21) The cells lining the proximal convoluted tubule

A) are closely associated with unusual smooth muscle fibers.

B) reabsorb water and reabsorb or secrete sodium, potassium, hydrogen, and bicarbonate ions to determine the final osmotic concentration and volume of the urine.

C) are not permeable to water and solutes.

D) are unusually tall, and their nuclei are clustered together.

E) reabsorb organic nutrients, plasma proteins, and ions from the tubular fluid and release them into the interstitial fluid.

22) The following is a list of the blood vessels that carry blood to the kidney:

1 – afferent arteriole

2 – arcuate artery

3 – interlobar artery

4 – renal artery

5 – glomerulus

6 – interlobular artery

7 – efferent arteriole

8 – peritubular capillary

The proper order in which blood passes through these vessels is

A) 4, 6, 2, 3, 1, 5, 7, 8.

B) 4, 3, 2, 6, 1, 5, 7, 8.

C) 4, 3, 2, 6, 7, 5, 1, 8.

D) 4, 6, 2, 3, 7, 5, 1, 8

E) 4, 3, 6, 2, 1, 5, 7, 8.

23) Following is a list of components of the renal tubule system.

1 – ascending limb of nephron loop

2 – ureter

3 – distal convoluted tubule

4 – descending limb of nephron loop

5 – minor calyx

6 – proximal convoluted tubule

7 – papillary duct

8 – renal pelvis

Choose the correct order of components through which the initial filtrate of urine flows from the renal corpuscle and is conducted to the urethra to be excreted as urine.

A) 4-1-6-3-7-5-8-2

B) 3-4-1-6-5-8-7-2

C) 6-1-4-3-5-7-8-2

D) 3-1-4-6-8-7-5-2

E) 6-4-1-3-7-5-8-2

24) Which of the following will likely occur if glomerular blood pressure falls significantly?

A) Excretion of waste products will increase.

B) Kidney filtration will stop.

C) There will be no effect on pH control.

D) Active secretion will occur normally in the distal convoluted tubule.

E) The renin-angiotensin system is unaffected.

25) In the loop of Henle,

A) active secretion of acids, ammonia, and drugs occurs.

B) ion pumps, which respond to aldosterone, exist.

C) reabsorption of ions, amino acids, water, and other organic nutrients is its primary function.

D) reabsorption of half of the remaining water, as well as two-thirds of the sodium and chloride ions remaining in the tubular fluid, occurs.

E) final adjustments are made in the composition and concentration of the tubular fluid.

26) Reabsorption of glucose occurs mostly in the

A) renal sinus.

B) proximal convoluted tubule.

C) distal convoluted tubule.

D) nephron loop.

E) renal corpuscle.

27) The primary function of the proximal convoluted tubule is

A) filtration.

B) absorption of ions, organic molecules, vitamins, and water.

C) secretion of acids and ammonia.

D) secretion of drugs.

E) adjustment of urine volume.

28) Regulation of the amounts of water, sodium ions, and potassium ions lost in the urine occurs between the nephron loop and the ________.

A) collecting system

B) distal convoluted tubule

C) renal corpuscle

D) proximal convoluted tubule

E) Bowman’s capsule

29) Which process is the vital first step essential to all kidney functions?

A) active secretion

B) reabsorption of nutrients

C) reabsorption of water form the tubular fluid

D) glomerular filtration

E) excretion of metabolic waste products

30) Which is true regarding the general characteristics of normal urine?

A) The bacterial titer is very high.

B) Normal pH range is 2 to 4.5.

C) Normal range of volume is 2500 – 3500 mL/day.

D) Normal urine is typically 65% water content.

E) The osmolarity of normal urine ranges from 855 – 1335 mOsm/L.