Renal-Chapter 26

Question 1

What separates the glomerular and peritubular capillary beds?

Answer 1

Efferent arteriole

Question 2

What does each nephron contain?

Answer 2

• Glomerulus (tuft of capillaries)

- Long tubule where filtered fluid is converted into urine

Question 3

What’s the typical pressure in the glomerulus?

Answer 3

High hydrostatic pressure (60 mmHg)

Question 4

2 types of nephrons

• Where
• Characteristics

Answer 4

Cortical nephrons
close to the surface of the kidney (AKA cortex)
Short LOH

Juxtamedullary nephrons
penetrate deep into medulla
Long LOH

Question 5

Which nephrons surround the peritubular capillary network?

Answer 5

Cortical nephron

Question 6

Which nephrons yield more concentrated urine?

Answer 6

Juxtamedullary

Question 7

Which nephrons are located in the vasa recta

Answer 7

Juxtamedullary

Question 8

Smooth muscle that lines the wall of the bladder

Answer 8

Detrusor muscle

• Has a lot of gap junctions
• Laced with large amounts of elastic tissue

Question 9

Area of bladder that opens into the posterior urthera

Answer 9

Trigone (smooth mucosa)

Question 10

Smooth muscle that prevents emptying of bladder (in the neck)

Answer 10

Internal sphincter

Question 11

Skeletal muscle in bladder

Answer 11

External sphincter

-Under voluntary control

Question 12

Pelvic nerve fibers

Answer 12

Sensory-detect stretch in bladder from increasing frequency of action potentials to sacral region (S1-S3)

Motor-Parasympathetic fibers from spinal cord innervate detrusor muscle to empty bladder

Question 13

Pudendal nerves

Answer 13

Innervate external sphincter (skeletal muscle) under voluntary control.

Question 14

Hypogastric nerves

Answer 14

Sympathetic innervation that stimulates blood vessels

Sensory-senses fullness,pain.

Question 15

T/F Composition of urine changes once it leaves the kidneys

Answer 15

F

Question 16

What happens when calyces are stretched in the kidney?

Answer 16

Increases inherent pacemaker activity

Initiates peristaltic contractions that spread along length of ureter

Question 17

Ureter innervation

Answer 17

Smooth muscles

• Sympathetic=inhibitory
• Parasympathetic=enhances contractions

Question 18

If there’s blockage in the ureters what will happen?

Answer 18

Ureterorenal reflex
-Sympathetic reflex to constrict renal arterioles in kidney.

-Decreases urine output

Question 19

T/F Ureters have pain nerve fibers

Answer 19

T

Question 20

Explain the micturition reflex

Answer 20

As bladder fills, receptors are stretched which sends a sensory signal through pelvic nerve to sacral segement (S1-S3) and back to bladder to contract detrusor muscle (parasympathetic)

If bladder does not empty, micturition contracts relax

As bladder fills more, reflexes become more frequent and stronger.

When threshold reached, 2nd reflex causes pudendal nerve to be inhibited (voluntary signal override) and external sphincter is relaxed to pee.

Question 21

Renal blood flow is what percent of cardiac output

Answer 21

20

Question 22

Urinary excretion rate formula

Answer 22

GFR- Reabsorption rate + Secretion rate

Question 23

Reabsorption vs Secretion

Answer 23

Reabsorption
-Substance goes from renal tubules back into blood

Secretion
-Substance from blood stays in renal tubules