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Polypropylene (PP) is a thermoplastic “addition polymer” made from the combination of propylene monomers. It is used in a variety of applications to include packaging for consumer products, plastic parts for various industries including the automotive industry, special devices like living hinges, and textiles. Polypropylene was first polymerized in 1951 by a pair of Phillips petroleum scientists named Paul Hogan and Robert Banks and later by Italian and German scientists Natta and Rehn.

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What is vaccine Please answer fast I need it now...

Posted by Trisha Raj 7 years, 8 months ago

CBSE > Class 08 > Science

1 answers

Manav M? 7 years, 8 months ago

Abe challna kyu mai tera question ko answer karu

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'Manufacturing synthetic fibres is actually helping conservation of forests. Comment?

Posted by Murtaza Aftab 7 years, 8 months ago

CBSE > Class 08 > Science

2 answers

Ayush Gupta 7 years, 8 months ago

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Bhaiya Kunal Sinha 7 years, 8 months ago

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Who is discover of cell

Posted by Amisha Rajvansi 7 years, 8 months ago

CBSE > Class 08 > Science

4 answers

Vaishnavi Poste 7 years, 8 months ago

Alexander

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Ayush Gupta 7 years, 8 months ago

robert hookey was discovered the cell

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Sanskriti Prachi 7 years, 8 months ago

Robert hook

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Supriya Sharma 7 years, 8 months ago

Alexander

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What is microorganisms ? Type also.

Posted by Vansh Sharma 7 years, 8 months ago

CBSE > Class 08 > Science

3 answers

Ayush Gupta 7 years, 8 months ago

the small organisms wich we cannot see from the naked eye are called microorganism. and the types are bactrea, viruses,

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Subhrajeet Das 7 years, 8 months ago

Types of microorganisms are_1) Bacteria 2) Fungi 3)Protozoa 4)Algae

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Subhrajeet Das 7 years, 8 months ago

The small living organisms which lives around us which we normally cannot see.Those are called microorganisms

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What is irragation

Posted by Shivin Sharma 7 years, 8 months ago

CBSE > Class 08 > Science

3 answers

Palakpreet Kaur 7 years, 8 months ago

Supply of water at regular interval is called irragation

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Sukhjinder Paul Singh 7 years, 8 months ago

The process of providing water to the crops is called irrigation.

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Vinod Test Pandey 7 years, 8 months ago

The process of watering the feild is caleed irrigation

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Tractor have a large tyres,bulldozers have catterpillar tracks and heavy buses/trucks have 8 rear wheels giv e reason for all theses

Posted by Chamru Satisfiya 7 years, 8 months ago

CBSE > Class 08 > Science

1 answers

Arshdeep Singh 7 years, 8 months ago

Because large Tyre increase friction between Tyre and surface to move easily.

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what is the use of sperm tail in human sperm

Posted by Ayush Gupta 7 years, 8 months ago

CBSE > Class 08 > Science

1 answers

Yogita Ingle 7 years, 8 months ago

A sperm cell is the male reproductive cell and a mature human sperm cell has snake like structure. A male sperm cell comprises the following parts - head, neck, middle piece and tail.
The head carries the genetic information, neck contains enzymes, middle piece supplies energy to the sperm and the tail helps the sperm to swim in the female genital tract.
The sperm cell has a long tail like flagella. The tail is made of protein fibres which contract on alternative sides, giving it a wavelike movement (snake-like motion). The main function of the tail; is the propulsion system which means it helps in propelling or swim the sperm cell forward to meet the egg. It is extremely important that the sperm moves forward instead of laterally or in circles.

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Describe fertilisation in human beings

Posted by Ashukur Rahman 7 years, 8 months ago

CBSE > Class 08 > Science

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How many organ have

Posted by Pavan Srivastav 7 years, 8 months ago

CBSE > Class 08 > Science

0 answers

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Why virus is not counted in catogary of microbes

Posted by Sourav Kumar 5 years, 9 months ago

CBSE > Class 08 > Science

1 answers

Aditya Sarthak 7 years, 8 months ago

Besause virus act like both living and non living if it is live on nonliving it reacts like nonliving

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Rana wants to buy shirts for summer . should he buy cotton shirts or shirts made from synthetic material ? advise Rana , giving your reason.

Posted by Himanshu Rawat 7 years, 8 months ago

CBSE > Class 08 > Science

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Cell structure

Posted by Chitransh Sahu 7 years, 8 months ago

CBSE > Class 08 > Science

1 answers

Yogita Ingle 7 years, 8 months ago

Following are the main parts of a cell:
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.
Prokaryotes: When genetic materials are not organized in the form of nucleus, the organism is called prokaryote.
Eukaryotes: When genetic materials are organized in the form of nucleus, the organism is called eukaryote.
Protoplasm: The fluid inside the cell is called protoplasm. Protoplasm is composed of cytoplasm and nucleoplasm.
Vacuoles: Some fluid-filled bag-like structures can be seen inside a cell. These are called vacuoles.
Plastids: Plastid is an important cell organelle and is found in plant cells only.

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Why should we conserve biodiversity

Posted by Ayushy Kushwaha 7 years, 8 months ago

CBSE > Class 08 > Science

1 answers

Siddhi Gupta 7 years, 8 months ago

Human should conserve biodiversity because of its benefit for example services and biological resources which are essential to live our life on earth. However, it also provides spiritual benefits as well as social benefit.

