25. The Urinary System

Net filtration pressure in most capillary beds favors:

a. Absorption

b. Osmosis

c. Filtration

d. Secretion

The glomerular capillaries differ from other capillary networks in the body because they

a. Have a larger area of anastomosis

b. Are derived from and drain into arterioles

c. Are not made of endothelium

d. Are sites of filtrate formation

More than one choice may apply.

What is the glomerulus?

a. The same as the renal tubule

b. The same as Bowman's capsule

c. The same as the nephron

d. Capillaries

Explain the process and purpose of tubular secretion.

Explain the important differences between blood plasma and glomerular filtrate, and relate the differences to the structure of the filtration membrane.

Filtration at the glomerulus is inversely related to

a. Water reabsorption

b. Capsular hydrostatic pressure

c. Arterial blood pressure

d. Acidity of the urine

More than one choice may apply.

Which of the following is dependent on tubular secretion?

a. Clearing penicillin from the blood

b. Removal of nitrogenous wastes that have been reabsorbed

c. Removal of excess potassium ions from the blood

d. Control of blood pH

Mark the following statements as true or false. If a statement is false, correct it to make a true statement.

d. Filtrate flows from the renal corpuscle to the distal tubule, the nephron loop, the proximal tubule, and into the collecting system.

Describe the structure of the filtration membrane.

Which of the following substances would pass through the filtration membrane to become part of the filtrate under normal circumstances? (Circle all that apply.)

a. Sodium ions

b. Albumin

c. Glucose

d. Erythrocytes

e. Leukocytes

f. Amino acids

g. Urea

Which of the following is false about the GFR?

a. The GFR averages about 120 ml/min

b. The GFR increases when the afferent arteriole dilates

c. The GFR decreases when the efferent arteriole constricts

d. The GFR decreases when the afferent arteriole constricts

Glomerular hydrostatic pressure _____ filtration; colloid osmotic pressure and capsular hydrostatic pressure_____ filtration.

a. Favors; favor

b. Opposes; oppose

c. Favors; oppose

d. Opposes; favor

The route by which substances are reabsorbed by crossing through the cells of the renal tubule and collecting system is known as the:

a. Paracellular route

b. Transcellular route

c. Primary active transport route

d. Facultative route

Predict the effects the following scenarios would have on glomerular filtration:

a. Having excess proteins in the blood, increasing colloid osmotic pressure

Predict the effects the following scenarios would have on glomerular filtration:

b. Having low arterial blood pressure (hypotension)