MCAT Biology help » biological » solution Biology and Tissue species » Excretory and also Digestive solution » Excretory system » Excretory Regulation instrument
Explanation:

Aldosterone increases the reabsorption of salt from nephron filtrate.

You are watching: Aldosterone directly increases the reabsorption of

The reabsorption of salt leads to reabsorption that water, which renders the urine much more concentrated. Enhancing aldosterone manufacturing would command to boosted blood pressure, since much more water is maintained in the blood stream. 


Explanation:

Antidiuretic hormone, additionally known together vasopressin, increases the reabsorption that water from the collecting duct. It increases the permeability the the collecting duct, which enables water to be reabsorped and also makes the urine much more concentrated.

You have the right to remember what antidiuretic hormone go by remembering the diuetics rise urine production; thus an ANTIdiuretic will decrease pee production.


Which of the complying with would most most likely NOT happen in the excretory system if a person has not drunk water for an extended period of time?


Explanation:

The signal to increase water reabsorption in the nephrons originates from antidiuretic hormones and aldosterone. The to pee volume also decrease in an attempt to retain the fluids already present in the body. Due to the fact that the body is trying to maintain the fluids it has and also there space no incoming fluids, the blood volume must not increase.


Explanation:

Juxtaglomerular cell respond to low levels the sodium and secrete renin in response, which outcomes in the release of aldosterone native the adrenal cortex. Aldosterone, together a result, will boost sodium reabsorption from the collecting duct. This will subsequently increase blood pressure, however, the direct duty of the cells themselves is to control blood osmolarity.


The effect of the hormone vasopressin (ADH) top top the kidney is best described whereby of the following?


Explanation:

Vasopressin acts upon the collecting duct in bespeak to increase its permeability come water. This results in an ext water being reabsorbed, and also increases blood pressure.


Explanation:

In a severely dehydrated patient, the kidneys will be exhilaration to preserve water in the body. Renin is secreted by the kidneys, and also is the beginning enzyme because that a cascade the stimulates the relax of aldosterone. Aldosterone raises the blood press of the body by exhilaration on the distal tubule, and antidiuretic hormone (ADH) is responsible for making the collecting ducts permeable come water, hence concentrating the urine. Because of this, us would suppose that renin levels would be higher than typical in a dehydrated patient.


Report an Error

Example question #2 : Excretory Regulation mechanisms


Which that the complying with is the duty of aldosterone?


Possible Answers:

Water retention


Sodium retention


Sodium and water retention


Sodium and water excretion


Sodium excretion


Correct answer:

Sodium and also water retention


Explanation:

Aldosterone is exit from the adrenal cortex and acts upon nephrons to boost water and also sodium retention. Aldosterone directly affects the synthetic of sodium ion channels and sodium-potassium pump proteins in the nephron, proactively leading to sodium retention and indirectly resulting in water retention based on increased blood osmolarity. Antidiuretic hormone (ADH), top top the other hand, functions by just retaining water without directly affecting salt retention.


Report an Error

Example question #41 : Excretory device


The interaction in between blood pressure and also kidney duty in humans requires coordination by the renin-angiotensin-aldosterone mechanism (RAAS). This system requires the dynamic interplay of the kidneys, lungs, and blood ship to carefully regulate sodium and also water balance.

A normal human kidney has cells surrounding to the glomerulus dubbed juxtaglomerular cells. This cells feeling sodium contents in urine of the distal convoluted tubule, publication renin in response to a short level. Renin is an enzyme the converts angiotensinogen come angiotensin ns (AI). AI is convert to angiotensin II (AII) through angiotensin converting enzyme (ACE) in the lung.

AII stimulates aldosterone cheap in the zona glomerulosa of the adrenal gland. Aldosterone climate acts to upregulate the sodium-potassium pump ~ above the basolateral next of distal tubule epithelial cells to rise sodium reabsorption from the urine, as well as increasing potassium excretion.


