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How soil pollution can be preventer

Posted by Bikash Kar 6 years, 3 months ago

1 answers

.. ... 6 years, 3 months ago

Soil pollution can be prevented by :- 1.Cultivation by natural fertilisers and not using the toxic pesticides and artificial fertilisers. 2. avoid dumping of industrial waste, acidic precipitates etc in to the soil. 3. avoid using detergents. 4.afforestation,use other dustbins for throw biodegradable and non-

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How many types of Hydrocarbon

Posted by Asmit Maurya 6 years, 3 months ago

CBSE > Class 07 > Science

3 answers

Asmit Maurya 6 years, 3 months ago

There are 3 types of hydrogen carbo

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Binod Dwivedi 6 years, 3 months ago

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.. ... 6 years, 3 months ago

Compounds like methane, butane, propane, and hexane are all hydrocarbons. Their chemical formulas consist of only carbon and hydrogen atoms, in a variety of ratios and chemical configurations.

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What do you understand by indicators

Posted by Nitin Singh 6 years, 3 months ago

CBSE > Class 07 > Science

2 answers

Pallavi Mansingh 6 years, 3 months ago

Indicatirs are special types of substances which have different colours and different mediums and are used to test whether a solution is acidic, basic or nuetral. For eg. turmeric(natural indicator), methyl orange (synthetic indicator).

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Uma Bhati 6 years, 3 months ago

Indecators are substances which when added in a solution show a change in colour ,indicating whether it is an acid or basic solution

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What is wind what causes it

Posted by Atul Yadav 6 years, 3 months ago

CBSE > Class 07 > Science

1 answers

.. ... 6 years, 3 months ago

Wind is the flow of gases on a large scale. Wind is caused by differences in the atmospheric pressure. When a difference in atmospheric pressure exists, air moves from the higher to the lower pressure area, resulting in winds of various speeds. On a rotating planet, air will also be deflected by the Coriolis effect, except exactly on the equator.

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Waste water released by houses

Posted by Vansh Kumar 6 years, 3 months ago

CBSE > Class 07 > Science

1 answers

.. ... 6 years, 3 months ago

Sewage is wastewater released by homes, industries, hospitals, offices and other users. It also includes rainwater that has run down the street during a storm or heavy rain. The water that washes off roads and rooftops carries harmful substances with it. Sewage is a liquid waste.

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What is called soil profile

Posted by Kochurani Jose 6 years, 3 months ago

CBSE > Class 07 > Science

4 answers

Kishlay T 6 years, 3 months ago

A vertical section through different layers of soil is called soil profile

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Arpita Singh 6 years, 3 months ago

The vertical sections of soil is called soil profile

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Yogita Ingle 6 years, 3 months ago

Different layers of soil are called soil horizons and the cross sectional arrangement of these layers in soil is called soil profile.
Each layers of soil have different texture and color, different depth and varying chemical composition.
Layers of soil can be seen while digging a well or when the foundation of a building is laid.

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Ganesh Kajal 6 years, 3 months ago

vertical section through different layers of the soil is called the soil profile

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What is rusting? How do we provent rusting

Posted by Rajat Mali 6 years, 3 months ago

CBSE > Class 07 > Science

2 answers

Kishlay T 6 years, 3 months ago

Keep a iron piece

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Yogita Ingle 6 years, 3 months ago

Rusting: If articles made of iron are left in open air for some time, they get coated with a brown powdery substance, called rust. This process of iron changing into rust is called rusting.
Rusting is a slow oxidation process, where metal slowly reacts with atmospheric oxygen to form Metal oxide.
Rusting can be prevented by adopting any of these methods:

By painting on the surface of iron prevents the direct contact of the surface with the atmosphere. Thus prevents the reaction between Iron surface and oxygen of the atmosphere.
By oiling the surface of Iron.
Using anti-rust solutions also can prevent the rusting process. In general alkaline solutions of Chromate salts and Phosphate salts are used as anti-rust solutions.

• Galvanisation - It is the process of depositing a layer of zinc on iron.
• Alloy formation - Stainless steel is an alloy.

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What is wather cycle

Posted by Pokemon Master 6 years, 3 months ago

CBSE > Class 07 > Science

2 answers

Pokemon Master 5 years, 11 months ago

Can you explain two ways in which you think advertising affects issues of equality in a democracy

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Yogita Ingle 6 years, 3 months ago

Water cycle is the cyclic movement of water from the atmosphere to the earth and back to the atmosphere through various processes. This constant, never ending circulation of water in nature is known as the water cycle.
The process includes:
Evaporation: Water in seas, rivers, lakes, ponds or streams evaporates because of the heat of the sun.
Transpiration: Plants give out a large amount of water through their leaves
Condensation: Water vapor rises up and condenses on dust particles to form cloud.
Precipitation: Water stored in clouds reaches the ground in the form of rain, hail or snow.

