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Harvesting -cutting of crops after maturing is know as harvesting. Irrigation -supply of water to crops after a regular interval of time is known as irrigation.

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Describe five method of preservation

Posted by Shubham Gujar 7 years, 1 month ago

CBSE > Class 08 > Science

1 answers

Khushi Ranka 7 years, 1 month ago

Methods that are used to save the food from the attack of pathogenic microorganisms are 1.Chemical methods- Preservation- Chemicals that are added to safe the food from the attack of pathogenic microorganisms. Example-1 Oil and salt are added to pickle. 2 Sodium benzoate and sodium metabisulphite are added in jams and squashes. 2.Common salt- 1use to preserve meat and fish. 2Amla and mango are preserve by salt. 3.Preservation by sugar- Jams ,jelly and squashes are preserved by sugar. 4.Preservation by oil and vinegar-Use of oil and vinegar presents spoilage of pickles because bacteria cannot live in such an environment. 5.Heat and Cold Treatments- Pasteurised milk can be consumed without boiling as it os free from harmful microbes.The milk is heated to about 70°C for 15 to 30 seconds and then suddenly chilled and stored.By doing so,it prevents the growth of microbes.This process was discovered by Louis Pasteur.

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What are testes

Posted by Aniket Gupta 7 years, 1 month ago

CBSE > Class 08 > Science

1 answers

Yogita Ingle 7 years, 1 month ago

The main function of the testes is producing and storing sperm. They’re also crucial for creating testosterone and other male hormones called androgens. The testicles are also part of the endocrine system because they produce hormones, including testosterone . Testosterone is a major part of puberty in guys, and as a guy makes his way through puberty, his testicles produce more and more of it. Testosterone is the hormone that causes guys to develop deeper voices, bigger muscles, and body and facial hair, and it also stimulates the production of sperm.

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Define menstruation in short sentence

Posted by Rakshit Sharma 7 years, 1 month ago

CBSE > Class 08 > Science

4 answers

Vedant Shrivastava 7 years, 1 month ago

If the egg is not fertilised , the lining of the uterus is shed and there is loss of blood . This is known as MENSTRUATION or PERIODS

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Harsvardhan Gupta 7 years, 1 month ago

Period in which egg is released from females body with blood

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Deepak Kumar 7 years, 1 month ago

It is a period of womens in which bleeding take place

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Simran Paranjpe 7 years, 1 month ago

Mensuration is the branch of mathematics which deals with the study of geometric shapes , their area , volume and related parameters

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What changes take place when glass is rubbed woth silk ? What is the result ?

Posted by Gagan Deep 7 years, 1 month ago

CBSE > Class 08 > Science

2 answers

Ayush Saiwal 7 years, 1 month ago

If glass is rubbed with silk then charges of silk will transfer into glass and it will become positively charged

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Sruti Banarjee 7 years, 1 month ago

Due to friction charge is developed.

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Define joule's heating effect of current..

Posted by Sruti Banarjee 7 years, 1 month ago

CBSE > Class 08 > Science

1 answers

Meghna Thapar 5 years, 10 months ago

According to the Joule’s law of heating given by the formula H=I²RT, it is clear that heat produced in a wire is directly proportional to the following three factors:

Square of current, H∞I²
Resistance of wire, H∞R
Time, for which current is passing, H∞T

Therefore, we get

H=I²RT

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Describe male and female reproductive organs in humans

Posted by Sarthak Sangal 7 years, 1 month ago

CBSE > Class 08 > Science

1 answers

Tanuuuu Varshney 7 years, 1 month ago

Male reproductive organs are-: testes, epididymis, sperm duct, and ***** Female reproductive organs are-: ovary, oviduct, uterus, ******

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What is Douplet and Octate rule ?

Posted by Shourya Utkarsh 7 years, 1 month ago

CBSE > Class 08 > Science

1 answers

Yogita Ingle 7 years, 1 month ago

These rules deal with the electronic configuration of elements and chemical bonding.
Duplet rule: It refers to the tendency of atoms to have two electrons in their valence shell by interacting with other atoms either by sharing of electrons or by transferring (gain or loss) of electrons. This rule is only applicable for smaller atoms like hydrogen, helium and lithium.
Octet rule: It refers to the tendency of atoms to have eight electrons in their valence shell by interacting with other atoms either by sharing of electrons or by transferring (gain or loss) of electrons. Element having eight electrons in their outermost (valence shell) are considered to have stable electronic configuration.

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Whatxis douplet and octate rule ?

Posted by Shourya Utkarsh 7 years, 1 month ago

CBSE > Class 08 > Science

1 answers

Yogita Ingle 7 years, 1 month ago

Duplet rule: It refers to the tendency of atoms to have two electrons in their valence shell by interacting with other atoms either by sharing of electrons or by transferring (gain or loss) of electrons. This rule is only applicable for smaller atoms like hydrogen, helium and lithium.
Octet rule: It refers to the tendency of atoms to have eight electrons in their valence shell by interacting with other atoms either by sharing of electrons or by transferring (gain or loss) of electrons. Element having eight electrons in their outermost (valence shell) are considered to have stable electronic configuration.

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What's new here??

Posted by Parwinder Singh 7 years, 1 month ago

CBSE > Class 08 > Science

0 answers

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What is petrochemical????

Posted by Shray Shukla 7 years, 1 month ago

CBSE > Class 08 > Science

1 answers

Tanuuuu Varshney 7 years, 1 month ago

The chemicals which are obtained from petroleum and natural gas are called petrochemical.ex.methyl alcohol

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What are the group of cells

Posted by Dushyanth .Y Dushyanth. Y 7 years, 1 month ago

CBSE > Class 08 > Science

5 answers

Siddhant Sonkar 7 years, 1 month ago

Tissue

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Lucky Kumar 7 years, 1 month ago

Tussues are known as a group of cells.

