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  • 1 answers

Meghna Thapar 6 years, 1 month ago

  • The Oxygen-Cycle:

21% of Oxygen is found in the elemental form in the atmosphere. It also occurs extensively in the combined form in the Earth’s crust as well as also in the air in the form of carbon dioxide. In the crust, it is found as the oxides of most metals and silicon, and also as carbonate, sulphate, nitrate and other minerals. It is an essential component of most biological molecules like carbohydrates, proteins, nucleic acids and fats (or lipids). The oxygen-cycle is the cycle that maintains the levels of oxygen in the atmosphere. Oxygen from the atmosphere is used up in three processes, namely combustion, respiration and in the formation of oxides of nitrogen. Oxygen is returned to the atmosphere by photosynthesis.

  • The Carbon Cycle:

Carbon is an important constituent of organic compounds found in all living beings in the form of carbohydrates, fats, proteins and nucleic acids. Carbon is trapped in the surrounding air and water in the form of carbon dioxide. The consumers devour the organic carbon compounds that producers manufacture. Through respiration, both consumers and producers return carbon to the non-living environment in the form of carbon dioxide. Some carbon accumulates in wood for many years and is eventually returned to the atmosphere by fires or through consumption and respiration by fungi, bacteria and other detrivores. Volcanic eruption also releases carbon dioxide to the atmosphere. Carbon is incorporated into life-forms through the basic process of photosynthesis which is performed in the presence of Sunlight by all life-forms that contain chlorophyll. This process converts carbon dioxide from the atmosphere or dissolved in water into glucose molecules. These glucose molecules are either converted into other substances or used to provide energy for the synthesis of other biologically important molecules. The utilisation of glucose to provide energy to living things involves the process of respiration in which oxygen may or may not be used to convert glucose back into carbon dioxide. This carbon dioxide then goes back into the atmosphere. Another process that adds to the carbon dioxide in the atmosphere is the process of combustion where fuels are burnt to provide energy for various needs like heating, cooking, transportation and industrial processes. Carbon is thus cycled repeatedly through different forms by the various physical and biological activities.

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Dileep Kumar 7 years, 1 month ago

Vaccination is an injection which is injected to an infant to fight against viruses.
  • 2 answers

Aryan Yadav 7 years, 1 month ago

Taxonomy is the biological science which deals with identification nomemclature a d classification of organism The father of taxonomy was Carolous Linnaeous

Sayoni Debnath 7 years, 1 month ago

Taxonomy is the branch of science where organisms are classified by naming and grouping in a hierchial manner based on similarities and dissimilarities. The father of taxonomy is carollaus linnaes
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Aryan Yadav 7 years, 1 month ago

In water,when growth of algae is fast then it take the essential nutrients and all the oxygen dissolved in water which affect the life of aquatic animals(fish,octopus etc.) And they can die. This procees is called eutrophication
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Aryan Yadav 7 years, 1 month ago

It is the process of conversion of atmospheric nitrogen into usable forms such as nitrates,nitrites,amonium acid etc.
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Anashuman Singh 7 years, 1 month ago

Persistance of sound in a big hall due to multiple reflections from the walls, ceilings and floor is termed as reverberation whereas reflection of sound from any distant object which leads to its repeating is termed as echo.
  • 1 answers

Aryan Yadav 7 years, 1 month ago

There is a vast no. Of organisms on the surface of earth and they are different in shape and size. It is not practically possible to study each and every organism seperately. Therefore,we need classification.
  • 2 answers

Aryan Yadav 7 years, 1 month ago

She is right??

Aisha Puri 7 years, 1 month ago

Everything is important .All u need is to study hard?
  • 1 answers

Sayoni Debnath 7 years, 1 month ago

Pteridophyta is a division of the much broader kingdom plantae. Pteridophyta is the highest group of cryptogamae. In such division all plants parts are differentiated and the plant has proper vascular tissues.example is ferns and marsilea
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Sayoni Debnath 7 years, 1 month ago

Galileo galilei
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Ayus Agarwal 7 years, 1 month ago

Soil is the thin layer of material covering the earth's surface and is formed from the weathering of rocks. It is made up mainly of mineral particles, organic materials, air, water and living organisms.
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Sayoni Debnath 7 years, 1 month ago