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What is convex mirror

Posted by Omkar Singh 6 years, 3 months ago

CBSE > Class 07 > Science

1 answers

.. ... 6 years, 3 months ago

__convex mirror is a curved mirror in which the reflective surface bulges toward the light source. Convex mirrors reflect light outwards, therefore they are not used to focus light. ... The image is smaller than the object, but gets larger as the object approaches the mirror.

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Rbc ka work kya hai

Posted by Vinod Kumar Vinod Kumar 6 years, 3 months ago

CBSE > Class 07 > Science

2 answers

Ashutosh Katyan 6 years, 3 months ago

The most important function of red blood cells is the transport of oxygen (O2) to the tissues. The hemoglobin absorbs oxygen in the lungs. Then it travels through blood vessels and brings oxygen to all other cells via the heart.

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.. ... 6 years, 3 months ago

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Our body is a good and bad conductor of electricity

Posted by Hradik Singh 6 years, 3 months ago

CBSE > Class 07 > Science

3 answers

Aishwarya Gupta 6 years, 3 months ago

Our body is good conducter of electricity

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Vikash Kumar 6 years, 3 months ago

Good conductor

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.. ... 6 years, 3 months ago

The flow of charges and ions constitute an electric current. As our body cells contain various ions like sodium ion, potassium ion, chloride ion etc which have the tendency to conduct electricity and this makes our body good conductor of electricity. ▶The human body is generally not a good conductor. That said, there are circumstances which can and do conspire to make the human.

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How cyclone form?

Posted by Mahendra Pratap 6 years, 3 months ago

CBSE > Class 07 > Science

1 answers

.. ... 6 years, 3 months ago

The most air over the sea and ocean gets heated by sun rays and rises up creating a low pressure region. This warm air get cool and starts condensing. During condensation heat is released and air around it gets warm. This warm air rises upwards creating a low pressure region. This space is filled by cooler air. This cycle of events continue till a very low pressure system with very high speed winds revolving around it is formed. This forms cyclone.

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What are characteristics of fossil fuels

Posted by Jashan Batth 6 years, 3 months ago

CBSE > Class 07 > Science

1 answers

Yogita Ingle 6 years, 3 months ago

Characteristic Features of Fossil Fuels

1. Combustible: Fossil fuels are highly combustible in the presence of heat and oxygen.
2. Natural: Fossil fuels are formed naturally over millions of years by the pressure of rock and sediment on the bodies of plants and animals that died far back in the geological past.
3. Abundance: Fossil fuels are abundant throughout the world. Russia is abundant in natural gas, for instance, whilst Saudi Arabia has an abundance of oil.
4. Limited: Its true that the supply of fossil fuels are in abundance. But the supply of fossil fuels is not unlimited, it is limited as they take such a long time to form.
5. Concentrated energy: Fossil fuels are powerful sources of energy.
6. Composition: Fossil fuels are very rich in carbon.

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What is sublimation

Posted by Jasvinder Kaur 6 years, 3 months ago

CBSE > Class 07 > Science

1 answers

.. ... 6 years, 3 months ago

Sublimation is the transition of a substance directly from the solid to the gas phase, without passing through the intermediate liquid phase.

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How can we write the definition of rusting?????

Posted by Khushi Sharma 6 years, 3 months ago

CBSE > Class 07 > Science

3 answers

Arpita Singh 6 years, 3 months ago

When iron comes in contact of air Fe(iron) +O2 =Fe2O3

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Jasvinder Kaur 6 years, 3 months ago

When an iron object is expose in air & humid air covered with. The formation of rust on an iron object is called rusting of iron

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.. ... 6 years, 3 months ago

When Iron comes in contact with moisture and oxygen , the chemical process if rusting takes place. A brown colour substance forms around that metal which makes it rough and damages its plain surface. The process of rusting can be well - understood by the following equation.. 4 Fe(s) + 6 H2O(l) + 3 O2(g) → 4 Fe(OH)3(s) i.e. Iron + Water + Oxygen = Rust To prevent rust.... You can apply the following methods... i) Silver Coating ii) Galvanization iii) Lubrication

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What is the chemical name of lemon water

