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About 300 million years ago the earth had dense forest in low lying wetland areas.Due to natural processes like flooding ,these forest got buried under the soil .As more soil got deposited over them ,they were compressed.The temperature also rose as they sank deeper and deeper .under high pressureand high temperature ,dead plants got converted to coal.

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Give one important use of algae

Posted by Mahi Raj 7 years, 5 months ago

CBSE > Class 08 > Science

3 answers

Shreshta M Asunde 7 years, 5 months ago

In China and Japan algae is used as vegetable and they make soup and drink it.

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Sonali Aggarwal 7 years, 5 months ago

The blue-green algae have the ability to fix the nitrogen gas of the atmosphere.

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Akshit Awasthi 7 years, 5 months ago

Algae is used in wastewater treatment facility

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Which gas in gasstove

Posted by Deepti Agrawal 7 years, 5 months ago

CBSE > Class 08 > Science

0 answers

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Classify bacteria on the basis of thier shape

Posted by Naga Pallavi 7 years, 5 months ago

CBSE > Class 08 > Science

1 answers

Nalli Hansini 7 years, 5 months ago

Bacteria are classified into 5 groups according to their basic shapes: spherical (cocci), rod (bacilli), spiral (spirilla), comma (vibrios) or corkscrew (spirochaetes). They can exist as single cells, in pairs, chains or clusters.

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What are mettlaoids

Posted by Abhishek Verma 7 years, 5 months ago

CBSE > Class 08 > Science

1 answers

Meghna Thapar 5 years, 7 months ago

A metalloid is a chemical element that exhibits some properties of metals and some of nonmetals. Metalloids are elements with properties intermediate between those of metals and non-metals. Silicon is a metalloid because it has luster, but is brittle. Boron, arsenic, and antimony are metalloids with a variety of uses. Boron, silicon, germanium, arsenic, antimony, tellurium, and polonium are metalloids. In some cases, authors may also class selenium, astatine, aluminum, and carbon as metalloids, but this is less common.

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Deasease with fungi

Posted by Irshad Khan 7 years, 5 months ago

CBSE > Class 08 > Science

1 answers

Shreshta M Asunde 7 years, 5 months ago

Ringwarms, Dobi's ich, smut etc..

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What is nitrogen cycle??????

Posted by Arpita Kumari 7 years, 5 months ago

CBSE > Class 08 > Science

1 answers

Meghna Thapar 5 years, 7 months ago

The circulation of nitrogen element through living things and non-living environment is called nitrogen cycle in nature. The main steps involved in nitrogen cycle are:

The nitrogen fixing bacteria present in the soil and in the root nodules of leguminous plants, blue-green algae and lightning in the sky fix atmospheric nitrogen and convert it into compounds of nitrogen which go into the soil.
The roots of the plants absorb compounds of nitrogen from the soil for their growth and convert them into plant proteins and other organic compounds which make up the body of the plants.
The plants are eaten up by animals as food. Animals convert plant proteins into animal proteins and other organic compounds which make up their body.
When plants and animals die the complex nitrogen compounds present in their dead bodies are decomposed and converted into simple compounds of nitrogen by certain bacteria and fungi present in the soil.
Certain bacteria convert some part of nitrogen compounds into atmospheric nitrogen which goes back into the atmosphere and thus the amount of nitrogen content remains more or less constant.

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What is nitrogen fixation???????

Posted by Arpita Kumari 7 years, 5 months ago

CBSE > Class 08 > Science

1 answers

Sonali Aggarwal 7 years, 5 months ago

Nitrogen fixation is a chemical process that converts atmospheric nitrogen into ammonia, which is absorbed by organisms. Nitrogen fixation is essentially converting atmospheric nitrogen into a form that plants can more readily utilize.

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How coal formation in the earth?

Posted by Ananta Pant 7 years, 5 months ago

CBSE > Class 08 > Science

2 answers

Sonali Aggarwal 7 years, 5 months ago

About 300 million years ago,the earth had dense forests in low lying wet land areas.Due to natural processes like earthquakes,volcanoes and floods,etc.,these forests were buried under the surface of the earth.As more soildeposited over them,they were compressed.The temperature also rose as they sank deeper and deeper. Due to high pressure and high temperature inside the earth, and in the absence of air, the wood of buried forest plants and trees was slowly converted into coal.

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Radhika Parwal 7 years, 5 months ago

Remains dead plants and animals which were buried under the earth for millions of years got converted by the heat and pressure into fossil fuels

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What are fossils fuel?

Posted by Ananta Pant 7 years, 5 months ago

CBSE > Class 08 > Science

2 answers

Vijeta Chaudhary 7 years, 5 months ago

A fossil fuel is a source of energy which is formed from the accumulated remains of dead organisms that were buried under millions of year ago

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Radhika Parwal 7 years, 5 months ago

Remains dead plants and animals

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What does we obtain when CuSO4+Zn mixed in a beaker for 2 days. Also we do with CuSO4+Fe mixed. Again mixed ZnSO4+Cu. Again mixed FeSO4+Cu. Again mixed ZnSO4+Fe What happen in this experement .

Posted by Utkarsh Kumar 7 years, 5 months ago

CBSE > Class 08 > Science

0 answers

ANSWER

What are natural resources and differentiste between boigas and natural gas

Posted by Khushi Tanwar 7 years, 5 months ago

CBSE > Class 08 > Science

1 answers

Abhay Pratap Singh Chauhan 7 years, 5 months ago

i)The resources which occurs naturally are called natural resources.Eg.coal, petroleum. ii) a) a)biogas - gas which occurs by chemical engineering are called biogas. b)the gases which occurs naturally are called natural.Eg.co2,o2,n2

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Advantages of using cng and lpg as fuels

Posted by Yash Anand 7 years, 5 months ago

CBSE > Class 08 > Science

2 answers

Kalu Choudhury 7 years, 5 months ago

1.it is a non polluting fuel for vehicle. 2.these are used for power generations. 3.these are used directly for burning in homes and factories. 4.these are easily available.

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Sumathi M 7 years, 5 months ago

They are less pollutant fuel

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what are the organic food

Posted by Ritika Sharma 7 years, 5 months ago

CBSE > Class 08 > Science

1 answers

Yogita Ingle 7 years, 5 months ago

Organic foods are defined as those foods that are grown without the use of synthetic fertilizers, sewage sludge, irradiation, genetic engineering, pesticides, or drugs. Pesticides are chemical or control agents made to kill insects, weeds, and fungal pests that damage crops.

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What are the advantages of fertilisers

Posted by Sampath Netinti 7 years, 5 months ago

CBSE > Class 08 > Science

2 answers

Vinay Kapri 7 years, 5 months ago

1)Fertiliser is an organic salt. 2)Fertiliser is prepared in factories. 3)fertiliser don't provide any humus to soil.

2Thank You

Adwaith Santhosh 7 years, 5 months ago

Fertilizer are rich in nutriens such as nitrogen .

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ANSWER

What are antibiotics? What precaution must be taken while taking antibiotics?

Posted by Amardeep Charan 7 years, 5 months ago

CBSE > Class 08 > Science

1 answers

Rushika.K Shankar 7 years, 5 months ago

Antibiotics are medicines against bacterias, they kill the bacteria in our body, hence the doctor will prescribe antibiotics when you are sick with bacterial infections. doctors will explain about certain precautions to be taken when you take antibiotic like to be consumed on an empty stomach, or after food, not to take with milk etc.

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What is fermentation?

Posted by Darsh Patel 7 years, 5 months ago

CBSE > Class 08 > Science

2 answers

Rushika.K Shankar 7 years, 5 months ago

fermentation is a process where certain bacteria or sometimes yeast will convert an existing liquid to some other liquid. eg curd, wine etc

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Siddhi Gupta 7 years, 5 months ago

The process conversion of sugar into alcohol or acid is called fermentation.

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Why more water is needed to plant in summer season?

Posted by J Kanishka 7 years, 5 months ago

CBSE > Class 08 > Science

1 answers

Santosh Meher 7 years, 5 months ago

Because in summer the percentage of the water in the soil is less. So the plant can't take water from the soil. For this more water must be needed to plants in summer otherwise it may die.

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What are microbes?disesases caused by microbes?

Posted by Anjali 7 years, 5 months ago

CBSE > Class 08 > Science

1 answers

Siddhi Gupta 7 years, 5 months ago

Microbes are those organisms that cannot be seen through naked eyes but with the help of an euipment called microscope. There are many diseases caused micbrobes such as common cold , typhoid, malaria, ringworm etc are the disease caused in humans by microbes. Disease caused in plants by microbes are citrus canker, apple scab , septoria leaf blotch etc. Disease caused in animals by microbes are anthrax,finrot,etc.

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What is mean by light

Posted by Riya Bisht 7 years, 5 months ago

CBSE > Class 08 > Science

2 answers

Ankit Sharma 7 years, 5 months ago

Light is a wave which comes from up,flashlight,etc

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Amandeep Kaur 7 years, 5 months ago

Yxfhxyhl

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Why is lubrication important

Posted by Shubham Choudhury 7 years, 5 months ago

CBSE > Class 08 > Science

1 answers

Siddhi Gupta 7 years, 5 months ago

It is important in order to reduce frictio so that there will be no wear and tear of the machine.

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Why is

Posted by Shubham Choudhury 7 years, 5 months ago

CBSE > Class 08 > Science

0 answers

ANSWER

What is threshing What is winnowing

Posted by Silfa Tj 7 years, 5 months ago

CBSE > Class 08 > Science

1 answers

Shubham Choudhury 7 years, 5 months ago

The process of beating out the grains from the harvested crop plants is called threshing.The process of separating grains from chaff and hay with the help of wind is called winnowing

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Paragraph on threshing

Posted by Bansari Patel 7 years, 5 months ago

CBSE > Class 08 > Science

1 answers

Ankit Sharma 7 years, 5 months ago

Sepration of grain from the bulk of harvested plants is called threshing.

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Paragraph on weeding

Posted by Bansari Patel 7 years, 5 months ago

CBSE > Class 08 > Science

1 answers

Anjana Prasad 7 years, 5 months ago

Weeding means the unwanted plants that grow with grains.

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What is the role of nitrogen fixing bacteria in increasing the soil fertity

Posted by Arpit Shivhare 7 years, 5 months ago

CBSE > Class 08 > Science

1 answers

Yogita Ingle 7 years, 5 months ago

The conversion of atmospheric nitrogen into nitrogenous compounds is nitrogen fixation. Some microorganisms reside in the root nodules of leguminous plants. They can fix nitrogen from air into soil and increase the soil fertility. Some bacteria and blue green algae present in the soil fix nitrogen from the atmosphere and convert into nitrogenous compounds.

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WHY THE SEA DIVER WEAR DIFFERENT CLOTHS?

Posted by Upendra Solanki 7 years, 5 months ago

CBSE > Class 08 > Science