The fluid in the nephron will have maximum osmolarity at:
1. Bowman's capsule
2. proximal tubule
3. bottom of the loop of Henle
4. distal tubule

A countercurrent mechanism system is a mechanism that expends energy to create a concentration gradient. This mechanism in human kidneys involves:
1. proximal tubule and distal tubule.
2. loop of Henle and vasa recta.
3. distal tubule and collecting duct.
4. glomerulus and Bowman's capsule.

During concentration of urine, urea diffuses out of and enters respectively into the:

Identify the incorrect statement regarding the micturition reflex:

1. It can be inhibited by higher centers in the brain.

2. It is stimulated by accumulation of urine stretching bladder wall.

3. can be stimulated by irritation of the bladder or urethra.

4. it is coordinated in lumbar spinal cord.

The urinary system in humans is not involved in:

1. gluconeogenesis

2. activation of vitamin D

3. regulation of leukocyte and platelet production

4. regulation of blood volume and, indirectly, blood pressure

The endocrine gland located at the superior pole of kidney is:
1. spleen
2. pancreas
3. adrenal gland
4. testes

10 to 15 distinct conical or triangular structures in the human kidney are seen in renal ______ and are known as renal ____________.

All of the following regarding juxtamedullary nephrons in human kidneys are correct except:

The part of the nephron where both hydrogen and potassium ions are secreted into the tubular fluid is the

The flow rate of filtered fluid through the kidney is:
1. glomerular filtration rate.
2. renal plasma flow.
3. filtration fraction.
4. renal blood flow.