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
Malphian body - alternative name?
Composed of?
Renal corpuscle
Glomerulus along with Bowman’s capsule
Part of the tubule after the renal corpuscle
Proximal convoluted tubule
A highly coiled network
What comes after the PCT?
Shape?
Conponents?
Henle’s loop
Hairpin shaped
Descending and ascending limb
Which limb of Henle’s loop is continued as what?
Ascending limb
Highly coiled tubular region called DCT
Where do the DCTs open?
What finally happens to many of the structures where the DCT opens
Straight tube called collecting duct, many of which converge and open into the renal pelvis through medullary pyramids in the calyces.
Which structures are situated in the cortex of the kidney?
Malpighian corpuscle
PCT
DCT
Which structure is in the medulla pf the kidney?
The Loop of Henle dips into the medulla
What are cortical nephrons?
In a majority of nephrons, the Loop of Henle is too short and extends only very little into the medulla.
What are juxta medullary nephrons?
In soem nephrons, the Loop of Henle is very long and runs deep into the medulla.
Where doe the efferent arteriole emerge from?
What happens to it?
Glomerulus
Forms a fine capillary network around the renal tubule called the peritubular capillaries
Vasa recta
Formed by?
Shape?
Presence in cortical nephrons?
Minute vessel of the capillary network of the rena tubule that runs parallel to the Henle’s loop
U shaped
Absent or highly reduced
