L23: Renal System I

Question 1

kidneys process blood by

Answer 1

removing substances from it and in a few cases adding substances to it

Question 2

major renal functions

Answer 2

regulation of the volume, osmolarity, mineral composition, acidity of the body by excreting water and inorganic electrolytes in amounts adequate to achieve homeostasis

Question 3

second renal function

Answer 3

excretion of waste products (urea, uric acid, creatinine, hemoglobin waste products)

Question 4

urea is a waste product of

Answer 4

proteins

Question 5

uric acid is a waste product of

Answer 5

nucleic acids

Question 6

creatinine is a waste product of

Answer 6

muscle creatinine

Question 7

third renal function

Answer 7

removal of foreign chemicals

Question 8

fourth renal function

Answer 8

gluconeogenesis (synthesis of glucose from amino acids and other precursors)

Question 9

fifth renal function

Answer 9

production of hormones and enzymes

Question 10

what enzymes/hormones do kidney produce?

Answer 10

erythropoietin (erythrocyte production)
renin (blood pressure, sodium balance)
1,25-dihydroxyvitamin D (calcium balance)

Question 11

kidneys location

Answer 11

abdominal (peritoneal) cavity in the posterior abdominal wall

Question 12

ureters

Answer 12

transport urine from kidneys to the bladder

Question 13

the bladder

Answer 13

stores urine until voided from body

Question 14

urethra

Answer 14

carries urine from bladder to the outside of the body

Question 15

two major regions of kidneys

Answer 15

inner renal medulla and outer renal cortex

Question 16

the site of ultrafiltration

Answer 16

outer renal cortex

Question 17

kidneys receive ___% of the cardiac output

Answer 17

20-25%

Question 18

kidneys constitute __% of the total body weight

Answer 18

0.4%

Question 19

___ is critical to renal function

Answer 19

high rate of blood flow

Question 20

renal arteries

Answer 20

branch off the abdominal aorta, supply blood to the kidneys

Question 21

renal veins

Answer 21

carry blood from the kidneys to the inferior vena cava

Question 22

each kidney has over __ million nephrons

Answer 22

1 million

Question 23

the basic structural & functional unit of the kidney

Answer 23

nephron

Question 24

two types of nephrons

Answer 24

cortical and juxtamedullary

Question 25

cortical nephrons

Answer 25

most nephrons (80-85%), have short loop of Henle

Question 26

juxtamedullary nephrons

Answer 26

15% of nephrons, have long loop of Henle, maintain osmotic gradient to produce concentrated urine

Question 27

renal corpuscle

Answer 27

filtering unit responsible for the initial step in urine formation, large and charged proteins and formed elements stay in plasma, while some nutrients, electrolytes, water, and waste products go to renal tubules

Question 28

renal corpuscle consists of

Answer 28

tuft of interconnected capillary loops called glomerulus and ballon-like fluid-filled capsule called Bowman’s capsule into which the glomerulus protrudes

Question 29

Bowman’s capsule

Answer 29

receives the filtrate, inflow to renal tubules

Question 30

glomerulus

Answer 30

capillary network for filtration

Question 31

filtration barrier in the renal corpuscle consists of

Answer 31

three layers

Question 32

first inner layer of filtration barrier

Answer 32

capillary endothelium that is perforated by many large fenestrae

Question 33

second layer of filtration barrier

Answer 33

basement membrane, a gel-like acellular meshwork of glycoproteins and proteoglycans, does not allow negatively charged species to pass through

Question 34

third layer of the filtration barrier

Answer 34

podocytes, capsular epithelial cells, extend foot processes into the basement membrane, have nephrin protein that does not allow big substances to pass

Question 35

filtration slits

Answer 35

between adjacent foot processes constitute the path through which the filtrate, once through the capillary endothelial cells and basement membrane, travels to enter Bowman’s space

Question 36

from Bowman’s capsule, filtered fluid flows into

Answer 36

the proximal tubule, which leads into the loop of Henle

Question 37

the tubule is made up of

Answer 37

a single layer of epithelial cells resting on a basement membrane

Question 38

one common feature of epithelial cells in tubules

Answer 38

tight junctions between adjacent cells

Question 39

From Bowman’s capsule to the collecting ducts,

each nephron is ___

Answer 39

separated from one another

Question 40

the separation of nephrons ends when

Answer 40

ducts merge into the renal pelvis

Question 41

renal arteries

Answer 41

branch off the abdominal aorta, supply blood to the kidneys

Question 42

renal veins

Answer 42

carry blood from the kidneys to the inferior vena cava

Question 43

each nephron has

Answer 43

two arterioles and two sets of capillaries

Question 44

blood enters the glomerular capillaries via

Answer 44

afferent arterioles

Question 45

glomerular capillaries form

Answer 45

efferent arterioles

Question 46

efferent arteriole of a cortical nephron subdivides into

Answer 46

a second set of capillaries called the peritubular capillaries which are profusely distributed to the tubule

Question 47

peritibular capillaries

Answer 47

rejoin to form the veins by which blood leaves the kidney

Question 48

efferent arterioles of juxtamedullary nephrons give rise to

Answer 48

long, looping vasa recta

Question 49

vasa recta

Answer 49

peritibular capillaries that dip into the medulla and then go back up to the cortex, forming hairpin loops

Question 50

vasa recta has significance for

Answer 50

the formation of concentrated urine

Question 51

juxtaglomerular apparatus

Answer 51

in all nephrons, this is the final part of the ascending limb of the loop of Henle, when it passes between the afferent and efferent arterioles

Question 52

the proximity of the ascending limb and the arterioles allows

Answer 52

paracrine communication between the two structures, a key feature of kidney autoregulation

Question 53

nephrons consists of

Answer 53

renal corpuscle and tubule

Question 54

renal corpuscle consists of

Answer 54

capillary tuft, called glomerulus, and Bowman capsule that the tuft protrudes into

Question 55

tubule consists of

Answer 55

proximal tubule, loop of Henle, distal convoluted tubule, and collecting duct-system

Question 56

at the end,

Answer 56

in the collecting ducts, multiple tubes join and empty into the renal pelvis, from which urine flows through the ureters into the bladder

Question 57

each glomerulus is supplied by

Answer 57

afferent arteriole

Question 58

___ leaves the glomerulus

Answer 58

efferent arteriole

Question 59

tubules are supplied by

Answer 59

peritubular capillaries