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Farhan Akhtar 7 years, 1 month ago

Tissue

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Harsh Pandey 7 years, 1 month ago

A group of cells is called a tissue.

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Shivangi Kaptiyal 7 years, 1 month ago

Tissue

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Which clothe thread is completely naturaly

Posted by Praveen Dhakad Dhakad 7 years, 1 month ago

CBSE > Class 08 > Science

2 answers

Harsvardhan Gupta 7 years, 1 month ago

Cotton, jute

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Shray Shukla 7 years, 1 month ago

Nylon is completely naturaly fiber

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How does reproduction take place in animals

Posted by Ekta Sahu 7 years, 1 month ago

CBSE > Class 08 > Science

1 answers

Aditi Jain 7 years, 1 month ago

Reproduction takes place in animals through a process called fertilization. Fertilisation is the fusion of male and female gamates. when female egg cell from mother and the sperm cell from father come in contact, the process of fertilisation takes place and zygote has developed. The zygot then began th form into the embryo and the baby takes place in the mother's uterus. when the emryo gets fully developed and all body parts of the baby can identified, the stage is known as foetus. And after 8 to 9 months the baby come to the world.

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Habitat of the polar bear and the penguin. For each animal explain 2 ways in which it is well adapted to its habitat

Posted by Anand Sadani 7 years, 1 month ago

CBSE > Class 08 > Science

1 answers

Meghna Thapar 5 years, 7 months ago

Polar bears live in the Arctic where the air and water temperatures are very cold. They have special adaptations, or features that help them live in that habitat, like webbed feet, a layer of fat, fur that helps them blend in and dry off, and black skin to absorb the sun's heat. Penguins are found on the exact opposite hemisphere ranging from the Galapagos Islands to the coast of Antarctica. Both the animals have developed attributes to adapt themselves to their habitat. While the penguins are attuned to colours of the sea to protect themselves from predators, the polar bears are white and furry that makes them one with their surroundings. Both the animals eat fish.

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30 one word from ch coal and petroleum

Posted by Siddharth Siddharth 5 years, 9 months ago

CBSE > Class 08 > Science

1 answers

Siddhant Sonkar 7 years, 1 month ago

What are you asking write clearly

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What is the chemical reaction formula for magnesium hydroxide

Posted by Yasir Aftab 7 years, 1 month ago

CBSE > Class 08 > Science

3 answers

Sruti Banarjee 7 years, 1 month ago

Mg(OH)²

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Pratik Satarkar 7 years, 1 month ago

Mg(oh)2

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Siddharth Siddharth 7 years, 1 month ago

Mg (oh)2

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How sun is made and how many gases are required for making sun also tell there %

Posted by Shivam Kumar 7 years, 1 month ago

CBSE > Class 08 > Science

1 answers

Meghna Thapar 5 years, 7 months ago

The Sun is a huge, glowing sphere of hot gas. Most of this gas is hydrogen (about 70%) and helium (about 28%). Carbon, nitrogen and oxygen make up 1.5% and the other 0.5% is made up of small amounts of many other elements such as neon, iron, silicon, magnesium and sulfur.

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What is big ben theory (explain)

Posted by Shivam Kumar 7 years, 1 month ago

CBSE > Class 08 > Science

1 answers

Yogita Ingle 7 years, 1 month ago

Georges Lemaitre (1927) had proposed a model for origin of the universe which became the Big Bang theory. The Big Bang theory explains the origin of universe, with the key idea that the universe is expanding. In the past, the universe was denser and hotter. All of space was contained in a single point, which is considered the inception of the universe. After the initial expansion, the universe freezes that allowed the creation of subatomic particles, consisting of protons, neutrons, and electrons. The majority of atoms formed were hydrogen, along with helium and traces of lithium. Huge clouds of these primal elements later fused through gravity to form stars and galaxies. The massive elements were synthesized either within stars or during supernova. Hence, the Big Bang theory does not explain the initial condition of the universe, but instead it describes the general evolution of the universe.

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How many earth can accommodate in jupitar and sun

Posted by Shivam Kumar 7 years, 1 month ago

CBSE > Class 08 > Science

1 answers

Parampreet Saini 7 years, 1 month ago

1300 earth in Jupiter

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What do you mean by endo plastic reticulum

Posted by Shivam Kumar 7 years, 1 month ago

CBSE > Class 08 > Science

1 answers

Meghna Thapar 5 years, 10 months ago

The endoplasmic reticulum (ER) is a large network of membrane-bound tubes and sheets which looks like long tubules or round or oblong bags (vesicles). There are two types of ER– rough endoplasmic reticulum (RER) and smooth endoplasmic reticulum (SER). RER looks rough under a microscope because it has ribosomes attached to its surface. The ribosomes are the sites of protein manufacture. The SER helps in the manufacture of fat molecules or lipids.

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Are all plastics harmful to us

Posted by Priya Bhagat 7 years, 1 month ago

CBSE > Class 08 > Science

2 answers

Aditi Jain 7 years, 1 month ago

yes, plastics are very harmful as it is non- biodegradable and takes thousands of years to get decompose. when plastics are eaten by some animals like cows or dog from the garbage heaps it is also very harmful for them. The plastic material chokes the respiratory system of these animals, or forms a lining in their stomach and can be the cause of their death.Moreover, plastic makes the soil infertile. When we burn plastics it give poisonous gases. It clogging the drains.

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Parampreet Saini 7 years, 1 month ago

Yes plastic is very harmful to us and our environment too

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What is ****

Posted by Priyanshu Balayan 7 years, 1 month ago

CBSE > Class 08 > Science