Chapter 26/27

Prolonged aldosterone stimulation of the distal convoluted tubule may result in

hypokalemia

Alice has been running a marathon and has only been drinking pure water. Which electrolyte imbalance is she likely to experience?

hyponatremia

One mechanism the kidney uses to raise systemic blood pressure is to

increase secretion of renin by the juxtaglomerular complex.

Which of the following is not a normal constituent of urine?

large proteins

The primary role of the carbonic-acid-bicarbonate buffer system is to

limit pH changes caused by metabolic and fixed acids

The two organs that play an important role in maintaining acid-base balance are the

lungs and kidneys

Which hormone(s) is released by heart muscle in response to excessive chamber volume

natriuretic peptides

The ability to form concentrated urine depends on the functions of the

nephron loop, distal convoluted tubule and the collecting duct.

The mechanism for producing a concentrated urine involves all of the following except

obligatory water reabsorption in the proximal convoluted tubule.

When pure water is consumed

osmolarities of the two fluid compartments fall.

When water is lost, but electrolytes are retained

osmosis moves water from the ICF to the ECF

Water molecules move across cells by

osmosis.

Calcium reabsorption by the kidneys is promoted by the hormone

parathyroid hormone

To reduce brain swelling by pulling water out of brain cells, a substance can be injected intravenously to increase the osmotic pressure of interstitial fluid. Which of the following properties must this substance lack in order to be effective?

permeable to brain plasma membranes

The most dangerous problems with electrolyte balance are caused by an imbalance between gains and losses of

potassium ions

The principal ions in intracellular fluid are magnesium, phosphate and

potassium.

Blood colloid osmotic pressure (BCOP) in the glomerulus is generated by

presence of albumin proteins in blood plasma

Aldosterone

promotes sodium retention in the kidneys.

A patient who has been both vomiting and having diarrhea is losing all of the following except ________ from his body.

protein

The anions in highest concentration in the extracellular fluid are

proteins, bicarbonate, and chloride.

The majority of water is reabsorbed by osmosis in the

proximal convoluted tubule

Which of the following is not a renal response to acidosis?

release of HCl into peritubular capillary fluid

Calculate filtration pressure (FP) in a nephron with a glomerular hydrostatic pressure of 55 mm Hg, a blood colloid osmotic pressure of 25 mm Hg, and a capsular hydrostatic pressure of 15 mm Hg.

FP = 15 mm Hg

The final composition of urine is represented by which of the following statements?

Urine = substances filtered - substances reabsorbed + substances secreted

Which hormone does not play a role in regulating fluid and electrolyte balance?

cortisol

In the process of ________, two substances are moved across a cell membrane in the same direction without directly using cellular energy. One of the substances can be moved against a concentration gradient by this process

cotransport

Reabsorption of filtered glucose from the lumen in the PCT is largely by means of

cotransport

Chloride ion is reabsorbed in the thick ascending limb by

cotransport with Na and K ions

Secretion of hydrogen ion by the PCT is by the process of

countertransport

The ________ test is often used to estimate the glomerular filtration rate

creatinine clearance

Substances that can carry electrical current across cell membranes are called

electrolytes.

Under normal conditions, glomerular filtration depends on three main pressures. From the list below, what are these three main pressures? 1. glomerular hydrostatic pressure 2. capsular hydrostatic pressure 3. capsular colloid osmotic pressure 4. blood colloid osmotic pressure 5. urinary bladder hydrostatic pressure

1, 2, and 4 are correct

Approximately ________ liters of glomerular filtrate enter glomerular capsules each day

180

The renal threshold for glucose is approximately ________ mg/dl.

180

Measurement of the functions of a nephron reveals a glomerular capillary pressure of 69 mm Hg, and a pressure in the capsular space of 15 mm Hg. Assuming that the blood colloid osmotic pressure is 30 mm Hg, and that essentially no plasma proteins are filtered by the glomerulus, what is the net filtration pressure in this case?

24 mm Hg

The typical value of water losses and gains each day is

2500 mL

In an adult female, the body consists of about ________ percent water

50

In a lean adult male, the body consists of about ________ percent water

60

The normal pH range for ECF is

7.35 to 7.45

As the filtrate passes through the renal tubules, approximately what percentage is reabsorbed and returned to the circulation?

