Fill in the blank with the best possible answer.

1		The is the largest organ in the urinary system.
2		The connects the kidney to the urinary bladder.
3		The triangular shaped structures in the kidney are called renal .
4		The calyces are areas that drain directly into the renal pelvis.
5		The muscle in the wall of the bladder is smooth muscle.
6		The portion of the urethra within the penis is called the urethra.
7		The arteries are within the renal columns.
8		The blood vessels are at the border of the cortex and medulla in the kidney.
9		The is the first part of the nephron after the renal corpuscle.
10		The is the functional unit of the kidney.
11		acts on the DCT and collecting duct to help conserve water.
12		The mechanism establishes an osmotic gradient in the renal medulla.
13		The blood vessels surrounding the loop of Henle are called the .
14		causes the DCT to increase in sodium permeability.
15		in the urine is a sign of diabetes.