Question

1. Trace the pathway of urine formation from the nephron/collecting duct until urine leaves the body through the urethra. Be sure to include all structures urine passes before it exits at the external urethral orifice. Note the differences in the male and female urethra.
2. Draw and label the parts of the uriniferous tubule. Include all parts of the nephron and the collecting duct. List the sequence of filtrate moving through the nephron to collecting duct in the correct sequence.

Answer 1

Pathway of urine formation.

From glomerulus, urine passes to the Capsular space. From capsular space into the proximal convoluted tubule. From proximal convoluted tubule, the urine enters the descending loop of Henle from there to ascending loop of Henle, distal convoluted tubule and collecting duct.

From the collecting duct, urine enters the renal papilla and from there to the minor calyx and major calyx. From there urine reaches renal pelvis and ureteropelvic junction. and urine then enters the ureterovesical junction then to the bladder and finally reaches the urethra to eliminate. In the female, it is 4cm long and urine continued from urethra-out.In male urethra is 20cm long and made up of three parts. Continued from urethra-prostatic urethra-membranous urethra-penile urethra- then pass the urine out.

Parts of the uriniferous tubule

The sequence of filtrate moving through the nephron to collecting duct

The nephron is the functional unit of the kidney which is located in the medullary pyramid. Nephron contains renal corpuscles that have two parts Glomerulus and Bowmanscapusule which contain renal tubules,

The sequence of filtrate moving through the nephron to collecting duct as follows

Kidney-renal corpuscles-afferent arteriole-Bowmanscapsule-glomerulus then into the proximal convoluted tubule then to the descending loop of Henle which is a thin segment and then to the ascending loop of Henle then to the distal convoluted tubule. From there to collecting ducts