Kidney Embryology/Development

Question 1

what layer do the kidneys form from

Answer 1

intermediate mesoderm

Question 2

what nephric structure does the permanent kidney form from

Answer 2

the metanephros

Question 3

when does the metanephros appear and when does it start to function

Answer 3

appear = 5 weeks
function = 9-11 weeks

Question 4

what are the 2 main components that from the metanephros

Answer 4

ureteric bud and the metanephric blastema

Question 5

describe how kidney agenesis can occur

Answer 5

ureteric bud and metanephric blastema don’t communicate/join in embryo, so no kidney forms

Question 6

what defects of the ureteric bud cause kidney agenesis

Answer 6

ureteric bud not long enough to reach metanephric blastema

or there is no ureteric bud

Question 7

what forms the collecting system of the kidney

Answer 7

the ureteric bud

Question 8

what makes up the collecting system of the kidney

Answer 8

ureter, renal pelvis, major/minor calyces, 1-3million collecting ducts

Question 9

what part of the kidney filters the blood and produces urine

Answer 9

the nephrons

Question 10

what are nephrons formed from

Answer 10

the metanephric blastema

Question 11

what are the 4 parts of a nephron

Answer 11

Bowman’s capsule, Proximal convoluted tubule, Loop of Henle, Distal convoluted tubule

Question 12

describe why it is common for varying vasculature of the kidneys in different people

Answer 12

because new blood vessels form as the kidney ascends from the pelvis

Question 13

describe the movement of the kidney in development

Answer 13

it ascends from its origin in the pelvis to level of L1 in weeks 6-9

Question 14

what is the initial blood supply to the kidney

Answer 14

common iliac arteries