What is the correct order of the following structures concerning the flow of urine? 1. Pyramids 2. Minor calyx 3. Renal pelvis 4. Major calyx 5. Collecting tubules 6. Ureters

Options

A. A) 1, 2, 4, 3, 6, 5
B. B) 3, 5, 1, 2, 4, 6
C. C) 5, 1, 2, 4, 3, 6
D. D) 5, 1, 4, 2, 3,6

Explanation

To determine the correct order of the structures concerning the flow of urine, we need to understand the pathway urine takes from its formation in the kidneys to its exit from the body. Here’s a step-by-step breakdown of the flow:

1. **Collecting Tubules**: Urine is first collected in the collecting tubules, which are the final part of the nephron where urine is formed.

2. **Pyramids**: The collecting tubules drain into the renal pyramids. The renal pyramids are cone-shaped tissues in the kidney that contain the collecting ducts.

3. **Minor Calyx**: From the renal pyramids, urine flows into the minor calyx. Each pyramid has a minor calyx that collects urine from the collecting ducts.

4. **Major Calyx**: The minor calyces converge to form major calyces. The major calyx collects urine from several minor calyces.

5. **Renal Pelvis**: The major calyces then drain into the renal pelvis, which is a funnel-shaped structure that collects urine from the major calyces.

6. **Ureters**: Finally, urine flows from the renal pelvis into the ureters, which transport urine to the bladder for storage before excretion.

Putting it all together, the correct order of structures concerning the flow of urine is:
- 5. Collecting Tubules
- 1. Pyramids
- 2. Minor Calyx
- 4. Major Calyx
- 3. Renal Pelvis
- 6. Ureters

Thus, the correct sequence is **5, 1, 2, 4, 3, 6**.