Joseph P. answered 07/11/19
I just finished my first year of dental school.
Calyces (the plural form of calyx) is where the fluid in the kidney goes to from the medulla. Each Renal pyramid has a calyx. The fluid collects in the kidney and then flows through the calyx to the Renal pelvis. The Renal pelvis connects to all the diff calyces. From there, the fluid flows to the Ureter and to the bladder.
Another way to think of it is like a highway. Many different side streets flow into the highway. The side streets represent the individual medullas/renal pyramids. The entrance to the highway is the calyx and the highway represents the renal pelvis.