Smoke is an aerosol whose dispersed medium is gas and dispersed phase is solid. It is a colloid
  • 2 answers

Priyanshu Patel 7 years, 1 month ago

Fair and handsome

Poojan Shewale 7 years, 1 month ago

X men face creem
  • 1 answers

Meghna Thapar 6 years, 1 month ago

AIDS stands for Acquired Immuno Deficiency Syndrome. It is a fatal disease. The disease of AIDS is caused by retrovirus (a RNA virus) known as Human Immunodeficiency Virus (HIV). AIDS virus attacks white blood cells (WBCs) or lymphocytes of human beings and weakens the human body’s immunity or self-defence mechanism. AIDS becomes prone to many other infections or diseases.

 

<font face="Cambria, serif">Precautions- </font>

<font face="Cambria, serif">i. Avoid using used syringes or blades.</font>

<font face="Cambria, serif">ii. Avoid unprotected physical contact.</font>

 

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  • 2 answers

Sai Swarup 7 years, 1 month ago

Epidermis and Cork cells

Ayus Agarwal 7 years, 1 month ago

Epidermis And cork cells
  • 4 answers

Suraj Kumar 7 years, 1 month ago

It provide flexibility to plant which enable the plant to bend without breaking.

Sai Swarup 7 years, 1 month ago

Present at margins of leaves and resists the tearing effect

Priyanshu Patel 7 years, 1 month ago

Storage of food. Give mechanical strength to plant.

Mannu Bhati 7 years, 1 month ago

it gives mechanical support to leaf or plant
  • 1 answers

Mannu Bhati 7 years, 1 month ago

Solution is a homogeneous mixture and it's size is smaller than 1nm collidrl is a heterogeneous mixture and it's size is BTW 1-1000nm suspension is a heterogeneous mixture and it's size is larger than 1000nm
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Sayoni Debnath 7 years, 1 month ago

Water is a compound because its constituting elements always maintain the fixed ratio of 1:8 whatever may be its source. The composition is uniformly all through the same.

Aditya Sharma 7 years, 1 month ago

What sorry sir please completely the answer

Priyanshu Patel 7 years, 1 month ago

It is pure. Ratio is not fixed. Made up of two or more elements.

Yogesh Mathapati 7 years, 1 month ago

Sorry

Yogesh Mathapati 7 years, 1 month ago

Quit
  • 1 answers

Meghna Thapar 6 years, 1 month ago

Farming is the act or process of working the ground, planting seeds, and growing edible plants. Farming is growing crops or keeping animals by people for food and raw materials.

  • 2 answers

Sayoni Debnath 7 years, 1 month ago

Separating funnel , centrifugation, fractional distillation, crystalization

Akanksha Kumari? 7 years, 1 month ago

1. Distillation 2. Centrifugation 3. Fractional distillation 4. Evaporation
  • 2 answers

Sayoni Debnath 7 years, 1 month ago

Adipose tissue helps in the storage of fat whereas areolar tissue connects the organs together by absorbing shock

Priyanshu Patel 7 years, 1 month ago

Adipose tissue helps in joining the skin to muscles. While areolar tissue helps in storage of fat .
  • 1 answers

Sayoni Debnath 7 years, 1 month ago

No it doesnot violates the law of conservation of energy as the free falling object gains kinetic energy and we know that the sum of the k.e and p.e remains constant
  • 1 answers

Pratik Gurung 7 years, 1 month ago

Postulates of Dalton Atomic theory are: (1)All matter is made of very tiny particles called atomes. (2)Atomes are indivisible particles,which cannot be created nor be destroyed in a chemical reaction. (3)Atoms of a given element are identicle in mass and chemical properties. (4)Atomes of different elements have different masses and chemical properties. (5)Atomes combine in the ratio of small whole numbers to form compounds. (6)The relative number and kinds of atomes are constant in a given compound.
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Sumit Upadhyay 7 years, 1 month ago

If an object's kinetic energy or gravitational potential energy changes, then work is done. The force can act in the same direction of motion. Or, the force can act against the motion. ... In general, the energy transferred depends on the amount of force and the distance over which that force is exerted. Work done=Force x Displacement Work done = (mg) x d

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