Difference Between Ammonotelic Ureotelic and Uricotelic

The key difference between ammonotelic ureotelic and uricotelic is that ammonotelic organisms excrete highly toxic and soluble ammonia while ureotelic organisms excrete less toxic urea and uricotelic organisms excrete un-soluble and less toxic uric acid.

Animals excrete different types of nitrogenous wastes. Generally, the type of nitrogenous waste reflects the phylogeny and the habitat of the organism. Moreover, the type of waste and the quantity highly affect the water balance of the organism. Nitrogenous wastes are mainly generated due to the breakdown of proteins and nucleic acids. Ammonia, urea and uric acid are three main types of nitrogenous wastes commonly seen. Therefore, based on the type of nitrogenous waste an animal excretes, there are three groups of animals namely ammonotelic, ureotelic and uricotelic. Ammonotelic organisms excrete ammonia while ureotelic organisms excrete urea and uricotelic organisms excrete uric acid. In addition, uric acid is the least toxic and the least soluble among the three.

CONTENTS

1. Overview and Key Difference
2. What is Ammonotelic 
3. What is Ureotelic
4. What is Uricotelic
5. Similarities Between Ammonotelic Ureotelic and Uricotelic
6. Side by Side Comparison – Ammonotelic vs Ureotelic vs Uricotelic in Tabular Form
7. Summary

What is Ammonotelic?

Ammonotelic organisms are the organisms that excrete nitrogenous wastes in the form of ammonia. Most aquatic animals generally excrete ammonia. Ammonia is a highly toxic product. It also requires sufficient water to excrete. Therefore, aquatic organisms, including most fish species, protozoans, crustaceans, platyhelminths are ammonotelic.

What is Ureotelic?

Ureotelic organisms are the organisms that excrete nitrogenous waste in the form of urea. All terrestrial species mainly produce urea.

Urea is less toxic. It also needs less water, unlike ammonia excretion. Cartilaginous fish, few bony fishes, adult amphibians and mammals including humans, are ureotelic animals.

What is Uricotelic?

Uricotelic organisms are the organisms that excrete nitrogenous waste in the form of uric acid. Among the three modes of nitrogenous waste excretion, uric acid excretion is the most efficient and least toxic mode. Uric acid can be stored in cells and body tissues without any toxic effect and harm. Moreover, uric acid excretion needs very little water compared to the other two modes.

Most snakes and lizards, as well as birds, excrete uric acid. Furthermore, terrestrial arthropods including insects, produce uric acid. Uric acid excretion helps them to conserve water when they live in arid areas.

What are the Similarities Between Ammonotelic Ureotelic and Uricotelic?

• Ammonotelic, ureotelic and uricotelic are three groups of animals based on the type of nitrogenous waste they excrete.
• Three groups basically explain their habitat through the type of nitrogenous waste.
• Moreover, their phylogeny is also reflected in the type of nitrogenous they excrete.

What is the Difference Between Ammonotelic Ureotelic and Uricotelic?

Ammonotelic organisms are organisms that excrete ammonia while ureotelic organisms are the organisms that excrete urea. Meanwhile, uricotelic organisms are the organisms that excrete uric acid. So, this is the key difference between ammonotelic ureotelic and uricotelic. Ammonia is highly toxic for cells and body tissues, but urea is less toxic, and uric acid is least toxic. Moreover, ammonia excretion needs sufficient water while urea excretion needs less water. Uric acid excretion needs very less water compared to the other two methods.

Below infographic summarizes the difference between ammonotelic ureotelic and uricotelic.

Summary – Ammonotelic Ureotelic vs Uricotelic

Metabolism produces different types of waste products. Digestion and catabolism of proteins and nucleic acids mainly result in nitrogenous waste. According to the type of nitrogenous waste animals excrete, there are three groups of animals as ammonotelic, ureotelic and uricotelic. Organisms that primarily excrete ammonia are called ammonotelic while organisms that excrete urea are called ureotelic. And, those that excrete uric acid are called uricotelic. So, this is the key difference between ammonotelic ureotelic and uricotelic.

Reference:

1. “Nitrogenous Wastes.” Lumen, Available here.
2. “Metabolic Waste.” Wikipedia, Wikimedia Foundation, 29 Oct. 2019, Available here.

Image Courtesy:

1. “Ammonia-2D” By Radio89 – Own work (CC BY-SA 3.0) via Commons Wikimedia
2. “Urea-2D” (Public Domain) via Commons Wikimedia
3. “Uric Acid”  By ZooFari – Own work (Public Domain) via Commons Wikimedia