kidney anatomy and function (midterm 3)

Question 1

what do the kidneys do

Answer 1

act to rid the body of waste and control the volume and composition of bodily fluids

Question 2

where do substances in kidney come from/go

Answer 2

cleared substances are excreted in the urine, needed substances are returned in the blood

Question 3

where do the kidneys lie in the body

Answer 3

posterior wall of the abdomen outside the peritoneal cavity

Question 4

what does the medial side of the kidneys contain

Answer 4

an indented region (hilum), which allows passage of structure such as
- renal artery
- ureter (carriers urine out of the kidney to the bladder

Question 5

what are the two regions of the kidney

Answer 5

the outer cortex (outside surface)
inner medulla (inside surface)

Question 6

how much of cardiac output is blood flow to the kidneys

Answer 6

21%

Question 7

what is the vascular nomenclature of the kidneys

Answer 7

• Blood enters the kidney through the
  renal artery, then branches to form interlobar arteries,
  arcuate arteries, interlobular arterioles,
  and afferent arterioles
• Afferent arterioles lead to the
  glomerular capillaries, which then
  combine to form efferent arterioles, and
  then the peritubular capillaries

Question 8

what are glomerular capillaries the site of

Answer 8

fluid and solute filtration

Question 9

what do efferent arterioles regulate?

Answer 9

pressure

Question 10

what do peritubular capillaries do

Answer 10

empty into the venous system - these are the site of reabsorption

Question 11

where do peritubular capillaries go into

Answer 11

interlobular vein, arcuate vein, interlobar vein, and renal vein

Question 12

where does rapid filtration come from

Answer 12

high hydrophobic pressure in the glomerular capillaries

Question 13

where does rapid reabsorption come from

Answer 13

low hydrostatic pressure in the peritubular capillaries

Question 14

where does fluid flow in each nephron

Answer 14

fluid flows from the glomerular capillaries into Bowman’s capsule, into the proximal tubule, into the loop of Henle (consists of descending and ascending limb)

Question 15

what do nephrons do

Answer 15

they form urine (each kidney has ~ 1 million)

Question 16

how many ducts form a large duct in nephrons, and what do they become

Answer 16

8 to 10 cortical collecting ducts join to form a larger duct, which runs downward to become the medullary collecting duct and ultimately the collecting duct

Question 17

how many large ducts are in each kidney

Answer 17

~ 250 large collecting ducts, each which collects from ~ 4000 nephons

Question 18

what are the different types of nephrons

Answer 18

cortical nephrons - glomeruli located in outer cortex and possess short loops of Henle

juxtamedullary nephrons - glomeruli located deep in renal cortex and possess long loops of Henle

Question 19

what is micturition

Answer 19

emptying of the bladder

Question 20

what is urinary excretion rate determined by

Answer 20

filtration rate minus reabsorption rate plus secretion rate

Question 21

what does the rate of substance excretion into the urine depend on

Answer 21

glomerular filtration, reabsorption of substances from the renal tubules into the blood, and secretion of substances from the blood into the renal tubules

Question 22

where does urine formation go from/to (the process)

Answer 22

1. filtration from glomerular capillaries -> Bowman’s capsule
2. renal tubules -> peritubular capillaries
3. peritubular capillaries -> renal tubules