TAPASYA Answers-7 October

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Q 1- What is Phosphorus cycle? What is the significance?

ANS- The sedimentary biogeochemical cycle that describes the transport of phosphorus through the lithosphere, hydrosphere, and biosphere is known as the phosphorus cycle.

  • Phosphorus is a mineral that is abundant in phosphate rocks and enters the cycle through weathering and erosion.
  • After millions of years, the crustal plates rise from the seafloor, exposing the phosphates.
  • There are four primary processes that make up the global phosphorus cycle:
    • Tectonic uplift and surface weathering of phosphorus-bearing rocks such as apatite.
    • Phosphorus-bearing rocks are weathered by physical erosionchemical weathering, and biological weathering to supply dissolved and particulate phosphorus to soils, lakes, and rivers.
    • Phosphorus is transported to numerous lakes and run-off to the ocean by riverine and subterranean transportation.
    • Particulate phosphorus sedimentation and burial in marine sediments (e.g., phosphorus related with organic matter and oxide/carbonate minerals) (this process can also occur in lakes and rivers).

Steps in Phosphorous cycle(u can write in diagram form)

  1. Weathering
  2. Absorption by plants
  3. Absorption by animals
  4. Decomposition

Importance of Phosphorus

  • Phosphorus is an essential ingredient for all living organisms.
  • It’s found in nucleic acids like DNA and the phospholipids that make up the cell membrane.
  • It, too, creates the supporting components of our bones, much like calcium phosphate.
  • Phosphorus is typically a limited nutrient, meaning it is a small nutrient that inhibits growth in both freshwater and aquatic organisms.
  • Many creatures require considerable amounts of phosphorus to develop their shells, bones, and teeth.
  • A rock that contains phosphorus in the form of phosphates is referred to as a natural phosphorus reservoir. Small amounts of these phosphates dissolve in soil solution and are absorbed by plant roots when rocks are placed together.
  • Plants provide phosphorus to herbivores and other animals. Trash and dead organisms decay as a result of bacterial-mediated phosphate release.
  • There is no respiratory release of phosphorus into the atmosphere, unlike the carbon cycle.

Human Impact on the Phosphorus Cycle

  • The phosphorus cycle is greatly influenced by a variety of human activities, such as fertilizer use, artificial eutrophication, and so on.
  • Phosphorus fertilizers raise the phosphorus level in the soil.
  • Overuse of these fertilizers decreases soil fertility and is detrimental to soil microbes.
  • When these are washed into surrounding bodies of water, they pose a threat to aquatic life.
  • The amount of phosphorus washed away in water during the transportation of food from farms to cities promotes eutrophication.
  • Algae grows as a result of this. These either produce algal blooms or die, both of which are harmful to the aquatic ecosystem.


As phosphorus is such a powerful element, it is usually found in conjunction with other elements. For the generation of soluble phosphate from unmixed substances, acid-producing bacteria are required. With phosphorus from the earth flowing into the sea and phosphorus in the sea, the purification of phosphorus in various reservoirs changes over time, resulting in phosphorus poisoning.

Q 2- Biodiversity is an important aspect of Human Life. What are components of Biodiversity? What are recent changes in Biodiversity as a whole?

  • In simple terms, biodiversity is the number and variety of living organisms present in a specific geographical region. It includes various plants, animals and microorganisms, the genes they have and the ecosystems formed by them.
  • It relates to the diversity among living organisms on the earth, including the diversity within and between the species and that within and between the ecosystems they form.


  • The concept of biodiversity is an integral part of many human cultures.
  • Biodiversity plays the following roles:
  • Ecological – The major functions done by species which are important for ecosystem function and human survival are:
  • Capture and store energy
  • Produce and decompose organic materials
  • Help to cycle water and nutrients throughout the ecosystem
  • Fix atmospheric gases and help to regulate the climate

The more diverse an ecosystem, better are the chances for the species to survive through adversities and attacks, and subsequently, is more productive.

  • Economic – It is comprehended as a reservoir of resources to be drawn upon for the manufacture of food, cosmetic products, and pharmaceuticals.Some of the significant economic commodities that man derives from biodiversity are:   Food crops, Livestock, Forests, Fish, Medicinal resources
  • Scientific- The level of biodiversity is a good indicator of the state of the relationships of human beings with other living species.