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Define synthetic fibers.

Posted by Naman Singh 7 years, 8 months ago

CBSE > Class 08 > Science

3 answers

Siddhi Gupta 7 years, 8 months ago

Definition of synthetic fiber : any of various man-made textile fibers including usually those made from natural materials (such as rayon and acetate from cellulose or regenerated protein fibers from zein or casein) as well as fully synthetic fibers (such as nylon or acrylic fibers

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Himanshu Rawat 7 years, 8 months ago

synthetic fibres are human made fibres . These fibres are made with the help of chemicals in laboratory.

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Sanjeet Singh 7 years, 8 months ago

Synthetic fibres are the fibres which catch heat quickly. These fibres are harmful for us.

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What is protozoa? What is present in it ?

Posted by Zara Chauhan 7 years, 8 months ago

CBSE > Class 08 > Science

2 answers

Palakpreet Kaur 7 years, 8 months ago

Protozoa causes serious diseases like malaria

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Vansh Sharma 7 years, 8 months ago

Protozoa is a microorganisms which cause dysentery and malaria.

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Food

Posted by Ravi Sirvi 7 years, 8 months ago

CBSE > Class 08 > Science

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Write five points of bacteria

Posted by Fahad Azmi 7 years, 8 months ago

CBSE > Class 08 > Science

1 answers

Yogita Ingle 7 years, 8 months ago

Bacteria are known for their simple body design. They are single-celled microorganisms with the absence of the nucleus and other cell organelles. They are prokaryotic organisms which are present almost everywhere around us from soil to human guts.
Bacteria are grouped into five based on their shapes such as rod-shaped bacilli, spherical, cocci, spiral-shaped spirilla, and corkscrew spirochaetes. They may either be in clusters or chains or pairs or single. Another criterion for classification of bacteria is by using of staining techniques. For e.g. Gram-positive and Gram-negative bacteria.

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y=log(1/e^x)

Posted by Prabal Sharma 7 years, 8 months ago

CBSE > Class 08 > Science

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Write five points at bacteria

Posted by Umar Umarazmi 7 years, 8 months ago

CBSE > Class 08 > Science

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What is the sugar formal

Posted by Tanishq Saini 7 years, 8 months ago

CBSE > Class 08 > Science

0 answers

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What is nitrate

Posted by Abhijeet Kumar 7 years, 8 months ago

CBSE > Class 08 > Science

2 answers

Siddhi Gupta 7 years, 8 months ago

Nitrates are the most water soluble of all salts, and play a major part in nitrogen cycle and nitrate pollution.

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Varun Raghuwanshi 7 years, 8 months ago

The water soluble Nitrogen is known as Nitrates

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Why is excessive irrigation harmful for plants

Posted by Rudra Chanda 7 years, 8 months ago

CBSE > Class 08 > Science

2 answers

Siddhi Gupta 7 years, 8 months ago

Too much water actually is bad for most of our trees and plants. If soil becomes water logged and stays that way as poorly draining clay soil tends to do the water can cut off the air supply to the roots and to the microorganisms that live in healthy soil. It can lead to root rot or other diseases. HENCE EXCESS IRRIGATION IS HARMFUL TO THE CROPS

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Anish Musti 7 years, 8 months ago

Water is very important for the growth of plants but excessive irrigation of field leads to water logging of soil. Too much water is harmful for crop production as discussed under: ... This is due to excessive water in the field, which affects the soil aeration.

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Chromosome in the human and monkey

Posted by Jahnavi Kumari 7 years, 8 months ago

CBSE > Class 08 > Science

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What is microrangism

Posted by Dixita Sharma 7 years, 8 months ago

CBSE > Class 08 > Science

5 answers

Naman Singh 7 years, 8 months ago

The organisms which are not visible to the naked eye are called microorganisms.For e.g:-protozoa,paramoecium etc.

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Shweta Sharma 7 years, 8 months ago

Very tiny and small organisms wich we can not see with naked eye we can only see them through micro scope

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Aditi Jain 7 years, 8 months ago

Organisms that we normally cannot see with naked eyes but can be see only with the help of microscope. These organisms are called microorganisms.

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Abhijeet Kumar 7 years, 8 months ago

They can't be seen by a naked eye because they are too small.

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Jahnavi Kumari 7 years, 8 months ago

Organisms that can be not seen by the naked eyes

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Define between fertiliser and manure

Posted by Shah Khushi A 7 years, 8 months ago

CBSE > Class 08 > Science

2 answers

Aditi Jain 7 years, 8 months ago

Fertilisers: 1) fertiliser is a man made inorganic salt. 2) fertiliser is prepared in factories. 3) fertiliser does not provide any humus to the salt. 4) fertilisers are very rich in plant nutrients like nitrogen, phosphorus, and potassium. Manure: 1) manure is a natural substance obtained by the decomposition of cattle dung and plant residues. 2) manure can be prepared in the fields. 3) manure provides a lot of humus to the soil. 4) manure is relatively less rich in plant nutrients.

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Siddhi Gupta 7 years, 8 months ago

Fertilizer : 1 . Made from chemical substance 2 .easy to carry 3 . Increase the yield of the soil Manure: 1 .obtain from biodegradable substances. 2 .not able to carry easily. 3 .increse the fertility of the soil.

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What is contact force

Posted by Laxmi Maheshwari 7 years, 8 months ago

CBSE > Class 08 > Science