate urethra

Question 24

In males, the __________ passes through the penis. It is the longest segment and receives secretions including mucus and substances that neutralize the pH of the urethra. During ejaculation in the male, the semen passes through all segments of the urethra to the outside.

Answer 24

spongy urethra

Question 25

In males, the __________ is in between the upper internal urethral sphincter and external urethral sphincter

Answer 25

prostatic urethra

Question 26

What are the 3 main differences in the urethras of males vs females?

Answer 26

1. The urethra is 5x longer in males than in females 2. The urethra is divided into three segments in males but is only one short tube in females 3. The urethra is a common duct for the urinary and reproductive systems in males. These two systems are entirely separate in females.

Question 27

The length of a female urethra is around _____ cm

Answer 27

4

Question 28

During filling, the detrusor muscle (smooth muscle) is _______ [inhibited/stimulated] by _______ [parasympathetic/sympathetic] innervation.

Answer 28

inhibited; parasympathetic (causes contraction)

Question 29

During micturition, the detrusor muscle (smooth muscle) is _______ [inhibited/stimulated] by _______ [parasympathetic/sympathetic] innervation.

Answer 29

stimulated; parasympathetic (causes contraction)

Question 30

During filling, the internal urethral sphincter (smooth muscle) is _______ [inhibited/stimulated] by _______ [parasympathetic/sympathetic] innervation.

Answer 30

stimulated; sympathetic (causes contraction)

Question 31

During micturition, the internal urethral sphincter (smooth muscle) is _______ [inhibited/stimulated] by _______ [parasympathetic/sympathetic] innervation.

Answer 31

inhibited; sympathetic (causes contraction)

Question 32

During filling, the external urethral sphincter (**skeletal** muscle) is _______ [inhibited/stimulated] by _______ innervation.

Answer 32

stimulated; somatic motor (causes contraction)

Question 33

During micturition, the external urethral sphincter (**skeletal** muscle) is _______ [inhibited/stimulated] by _______ innervation.

Answer 33

inhibited; somatic motor (causes contraction)

Question 34

Parasympathetic innervation is through _____ nerves to the bladder

Answer 34

pelvic

Question 35

Sympathetic innervation is through _____ nerves in the _________ to the bladder

Answer 35

hypogastric; inferior mesenteric ganglion

Question 36

Somatic innervation is through _____ nerves to the external sphincter

Answer 36

pudendal

Question 37

Spontaneous voiding can be prevented by ___________ [sympathetic/parasympathetic] ganglia which 'blocks' low level afferent input leading to the pons

Answer 37

parasympathetic

Question 38

Spontaneous voiding can be prevented by __________ [activation/inhibition of preganglionic neurons leading to the __________ muscle

Answer 38

inhibition; detrusor

Question 39

Spontaneous voiding can be prevented by __________ [sympathetic/parasympathetic] inhibition of parasympathetic ganglionic transmission leading to the __________ muscle

Answer 39

sympathetic; detrusor

Question 40

Critical threshold

Answer 40

postganglionic parasympathetic neurons activated --> detrusor muscle

Question 41

Stretch receptors for voiding are located in the __________ region

Answer 41

trigone

Question 42

How do pelvic floor muscles contribute to active and passive continence?

Answer 42

increased abdominal pressure, contraction, lifts the bladder, lengthens and compresses the urethra. arranged in 'slings' around urethra.

Question 43

What are the two muscles that make up the pelvic diaphragm?

Answer 43

levator ani and coccygeus

Question 44

Voiding starts with relaxation of __________. Then, the __________ relaxes, leading to contraction of __________. The bladder then has a funnel shape and opening of bladder neck leading to stream.

Answer 44

distal urethral sphincter (DUS); pelvic floor; detrusor

Question 45

The detrusor will normally contract until the bladder is empty. T/F?

Answer 45

True

Question 46

When the bladder is empty, __________ contracts, __________ relaxes, and urine in urethra is moved into __________.

Answer 46

pelvic floor; detrusor; bladder

Question 47

What is neurogenic bladder?

Answer 47

Interruption in innervation of bladder

Question 48

In a neurogenic bladder, a lesion to the upper motor neurons leads to loss of __________ control of voiding. This leads to __________ incontinence.

Answer 48

voluntary, flooding

Question 49

In a neurogenic bladder, a lower motor lesion leads to loss of __________ control of voiding. This leads to __________ incontinence.

Answer 49

voluntary and involuntary; leaking and overflow incontinence. This causes an **increased susceptibility to infection**.

Question 50

What are the 3 layers of the kidney, from out to in?

Answer 50

renal fascia, adipose capsule, renal capsule

Question 51

The kidney receives _____% of cardiac output.

Answer 51

20-25%

Question 52

The kidney represents ____ total body ATP consumption.

Answer 52

1/6

Question 53

The kidney filters ____ L/day of plasma, which is ~60x's blood vol.

Answer 53

180

Question 54

The kidney filters ____ Ibs./day of Na+

Answer 54

1.5

Question 55

The filtration rate (GFR) of the kidney is _____ ml/min at BP 70 mmHg

Answer 55

125

Question 56

Reabsorption of waste products such as _____ is relatively incomplete (~50%), therefore large fractions are excreted.

Answer 56

urea

Question 57

Reabsorption of useful plasma products such as __________ is relatively complete, therefore only small fractions are excreted.

Answer 57

water, NaCl, glucose

Question 58

Functions of the kidney

Answer 58

1. regulation of salt and water balance (regulation of BP) 2. acid/base balance 3. removal of waste products and foreign substances (drugs) 4. secretion of hormones (renin, erythropoietin, 1,25-Vit D3) 5. gluconeogenesis

Question 59

The medullary osmotic concentration gradient in the nephron is _____ to _____ mOsm/L.

Answer 59

300-1400

Question 60

The __________ is at the end of the ascending limb

Answer 60

macula densa. This is involved in regulating blood pressure, electrolyte homeostasis, and body fluid balance

Question 61

The glomerulus is for __________ and the tubule is for __________.

Answer 61

filtration; transport

Question 62

Renal corpuscle flow

Answer 62

First in nephron, includes glomerulus and bowman's space in bowman's capsule

Question 63

Renal tubule flow

Answer 63

1. Proximal convoluted tubule 2. Proximal straight tubule 3. descending limb. of loop of henle 4. thin segment of ascending limb of loop of henle 5. thick segment of ascending limb of loop of henle 6. **distal convoluted tubule** 7. cortical collecting duct 8. medullary collecting duct 9. renal pelvis

Question 64

In the renal corpuscle glomerulus, the nerve supply goes through the __________

Answer 64

afferent arteriole

Question 65

Mesangial cell

Answer 65

contractile cells in the renal corpuscle glomerulus which pack the glomerulus and have features of smooth muscle. Given their contractile properties and the fact that they can control glomerular tone, it is not surprising that they are important in regulating the glomerular filtration rate (GFR)

Question 66

_____ + _____ + _____ = amount excreted in urine

Answer 66

amount filtered + amount reabsorbed + amount secreted

Question 67

Filtration fraction =

Answer 67

GFR/RPF (renal plasma flow)

Question 68

5 criteria for substance W

Answer 68

1. freely filtered 2. not reabsorbed 3. not secreted 4. not synthesized by the tubule 5. not broken down by the tubule

Question 69

If all 5 criteria for substance W are met, then GFR=

Answer 69

GFR=(U * V)/P