A medical professional is evaluating a patience in a dialysis center. She notices the the patient"s blood pressure is high. A usual treatment the high blood press is a class of drugs called ACE inhibitors. After administering one ACE inhibitor, which of the following is most likely to be true?


Possible Answers:

Renin levels will remain elevated


Angiotensin i levels will instantly decrease


Aldosterone levels will continue to be high


Sodium reabsorption in the distal tubule will certainly increase


Renin levels will automatically decrease


Correct answer:

Renin level will stay elevated


Explanation:

The i outlines the role of angiotensin convert enzyme (ACE) in the renin-angiotensin-aldosterone mechanism (RAAS). Due to the fact that ACE inhibitors act on the enzyme the converts angiotensin i to angiotensin II, us would expect renin and also angiotensin ns to continue to be high due to the fact that they room present prior to the ACE action in the RAAS pathway. The hormones existing after ACE action, including angiotensin II and also aldosterone, however would decrease through ACE inactivation, as would sodium reabsorption. The an outcome is normally lower blood pressure.

*

We have the right to see that inhibiting the activity of ACE would reason buildup the renin and angiotensin I, and a to decrease in angiotensin II, i beg your pardon would an outcome in a failure to maintain water.


Report one Error

Example concern #2 : Excretory Regulation mechanisms


What substance is created by the juxtaglomerular apparatus in the kidney to aid regulate blood volume and pressure?


Possible Answers:

Aldosterone


Angiotensin II


Renin


Angiotensinogen


Correct answer:

Renin


Explanation:

The juxtaglomerular device in the distal tubule monitors the filtrate the passes by to sense boosts or decreases in blood volume. Granular cells in the device secrete the enzyme renin, which initiates a cascade that ultimately produces aldosterone. Remember the aldosterone acts on the distal tubule to stimulate sodium reabsorption and also potassium secretion.

Secretion the renin enables the switch of angiotensinogen to angiotensin I. Angiotensin-converting enzyme (ACE) readjust angiotensin ns to angiotensin II in the lungs, which then stimulates the adrenal cortex to release aldosterone and also increase blood volume.

See more: Coolest Homemade Fruit Of The Loom Grape Costume S, Fruit Of The Loom Halloween Costumes


Report one Error

Example concern #9 : Excretory Regulation mechanisms


Carbonic anhydrase is a an extremely important enzyme the is utilized by the body. The enzyme catalyzes the adhering to reaction:

*

A class of drugs the inhibits this enzyme is carbonic anhydrase inhibitors (eg. Acetazolamide, brinzolamide, dorzolamide). This drugs are commonly prescribed in patients with glaucoma, hypertension, heart failure, high altitude sickness and for the therapy of an easy drugs overdose.

In patients through hypertension, carbonic anhydrase inhibitors will protect against the reabsorption of sodium chloride 

*
 in the proximal tubule the the kidney. As soon as sodium is reabsorbed back into the blood, the molecule creates an electric force. This electrical force climate pulls water along with it into the blood. As much more water start the blood, the blood volume increase. By staying clear of the reabsorption the sodium, water reabsorption is reduced and the blood pressure decreases. 

When hill climbing, the atmospheric push is lowered as the altitude increases. As a result of much less oxygen into the lungs, ventilation increases. Indigenous the equation above, hyperventilation will result in more 

*
 being expired. Based upon Le Chatelier’s principle, the reaction will transition to the left. Since there is an ext bicarbonate 보다 protons in the body, the blood will certainly become much more basic (respiratory alkalosis). To avoid such life threaten result, one would certainly take a carbonic anhydrase inhibitor to prevent the reaction from changing to the left.

Carbonic anhydrase inhibitors are beneficial in patients with a medicine overdose the is acidic. The lumen the the collecting tubule is nonpolar. Due to the lumen"s characteristic, molecules that are also nonpolar and also uncharged space able to cross the membrane and re-enter the circulatory system. Due to the fact that carbonic anhydrase inhibitors alkalize the urine, acidic molecules stay in a fee state.


Which that the following side impacts is/are meant in a drug that overstimulates carbonic anhydrase?