Based on the three elements of biodiversity, that is, genes, species and ecosystems, biodiversity is considered to be of three types:

  • Genetic diversityIt can be understood as the diversity of genes within a particular species. This diversity ensures that some species can survive disruptions. Thus, genetic diversity gives us beautiful butterflies, roses, corals and fruits in myriad hues, sizes and shapes.
  • Species diversity: It refers to the variety of species within a particular geographical region. Species which are different from one another do not interbreed naturally However, closely associated species can have a lot of similarity in their hereditary characteristics. For example, humans and chimpanzees have about 98.4 percent genes which are the same. Species diversity is measured by species richness, which means the number of different species per unit area in a region, and species evenness equitably, which refers to the relative abundance of individuals of different species in an area.
  • Ecosystem or Community diversity: It refers to the diversity of different biological communities or ecosystems like forests, deserts, lakes, corals etc. In a region or on the earth. As the ecosystem changes, species best adapted to that particular ecosystem becomes predominant. Thus, biodiversity also depends on the nature of the ecosystems.

Recent changes in biodiversity

  • Habitat loss and fragmentation:  The habitat loss and fragmentation have been through changes of land use, in particular, the conversion of natural ecosystems to cropland, development of infrastructure projects like rails and roadways, increasing urbanisation and mining activities.

As per the Living Planet report, there has been about a 30% decline in wetlands in the last 40 years. Besides total loss, the degradation of many habitats by pollution also threatens the survival of many species.

  • Over-exploitation of species: Unsustainable use of ecosystems .Over-hunting or poaching of species, overfishing and overharvesting of plant products can quickly lead to a decline in biodiversity. Many species which got extinct  like Steller’s sea cow, passenger pigeon, were subject to over-exploitation by humans.
  • Introduction of alien species: Plants, animals and microorganisms transported deliberately or unintentionally from an outside geographical region can cause great damage to native species and disrupting various aspects of their food chains and the physical environment. For example, in India Water hyacinth was introduced by the British for beautification. But over time, it has become an invasive species, clogging rivers, lakes and other water bodies, thus not allowing any aquatic life to grow and survive.
  • Environmental pollution: The accumulation of Pollution such phosphorus and nitrogen largely from excess fertilizers running off farmland, harmful chemicals firm urban and suburban runoff, industrial effluents etc. which are discharged into the natural water bodies. For example, oil spill off the port of Ennore in Chennai in 2017. Similarly, plastic pollution causes the death of animals. Also, air pollution from industries and vehicles has resulted in the death of many bird species in urban areas.
  • Global climate change:  Already, changes in the flowering and migration patterns as well as in the distribution of various species have been observed throughout the world. These changes have altered food chains and created mismatches within ecosystems
  • Co-extinctions: When a particular species becomes extinct, the plants and animals associated with it in an obligatory way also come under the danger of becoming extinct. For example, When a host fish species becomes extinct, its unique assemblage of parasites also meets the same fate.
  • Natural causes: Like floods, earthquakes and other natural disasters also cause loss of biodiversity.


Q)What is moonlighting and how is it affecting the companies in India? Is it a punishable offence under the law? 

Definition -Moonlighting is a state where employees work for remuneration with entities other than their employers. 

Effects on companies

  • An employee is required and expected to give his entire working time, effort, and energy to the employer’s interest.
  • Moonlighting turns to daylighting: Side jobs may take away the employee’s productivity.
  • Fear of leakage of confidential information of the primary job.

Provisions in law related to moonlighting

  • Moonlighting is not defined in any of the statutes in India
  • Section 60 of the Factories Act deals with restriction on double employment stating that “No adult worker shall be required or allowed to work in any factory on any day on which he has already been working in any other factory, save in such circumstances as may be prescribed”. However, this enactment is applicable only to employees working in factories.
  • Moonlighting is subject to law of the land. The sphere of employment cannot be extended by the employer beyond working hours and outside his place of employment.
  • The Courts of law in India dealing with employment are Writ Courts and Labour Courts, which exercise jurisdiction based on equity or fairness. Therefore, the Courts may lean in favour of the employee unless the contravention of the employee has led to serious prejudice and loss to the employer.

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