medulla
the renal medulla contains capillaries and urine forming tubules
glomerular,capsules,Convoluted tubules ,kidney loops are the parts of Nephron... Nephron is the basic unit of a kidney.... group of nephrons constitute the kidney.. so you can't see all of them as individuals... I think you may have got your answer... Thanks.
A metanephric kidney is the functional kidney of adult amniotes, that is, the reptiles, birds, and mammals. It occupies a more caudal position in the body cavity and is a much larger, more compact structure containing many tubules. It is drained by a ureter.
The structures that distal tubes flow into are the collecting ducts of the kidneys. The collecting ducts are small tubes through which urine flows into the renal pelvis.
Nephron
Antidiuretic hormone(ADH) reabsorbs water from the collecting tubules of the kidney causing urine to become concentrated.
Tubules are the tubes running through each little (microscopic) nephrons within each kidney that aid in filtering and collecting of the waste products, and then depending on how much water is in the body it either can reabsorb more water or more salt depending on your electrolyte balance. :-D
Renal cortex
because the fluid pressure in the capillaries is higher than that of kidney tubules
Nephrons
Nephrosis
The renal medulla contains collecting ducts.