Posted by Neeru Arora 6 years, 3 months ago

CBSE > Class 07 > Science

2 answers

Tanya Gupta 6 years, 3 months ago

C6H8O7

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Piyush Kumar 6 years, 3 months ago

C6H8O7

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When there is a physical and chemical change in digestion of food

Posted by Vimal Kumar 6 years, 3 months ago

CBSE > Class 07 > Science

5 answers

Swayam Gupta 6 years, 3 months ago

It is chemical change

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Vikash Kumar 6 years, 3 months ago

Chemical

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Jasvinder Kaur 6 years, 3 months ago

It is chemical change because we can't obtain molecules

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Shashank Shekhar 6 years, 3 months ago

Chemical change

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Piyush Kumar 6 years, 3 months ago

Chemical change

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What is the mode of transfer of heat

Posted by Ayushi Dwivedi Ayushi Dwivedi 6 years, 3 months ago

CBSE > Class 07 > Science

5 answers

Pallavi Mansingh 6 years, 3 months ago

Transfer of heat is caused by the molecules of the matter to expand and pass on the heat (transfer the heat). There are three modes of transfer of heat : 1) CONDUCTION- The transfer of heat from a hotter end to a cooler end, it takes place in solids. For eg.a spoon kept in a glass of warm water. 2) CONVECTION-The transfer of heat in which the hotter portion rises and the cooler portion sinks down, it takes place in fluids liquids and gases. For eg. boiling of water. 3) RADIATION- The process of tranfer of heat in which heat is transmitted, radiated and absorbed in case of a body, no medium necessarily required in this process but it can also take place in or through a body. For eg. the sun's rays (light).

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Vikash Kumar 6 years, 3 months ago

Conduction radiation convection

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Arpita Singh 6 years, 3 months ago

Three ways conduction . Convection ,Radiation

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Shashank Shekhar 6 years, 3 months ago

Conduction ,convection and radiation

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Ayushi Dwivedi Ayushi Dwivedi 6 years, 3 months ago

Radiation

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..... is the mode of transfer of heat where no medium is required

Posted by Ayushi Dwivedi Ayushi Dwivedi 6 years, 3 months ago

CBSE > Class 07 > Science

6 answers

Pallavi Mansingh 6 years, 3 months ago

Radiation

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Vikash Kumar 6 years, 3 months ago

Radiation

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Tanya Gupta 6 years, 3 months ago

Radiation

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Arpita Singh 6 years, 3 months ago

Radiation

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Aradhana Pai 6 years, 3 months ago

Radiation

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Vimal Kumar 6 years, 3 months ago

A mode of transfer of heat in a material from one end to the another without the movement of particles is called cond a mode of transfer of heat in which particles do not move but the heat is transfer without the use of medium is it is a process called radiation uction and

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What is the difference between cell and battery

Posted by Shanthiya Ravichandran 6 years, 3 months ago

CBSE > Class 07 > Science

2 answers

Kanish Sharma 6 years, 3 months ago

Cell is smaller than battery

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Aradhana Pai 6 years, 3 months ago

Cell has only one positive and one negative side while a battery has two or more cells connected to one another.

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Sea breeze blows during

Posted by Subasini Devi 6 years, 3 months ago

CBSE > Class 07 > Science

6 answers

Pallavi Mansingh 6 years, 3 months ago

Sea breezes are formed by water, they are weaker breezes and have moisturous winds and are formed during daytime.

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Swayam Gupta 6 years, 3 months ago

Sea breeze blows during day time

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Arpita Singh 6 years, 3 months ago

Day

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Shashank Shekhar 6 years, 3 months ago

Sea breeze happen during daytime

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Anisha Sharma 6 years, 3 months ago

Day

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Subasini Devi 6 years, 3 months ago

At NIGHT

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No medium is required for transfer of heat by process of

Posted by Subasini Devi 6 years, 3 months ago

CBSE > Class 07 > Science

7 answers

Pallavi Mansingh 6 years, 3 months ago

Radiation

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Vikash Kumar 6 years, 3 months ago

Radiation

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Vinod Kumar Vinod Kumar 6 years, 3 months ago

Radiation

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Tanya Gupta 6 years, 3 months ago

Radiation

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Kanish Sharma 6 years, 3 months ago

Radition

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Prajwal Pandey 6 years, 3 months ago

Radiation

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Krutika Kadam 6 years, 3 months ago

Radiation

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Land brreeze blows during

Posted by Subasini Devi 6 years, 3 months ago

CBSE > Class 07 > Science

9 answers

Pallavi Mansingh 6 years, 3 months ago

Land breezes are formed by land, they are stronger breezes and have dry winds and are formed at nights.

