Human Excretory System Flashcards
What does the ES consist of in humans?
A pair of kidneys
A pair of ureters
A urinary bladder
A urethra
Colour of kidneys
Reddish brown
Shape of kidneys
Bean shaped structures
Location of kidneys
Between the levels of the last thoracic and third lumbar vertebrae close to the dorsal inner wall of the abdominal cabity
Dimensions of kidneys
Average weight of a kidney
Each kidney of an adult human measures:
10-12 cm in length
5-7 cm in width
2-3 cm in thickness
120-170g
Hilum:
Location
Function
Towards the centre of the inner CONCAVE surface of the kidney is a notch called hilum, through which ureter, blood vessels and nerves enter
Renal pelvis:
Location
Shape
Projections
Inner to the hilum
Broad funnel shaped space
Projections called calyces
Outer layer of kidney
Tough capsule
How many zones are present inside the kidney?
Name them
Two zones
Outer cortex, inner medulla
Describe medulla
Inner layer
Divided into a few conical masses (medullary pyramids)
Medullary pyramids project into the calyces
Cortex location
The cortex extends in between the medullary pyramids as renal columns called Columns of Bertini
Functional unit of kidney
How many units contained in 1 kidney
Complex tubular structures called nephrons
Nearly one million
How many parts are in a nephron?
Name them
Two
Glomerulus, renal tubule
What kind of structure is the glomerulus?
What is it formed by?
How is blood carried away?
Tuft of capillaries formed by the afferent arteriole - a fine branch of teh renal artery.
Blood from the glomerulus is carred away by an efferent arteriole.
The beginning structure of the renal tubule
Describe the structure
What does it enclose
Bowman’s capsule
double walled cup like structure
Bowman’s capsule encloses glomerulus