Osmoregulation

Introduction

Osmoregulation is a very important process that takes place in living organisms to maintain a balance between the water and mineral levels. How can we define osmoregulation?

Osmoregulation is the adjustment of a cell’s or organism’s osmotic pressure in proportion to the surrounding fluid and maintaining a balance between the water and mineral levels despite the changing external environmental conditions. It is the process of controlling water potential within a cell or organism to maintain fluid and electrolyte balance in the environment. 

Let us now take a deeper insight into osmoregulation classification in detail.

Why is the Process of Osmoregulation Important

Life forms constantly interact with their environment, exchanging water and nutrients through food and water consumption as well as excretion in the form of perspiration, urine, and faeces. There is a tendency to amass toxic waste and water when there is no mechanism to regulate osmotic pressure or if a disease impairs this process, which can have fatal effects.

Types of Osmoregulation

There are two major types of osmoregulation, namely, osmoregulators and osmoconformers. Let us know about them in detail:-

1)    Osmoregulators- Osmoregulators are those living organisms that are active in maintaining their osmotic pressure without being dependent on the external environment. Some major examples of osmoregulators are human beings and freshwater fish like Rohu. Freshwater fish can control the concentration level of salt despite the environment they are in. Humans are also osmoregulatory as kidneys actively maintain the osmotic pressure through the process of filtration

2)    Osmoconformers- Marine organisms are osmoconformers that maintain an internal environment that is identical to their external environment. The osmotic pressure of the organism’s cells is equal to the osmotic pressure of its surroundings. Marine invertebrates like jellyfish, scallops and lobsters are examples of osmoconformers. 

Osmoregulation in Organisms

Osmoregulation is found in many living organisms. Let’s have a look at each of them separately:

1) Osmoregulation in human beings 

Kidneys regulate the amount of water in urine discharge and play an important role in human osmoregulation. The human body can raise the permeability of the collecting ducts of the kidney to reabsorb water and prevent it from being expelled by using hormones including antidiuretic hormone and aldosterone. 

The kidneys filter the blood and determine which compounds should be reabsorbed and which should be excreted as waste. This filtration is carried out by tubules, which are tiny tubular structures.

The Bowman’s capsule, the proximal convoluted tubule, the loop of Henle, the distal convoluted tubule, and the collecting duct are the five main sections of the kidney tubules.

2)    Osmoregulation in plants

Plants are neither osmoregulators nor osmoconformers. While higher plants lack distinct osmoregulatory organs, the stomata are critical in regulating water loss through evapotranspiration, and the vacuole is significant in regulating the concentration of solutes in the cytoplasm at the cellular level. 

Strong winds, low humidity, and high temperatures all contribute to increased leaf evapotranspiration. Abscisic acid is a hormone that helps plants conserve water by closing stomata and stimulating root growth, allowing more water to be absorbed.

3)    Osmoregulation in marine animals

 In marine mammals, water balance is maintained through metabolic and dietary water, whereas electrolyte homeostasis may be maintained by accidental ingestion of dietary salt.

4)    Osmoregulation in terrestrial animals

Dehydration and desiccation are risks that all organisms encounter. For vertebrates, a terrestrial environment results in both passive water loss to the air and solute absorption from the diet. Terrestrial environments tend to change the osmotic concentration of vertebrates. 

As a result, land animals have evolved numerous adaptations to combat the drying conditions of terrestrial life. Animals cannot be entirely waterproof; urine, excrement, and sweat exchange breathing all cause them to lose some water. Water from drinking, eating, and cellular respiration replaces this water. 

Conclusion

Biological systems in life forms are constantly in contact with the environment, exchanging water and nutrients through food and water consumption, as well as excretion in the form of sweat, urine, and faeces. 

When there is no mechanism to regulate osmotic pressure or when a disease hinders this process, hazardous waste and water tend to collect. Different organisms have different mechanisms to regulate the loss of water.