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Swayam Gupta 6 years, 3 months ago

Land breeze blows at NIGHT

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Tanya Gupta 6 years, 3 months ago

Night

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Arpita Singh 6 years, 3 months ago

Night

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Shashank Shekhar 6 years, 3 months ago

Night time

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Anisha Sharma 6 years, 3 months ago

Night

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Kanish Sharma 6 years, 3 months ago

Night

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Prajwal Pandey 6 years, 3 months ago

Night time

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Subasini Devi 6 years, 3 months ago

Day

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Ozone acts as a natural shield against the suns radiation justify?

Posted by Nipun Thakare 6 years, 3 months ago

CBSE > Class 07 > Science

1 answers

Aradhana Pai 6 years, 3 months ago

Ozone (O3 or trioxygen) layer present in high amounts in the stratosphere protects us from the harmful ultaviolet rays by absorbing them. UV rays can be very harmful to the skin and the eyes as it can cause serious problems like burning sensation in the cornea of the eyes and other medical issues .

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Define land breeze and sea breeze.

Posted by Aradhana Pai 6 years, 3 months ago

CBSE > Class 07 > Science

2 answers

Kena Gandhi 6 years, 3 months ago

When aur moves from sea to land is called land breeze. The cool air from land to sea is called sea breeze

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Subasini Devi 6 years, 3 months ago

When cool air from land moves to sea is called land breeze The air from the sea is called sea breeze

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Bile is stored where

Posted by Reena Devi 6 years, 3 months ago

CBSE > Class 07 > Science

12 answers

Pallavi Mansingh 6 years, 3 months ago

Bile is a digestive juice which is secreated by the liver and is temporarily stored in the the gall bladder.

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Kishlay T 6 years, 3 months ago

Gall bladder

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Aishwarya Gupta 6 years, 3 months ago

Gall bladder

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Kena Gandhi 6 years, 3 months ago

In gall bladder

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Vinod Kumar Vinod Kumar 6 years, 3 months ago

Gall bladder

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Arpita Singh 6 years, 3 months ago

Gall bladder

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Prajwal Pandey 6 years, 3 months ago

Gall bladder

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Om Prakash 6 years, 3 months ago

Gall bladder

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Nipun Thakare 6 years, 3 months ago

In gall blader near liver.

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Manya Jhamb 6 years, 3 months ago

Gall bladder

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Savita Jha 6 years, 3 months ago

Gall bladder

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.. ... 6 years, 3 months ago

Gall bladder

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Why can get distorted by the pressure when it is boiled and caped?what is the frequency of the pressure if it is crushed in 5sec

Posted by Hebina Sinha 6 years, 3 months ago

CBSE > Class 07 > Science

1 answers

.. ... 6 years, 3 months ago

Increasing pressure usually increases the boiling point of a liquid. A way to think about it is that the molecules of the liquid need more energy to break into the gas phase when the more molecules are hitting the surface of the liquid with more energy. For melting point, increasing the pressure makes some difference.

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Give two units which are greater than the si unit

Posted by Vidita Agarwal 6 years, 3 months ago

CBSE > Class 07 > Science

2 answers

Jasvinder Kaur 6 years, 3 months ago

Kilojoule and joule OR kj and j 1 kilojoule = 1000 joule OR 1 kj = 1000 j

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.. ... 6 years, 3 months ago

tonne, megagram are two units of mass which are bigger than the si unit of mass

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Why intestinal juice is very important for digestion

Posted by Moin Khan 6 years, 3 months ago

CBSE > Class 07 > Science

2 answers

Pallavi Mansingh 6 years, 3 months ago

They are important for digestion as they carry out 90% of the digestion of the nuetrients it also helps in the absorbtion of nutrients and minerals from the food before the last process of digestion egestion or the excreation of the undigested food.

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Sagar Vithalkar 6 years, 3 months ago

Bile juice

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What are the reasons of vomiting?

Posted by Imran Khan 6 years, 3 months ago

CBSE > Class 07 > Science

2 answers

Pallavi Mansingh 6 years, 3 months ago

Sometimes when we eat outside food which is not recognised by the taste buds and the stomach or we do overeating the food which is swallowed is not accepted or is rejected by the stomach and is unwanted, it returns to the mouth and as a result we have vomitting sensation which leads to vomitting or the excreation of the unwanted food particles by the stomach directly taken out through the mouth.

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Sagar Vithalkar 6 years, 3 months ago

Because that food is rejected by the body

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