99

Basically, what occurs in the countercurrent multiplier process?

A higher sodium concentration is produced in the renal medulla that osmotically draws out water, reducing it within the tubules and the urine.

Which hormone most affects the osmolarity of blood?

ADH

________ promotes water reabsorption at the kidneys and stimulates thirst

ADH

Which of the following formulas will allow you to calculate correctly the net filtration pressure (NFP)? (Hint: CsHP is capsular hydrostatic pressure.)

FP = GHP - (CsHP + BCOP)

If a urine sample is distinctly yellow in color, which of the following will be true?

It will contain large amounts of urobilin.

Which of the following is a not a true statement regarding the countercurrent multiplication system?

Osmotic concentration in the nephron loop decreases as fluid flows toward the bottom of the loop.

The principal cation in intracellular fluid is

Potassium

All of the following are components of ECF except

RBCs.

Damage to the glomerular filtration membrane allowing proteins into the capsular space would result in all of the following except

a decrease in capsular hydrostatic pressure

Excess release of natriuretic peptides would cause

a large volume of dilute urine

A patient excretes a large volume of very dilute urine on a continuing basis. This is may be due to

absence of ADH

A transport mechanism that can move a substance against a concentration gradient by using cellular energy is

active transport

Substances larger than ________ are normally not allowed to pass through the filtration membrane.

albumin

Which hormone plays a central role in determining the rate of sodium reabsorption and potassium secretion?

aldosterone

The amount of potassium excreted by the kidneys is regulated mainly by

aldosterone.

When the pH rises above 7.45, a state of ________ exists

alkalosis

Immediate local responses of the kidney to changes in blood flow to maintain GFR occur via

autoregulation

The principal ions in extracellular fluid are sodium, chloride, and

bicarbonate.

The process of filtration is driven mainly by

blood hydrostatic pressure

A chemical that minimizes changes in the pH of a body fluid by releasing or binding hydrogen ion is called a(n)

buffer.

Exchange between the two main subdivisions of ECF occurs primarily at the

capillaries.

The release of atrial naturetic peptides from the heart will cause the body to

excrete sodium ions and decrease ECF

Homeostatic mechanisms that monitor and adjust the composition of body fluids respond to changes in the ________ fluid.

extracellular

The process of ________ involves a carrier protein that can transport a molecule across the cell membrane down its concentration gradient

facilitated diffusion

When the pH ________, a state of acidosis exists

falls below 7.35

The amount of filtrate produced by the kidneys each minute is called the

glomerular filtration rate

The main force that causes filtration in a nephron is

glomerular hydrostatic pressure

The filtration pressure at the glomerulus is equal to

glomerular hydrostatic pressure - (capsular hydrostatic pressure + blood colloid osmotic pressure)

Sympathetic stimulation of the kidney can do all of the following except

increase the glomerular filtration rate

All of the following would result in an increase in renin release except

increased blood volume.

A drug that inhibits angiotensin converting enzyme (ACE) may lead to all of the following except

increased fluid retention

Antidiuretic hormone

increases the permeability of the collecting ducts to water

Angiotensin II produces a coordinated elevation in the ECF volume by all of the following mechanisms except

increasing PNS activity.

The two major subdivisions of the ECF are the

interstitial fluid and plasma.

The ________ is the plasma concentration at which a specific compound will begin appearing in the urine.

renal threshold

Consuming a meal high in salt will

result in a temporary increase in blood volume

The majority of cotransporters and countertransporters are linked to the reabsorption of what ion?

sodium

Tubular reabsorption involves all of the following except

stem cell movements

Intracellular fluid (ICF) is found only within

the cells of the body

Excess hydrogen ion is eliminated from the body largely by

the kidneys.

When the level of ADH (antidiuretic hormone) decreases,

the osmolarity of the urine decreases

Diuretics are used for all of the following reasons except

to reduce glucose levels

The concentration at which all of the carriers in renal tubules for a given substance are saturated is the

tubular maximum

In clinical estimates, ________ of total body water is in the ICF and ________ in the ECF

two-thirds; one-third

In response to increased levels of aldosterone, the kidneys produce

urine with a lower concentration of sodium ions

A(n) ________ acid is an acid that can leave solution and enter the atmosphere

volatile

Amino acids in solution contain both a negative and positive charge and thus are termed a(n)

zwitterion.