Human kidney has

In which of the following is the minimum content of urea present?

The correct arrangement of layers of detrusor muscles in the wall of the urinary bladder is . . . . . . .

Given below are two statements:
Statement $I$: At the base of the urinary bladder,there is an inverted triangular area called the trigone.
Statement $II$: Three layers of dartos tunic muscles are present in the wall of the urinary bladder.
In the light of the above two statements,choose the correct option.

Henle's loops are found in those animals which excrete hypertonic urine. One of the following does not have Henle's loop.

The total number of minor calyces in a human kidney is equal to the number of: