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Which gas do you think is superior as fuel -natural gas or liquid petroleum gas? why?

Posted by Mugdha Vaidya 6 years, 4 months ago

CBSE > Class 08 > Science

2 answers

Parneet Kaur 6 years, 3 months ago

Natural gas ????

Divyansh Sharma. 6 years, 4 months ago

Hydrogen not sure

ANSWER

Mention some problems realated to overutilization of fossil fuels?

Posted by Mugdha Vaidya 6 years, 4 months ago

CBSE > Class 08 > Science

1 answers

Yogita Ingle 6 years, 4 months ago

Fossil fuels are the major source of energy and are widely used for all daily-life purposes. But the over-use of these resources might lead to many social and health problems.

• The combustion of fossil fuels emits a lot of toxic gas which is in appropriate for living conditions. These toxic gases are released in the air, causing air pollution.

• This is not only degrading for the environment but also for health. Regular consumption of such toxic gases might cause serious respiratory problems and other life-threatening diseases.

• Fossil fuels are non-renewable source of energy which means that they cannot be made available within a few months or years or even decades.

The formation of fossil fuels takes hundreds of years but due to global warming and high consumption the fossil fuels are also depleting fast.

ANSWER

What are hydrocarbon?

Posted by Mugdha Vaidya 6 years, 4 months ago

CBSE > Class 08 > Science

1 answers

Atul Sinha 6 years, 4 months ago

a compound of hydrogen and carbon, such as any of those which are the chief components of petroleum and natural gas.

ANSWER

What is biofertilizer

Posted by Mukesh Kumar Mukesh Kumar 6 years, 4 months ago

CBSE > Class 08 > Science

1 answers

Yogita Ingle 6 years, 4 months ago

Bio-fertilizers are the substance that contains microbes, which helps in promoting the growth of plants, trees by increasing the supply of essential nutrients to the plants. It comprises of living organisms which include mycorrhizal fungi, blue-green algae, and bacteria. Mycorrhizal fungi preferentially withdraw minerals from organic matter for the plant whereas cyanobacteria are characterized by the property of nitrogen fixation.

ANSWER

Whaat is vaccine?

Posted by Anuradha S 6 years, 4 months ago

CBSE > Class 08 > Science

4 answers

Seema Gupta 6 years, 3 months ago

Vaccines are the substance used to produce immunity in the body.

Ira Ratan Vatsyayan 6 years, 4 months ago

A dead or weakend virus when introduced to a healthy body in order to produce antibodies is known as a vaccine

Zainab Shaikh 6 years, 4 months ago

A medicine or injection give to a person before having the disease is called vaccine.

Anjali Suda 6 years, 4 months ago

No

ANSWER

What role does friction plays in cutting wood

Posted by Ranjita Chandla 6 years, 4 months ago

CBSE > Class 08 > Science

1 answers

Meghna Thapar 5 years, 9 months ago

Friction is defined as the the resistance that one object or surface encounters when moving over another. Friction is a vey useful force. As we know that it is a resisting force, so it also helps in cutting of wood. When a wood is chopped, it creates a friction which cause the wood to chop.

ANSWER

Difference between force and friction

Posted by Harshita Gupta 6 years, 4 months ago

CBSE > Class 08 > Science

3 answers

Rishi Singh 6 years, 3 months ago

Force is a puss or pull that we apply on any object . Friction is the force that is applied opposite the motion of the object

_Aryan_ _Bhende_ 6 years, 4 months ago

Force is like pull and push but non contact forvw

Ranjita Chandla 6 years, 4 months ago

Force is the external agent in the form of push or pull and Friction is the force generated in two Bodies when moving over another.

ANSWER

How are grains stored and prevented

Posted by Pratham Munot 6 years, 4 months ago

CBSE > Class 08 > Science

2 answers

Zainab Shaikh 6 years, 4 months ago

Grains are stored in granaries and silos which safe the grains from insect.

Divyansh Sharma. 6 years, 4 months ago

It can be stored in jute bags and it prevents from get ting spoil or unusable

ANSWER

Which bacteria fixes nitrogen in the root nodles of leguminous plant

Posted by Vandana Raj 6 years, 4 months ago

CBSE > Class 08 > Science

10 answers

Sasikala Subramani 6 years, 3 months ago

Rhizobium

Sameer Sahoo 6 years, 3 months ago

Rhizobium bacteria

Rida Shaheen 6 years, 4 months ago

Rhizobium and blue green algae .

🖤 🖤 6 years, 4 months ago

Rhizobium bacteria Blue green algae

Zainab Shaikh 6 years, 4 months ago

Rhizobium bacteria

Gurleen Kaur 6 years, 4 months ago

Rhizobium

Mishthi Mehra 6 years, 4 months ago

Rhizobium bacteria fixes nitrogen in the root nodles of leguminous plants.

Divyansh Sharma. 6 years, 4 months ago

Rhizobium bacteria by leguminous plant

The Adventurers 6 years, 4 months ago

Rhizobium

Dhruv Agrawal 6 years, 4 months ago

Rhizobium

ANSWER

Explain the activity to demonstrate electrostatic force between two bodies

Posted by Keshav Mundhe 6 years, 4 months ago

CBSE > Class 08 > Science

1 answers

Meghna Thapar 5 years, 10 months ago

The force exerted by an electrically charged object is called electrostatic force. An electrically charged object can exert an electrostatic force on an uncharged object. For example – a plastic comb which is electrically charged by rubbing in dry hair, exerts an electrostatic force on uncharged tiny pieces of paper and attracts them.

ANSWER

Write the functions of different parts of a cell.

Posted by C Roy 6 years, 3 months ago

CBSE > Class 08 > Science

1 answers

Sia ? 6 years, 3 months ago

The ten cell components are:

Plasma membrane: It acts as a semipermeable membrane and allows only selective substances to pass through it.
Chromosomes: To carry hereditary characters of an organism from one generation to another.
Lysosomes: Breakdown of unwanted macromolecules is the main function of these organelles.
Ribosomes: These help in protein synthesis.
Nucleus: Control centre of the cell. It contains cellular DNA (genetic information) in the form of genes.
Mitochondria: The main function of mitochondria in aerobic cells is the production of energy by the synthesis of ATP.
Nucleolus: Biosynthesis of ribosomal RNA (rRNA) and acts as a platform for protein synthesis.
Cell wall: It provides protection and rigidity to the plant cell.
Chloroplasts: These are the sites of photosynthesis within plant cells.
Endoplasmic reticulum: Serves as channels for transport of materials.

ANSWER

What is the means of conservation ?

Posted by Ravi Yadav 6 years, 4 months ago

CBSE > Class 08 > Science

3 answers

Sameer Sahoo 6 years, 3 months ago

The sustainable and optimum utilisation of resources is known as conservation

Harshita Gupta 6 years, 4 months ago

To protect and conserve them for future

Ravi Yadav 6 years, 4 months ago

Conservation means protection of plants and animals.

ANSWER

Cell is a building block like structure

Posted by Ayush Thakur 6 years, 4 months ago

CBSE > Class 08 > Science

1 answers

Sia ? 6 years, 3 months ago

There are three main components of a cell: (i) Cell membrane (ii) Cytoplasm (iii) Nucleus (iv) cell wall.
Cell Membrane: Cell membrane is also called plasma membrane. It makes the boundary of a cell. It is composed of protein and lipid.
Cell Wall: Cell wall is present in plant cells and in bacteria. Cell wall in plants is made up of cellulose. Cell wall gives additional strength and protection to plant cells.
Cytoplasm: A jelly-like substance is present between the cell and nucleus. It is called cytoplasm. Different cell organelles are present in the cytoplasm.
Nucleus: This is a spherical structure which is present inside the cell; usually at the centre of the cell. Nucleus is surrounded by a double membrane called nuclear membrane. A dot-like structure; called nucleolus is present inside the nucleus. Nucleus contains chromosomes which are thread-like structures.

ANSWER

Differences between WBC & amoeba

Posted by Malathy K 6 years, 4 months ago

CBSE > Class 08 > Science

1 answers

Rishi Singh 6 years, 4 months ago

Wbc(Whit Blood Cells)- Wbc helps us to fight desieses . Amoeba - Amoeba is a unnicellular organism that has a nuceleas certain enzymes that help us digest food it also has finger like projection that bulk out from it when it senses food.

ANSWER

Define cell - functions

Posted by Rajni Singh 6 years, 4 months ago

CBSE > Class 08 > Science

2 answers

Racharla Neha 6 years, 4 months ago

Cell is a unit of life.

Zainab Shaikh 6 years, 4 months ago

Cell is the structural and functional unit of an organisms...... It's play a great role in our body.... It is the basic unit and it involve in all body functions as digestion, reproduction etc

ANSWER

Difference between coal and coal tar

Posted by Awesome Gamer 6 years, 4 months ago

CBSE > Class 08 > Science

2 answers

Zainab Shaikh 6 years, 4 months ago

Coal is the pure form of carbon and hard substance and it is also a fossil fuels.... While coal tar is a black thick liquid which is made from about 200 substances.

Mohit Sharma 6 years, 4 months ago

Coal is hard substance and it is black hard poorous substance and coal tar is pure form of coal

ANSWER

what are the functions of choloroplasts

Posted by Davinder Singh Sidhu 6 years, 4 months ago

CBSE > Class 08 > Science

5 answers

Mohit Sharma 6 years, 4 months ago

Colour of plastids is cytoplasm of the leaves .Plastid looks green that called chloroplast contain green pigment that called chlorophyll it provide green clor to leaves it is very important for photosynthesis

Ayesha Khatua 6 years, 4 months ago

Different colour of plastids are scattered in the cytoplasm of the leaves. The plastid that looks green are known as chloroplast. The chloroplast contain green pigment known as chlorophyll that provide green colour to the leaves that is essential for photosynthesis.

Ayesha Khatua 6 years, 4 months ago

Sorry

Ayesha Khatua 6 years, 4 months ago

It is the jelly like substance present between the cell membrane and nucleus . various component or organelles of cell are present in it . These cell organelles are mitochondria , Golgi body etc that floats in it. ?????

Zainab Shaikh 6 years, 4 months ago

Provide green colour to the leaf of the plants...

ANSWER

Explain with the help of an activity that metal oxides are basic oxide

Posted by Shivam Kumar Shivam Kumar 6 years, 4 months ago

CBSE > Class 08 > Science

1 answers

Meghna Thapar 5 years, 10 months ago

When we add water to metallic oxide, it will form hydroxide which turns red litmus blue.

That means it is basic in nature.

Example:

Magnesium oxide, when dissolved in water, forms magnesium hydroxide which is basic in nature.

ANSWER

What are the thread like structure composed of DNA called ?

Posted by Ashok Jain 6 years, 4 months ago

CBSE > Class 08 > Science

4 answers

Seema Gupta 6 years, 3 months ago

Thread like structure inside the chloroplast is known as chromosomes.

Parneet Kaur 6 years, 3 months ago

CHROMOSONES

Zainab Shaikh 6 years, 4 months ago

Thread like structure present in nucleus is called chromosome

Harshita Singh 6 years, 4 months ago

Chromosones

ANSWER

diagram of human penix

Posted by Nikhil Gupta Nikhilgupta 6 years, 4 months ago

CBSE > Class 08 > Science

0 answers

ANSWER

What is the difference between the function of cell membrane and cell wall

Posted by Zainab Shaikh 6 years, 4 months ago

CBSE > Class 08 > Science

1 answers

Seema Gupta 6 years, 3 months ago

Cell membrane is present in animals.cell wall is the outer covering of plant cell.

ANSWER

Difference b/w fossil and fossil fuel

Posted by Ratnajh855Gmail. Com Jh 6 years, 4 months ago

CBSE > Class 08 > Science

1 answers

Meghna Thapar 5 years, 10 months ago

Fossils are the remains of pre-historic plants or animals, buried under the earth millions of years ago. However, fossil fuels are hydrocarbons, primarily coal, fuel oil or natural gas, formed from the remains of dead plants and animals.

ANSWER

Did virus can produces antibodies

Posted by Hariom Choudhary 6 years, 4 months ago

CBSE > Class 08 > Science

2 answers

Sameer Sahoo 6 years, 3 months ago

No, micro organisms only can produce antibiotics

Saroj Dhayal 6 years, 4 months ago

No

ANSWER

How the microorganisms are friends and foe

Posted by Angel Arora 6 years, 4 months ago

CBSE > Class 08 > Science

1 answers

Anagha Avinash 6 years, 4 months ago

Microorganisms are useful to us in some ways. Like: Making of curd Making of vaccines Antibiotics Alcohol. Etc Microorganisms are harmful too in some ways.Like: Cause diseases Spoil food. Etc By this, microorganisms help us in some ways while harm us too in some ways. They are our friends as they help us in some ways and are our foe (rival) as they are harmful to us in some ways.

ANSWER

What is blue revolution and white revolution

Posted by Angel Arora 6 years, 4 months ago

CBSE > Class 08 > Science

1 answers

Sameer Sahoo 6 years, 3 months ago

Blue revolution related to fish and white revolution related to milk

ANSWER

Atmospheric pressure and name device which is used to it

Posted by Murdhar Kanwar 6 years, 4 months ago

CBSE > Class 08 > Science

2 answers

Parneet Kaur 6 years, 3 months ago

ATMOSPHERIC PRESSURE-: pressure exerted by air on an object BAROMETER is used to measure atmospheric pressure

Yogita Ingle 6 years, 4 months ago

Atmospheric pressure is the air pressure which is exerted by the weight of air present in the atmosphere.
The common unit for expressing and measuring atmospheric pressure is millimetres of mercury .The atmospheric pressure on the surface of earth is 760 mm of mercury.

ANSWER

Purpose of deforestation

Posted by Shweta Yadav 6 years, 4 months ago

CBSE > Class 08 > Science

3 answers

Harshita Gupta 6 years, 4 months ago

It refers to the cutting of trees on a large scale

Mugdha Vaidya 6 years, 4 months ago

It involves cutting of tree

Anagha Avinash 6 years, 4 months ago

Deforestation is a bad practice . Anyways it involves cutting trees on a large scale .wood is used to manufacture furniture, firewood,cricket bat,carvings etc. Wood is required to produce all of these . Therefore deforestation is practised to continue business

ANSWER

Choose the correct options.

(1). Yeast and moulds are examples of

(a). Fungus (b). Bacteria (c). Algae (d). Virus

(2). Which of these microorganisms is used in the preparation of bread.

(a). Yeast (b). Algae (c). Bacteria (d). Virus

(3). Food spoilage can be detected by.

(a). Foul (b). Surface discolouration (c). Sour taste (d). All of these.

(4) prodction of alcoholic beverages such as beer and wine involves.

(a). Pasteurization (b). Fermentation (c). Tanning (d). Non of these.

(5). Which of the following is a method of food preservation.

(a). Boiling (b). Canning (c) Dehydration (d) all of these.

Posted by Syed Daniel 6 years, 4 months ago

CBSE > Class 08 > Science

3 answers

Sameer Sahoo 6 years, 3 months ago

01) Fungi 03) All of these 04)Fermentation 05) Canning

Harshita Gupta 6 years, 4 months ago

1)fungus 2)yeast 3)all of these 4)fermentation 5)boiling

Anagha Avinash 6 years, 4 months ago

1) (b) bacteria 2) (a) yeast 3) (d) all of these 4) (b) fermentation 5) (b) canning Hope it helps

ANSWER

Which of the following affects the Ozone layer?

Posted by Er Dhruv Kumar Gupta 6 years, 4 months ago

CBSE > Class 08 > Science

1 answers

Sameer Sahoo 6 years, 3 months ago

Chloroflurocarbon

ANSWER

Cooking utensils are good conductor

Posted by Jagruti Parmar 6 years, 4 months ago

CBSE > Class 08 > Science

2 answers

Zainab Shaikh 6 years, 4 months ago

Obviously!

Harshita Gupta 6 years, 4 months ago

Yes, cooking utensils are good conductor of heat

ANSWER

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