Watch Free Classes

Plants and animals create toxic compounds that are produced as a result of metabolic processes and must be eliminated from the body. It contains urea, uric acid, ammonia, carbon dioxide, water, ions, and other substances. Urea, uric acid, and ammonia are the three most major nitrogenous wastes that should be eliminated from the body. Ammonia is the most poisonous of them. Ammonotelic animals are those that excrete ammonia as nitrogenous waste, such as most bony fishes and aquatic amphibians. Ammonia is excreted by diffusion. Ureotelic organisms are those that excrete urea as nitrogenous waste. Ureotelic animals include mammals, amphibians, and reptiles. Uricotelic organisms are those that emit uric acid as nitrogenous waste. 

What is Excretion?

Excretion is the process through which nitrogenous metabolites and other metabolic waste products are removed from the body.

Nitrogenous wastes are largely eliminated from the body through excretory products.

Excretion is defined as the process that aids in the disposal of waste from the body. Homeostasis refers to the maintenance of a steady-state or consistent internal environment. Excretion is critical to sustaining a healthy physique. Uric acid, carbon dioxide, ammonia, urea, water, and ions such as K+, Cl-, Na+, sulphate, phosphate, and others are accumulated by animals through metabolic processes or other ways such as excessive intake.

Excretory Organs in Animals

  1. Contractile vacuoles in freshwater protozoans are used for excretion and osmoregulation.
  2. Renette cells and glands with canals aid in nematode excretion via excretory pores.
  3. Earthworm chloragogen cells are important for excretion.
  4. The kidney (metanephridium) of molluscs is Bojanus’ organ.
  5. Keber’s organ (pericardial gland) is the excretory organ of some mollusks, that is Unio
  6. The proboscis gland is an excretory organ seen in hemichordates such as Balanoglossus.
  7. The excretory structure of Urochordates is the neural gland. Examples are Herdmania and Ascidia.
  8. Branchiostoma has an excretory organ called Hatschek’s nephridium.
  9. Adult kidneys in reptiles, birds, and mammals are called metanephric kidneys (amniotes).

Excretory Products of Animals

  • Ammonia: The first metabolic waste produced by protein metabolism is an amino acid. Animals manage amino acid excess by reducing them to their keto groups. They produce ATP and are involved in catabolism. Ammonia is released from the body of aquatic amphibians in the form of ammonotelic. Ammonia is thought to be the most harmful excretory product.
  • Urea: Urea is the least hazardous type of metabolic waste since it is less soluble in water and only remains in the body for a short time. Terrestrial animals emit urea from their bodies, which is referred to as ureotelic excretion.
  • Uric acid: Because it is insoluble in water and has nontoxic crystals, it tends to stay in the body for a longer period of time.
  • Urine: Urine is a significant excretory product that contains 95 percent water as well as other elements such uric acid, urea, salt, chloride, organic and inorganic potassium. The urine has an acidic pH of 6. The dissociation of haemoglobin results in the formation of urochromes, which cause urine to be pale yellow.

Excretory Products of Plants

Plant excretory products include:

  • Photosynthesis and respiration waste products Through stomata in the leaves and lenticels in the stems, oxygen, carbon dioxide, water, and heat are released into the atmosphere. However, waste products from one process might be used as raw materials in another.
  • Ammonia is produced as a byproduct of protein breakdown. This ammonia is used by plants to synthesise valuable chemicals.
  • Some photosynthetic waste products accumulate in the leaves and bark of trees; plants shed their leaves and bark to free themselves of these wastes.
  • Some waste products continue to accumulate within cells. Raphides, which are calcium oxalate crystals, are examples of such wastes. Raphides are abundant in yam (zimikand).
  • Several plant wastes are beneficial to humans. Such compounds include latex, gums, resins, tannins, sandalwood oil, and eucalyptus oil.

Difference between plant and animal excretion

S.NO

Plant Excretion

Animal Excretion

1

Excretion occurs, but not with specific organs.

Excretion is carried out by a specific organ such as the skin, lungs, or kidneys.

2

Plants emit excretory materials such as water, carbon dioxide, latex, and so on.

Animal excretory materials include ammonia, urea, uric acid, and other nitrogenous wastes.

3

Plant excretory products are employed in the rubber industry, pharmaceutical manufacturing, and so on.

Animal excretory materials, such as cow dung, chicken fecal matter, and so on, are utilised as plant manure.

Conclusion

Plants and animals create toxic compounds that are produced as a result of metabolic processes and must be eliminated from the body. Urea, uric acid, and ammonia are the three most major nitrogenous wastes that should be eliminated from the body. Excretion is the process through which nitrogenous metabolites and other metabolic waste products are removed from the body. Excretion is defined as the process that aids in the disposal of waste from the body. The first metabolic waste produced by protein metabolism is an amino acid. Ammonia is released from the body of aquatic amphibians in the form of ammonotelic. Urea is the least hazardous type of metabolic waste since it is less soluble in water and only remains in the body for a short time.