Explain why an athlete, who has just run a marathon on a summers day, would have higher concentration of ADH (anti-diuretic hormone) in their blood.

The athlete is running a marathon, therefore their muscles are constantly contracting and therefore using up ATP (Energy). ATP is generated through respiration in cells in the human body. Respiration generates heat. It is also a summers day suggesting temperatures would be higher. Therefore, the blood temperature of the athlete would rise, meaning a negative feedback response is needed to cool the body down. One way the body cools itself down, is by sweating. Because the body is secreting sweat, it loses water. This makes the internal solute concentration of the blood too high. Therefore, the body needs to preserve more water to maintain its osmotic balance.  The body does this by secreting ADH (anti-diuretic hormone), which makes the plasma membranes of the cells of the collecting duct (in the nephrons in the kidneys) more permeable to water by adding aquaporins (which are water channels) to their membranes. The high solute concentration of the medulla means that most of the water in the collecting duct is reabsorbed by osmosis. Thus, ADH levels in the athlete are high to preserve water in response to a loss in water due to sweat secretion to cool down the body's blood temperature.

AN
Answered by Aryan N. Biology tutor

5832 Views

See similar Biology IB tutors

Related Biology IB answers

All answers ▸

What hormone is involved in the function of the collecting duct in the nephron to retain water?


Describe the different phases involved in mitosis


Discuss the incompleteness of the fossil record and the resulting uncertainties about human evolution.


Outline how crossing over and random orientation promotes genetic variation.


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences