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Red blood cells

Posted by Swayam Modanwal 7 years, 3 months ago

1 answers

Yogita Ingle 7 years, 3 months ago

The Red blood cells are also called to as erythrocytes. These RBC’s store the hemoglobin in them which is a respiratory pigment binding to oxygen or the carbon dioxide. This helps in the movement of the oxygen to different tissues and organs of the human body by taking away the carbon-dioxide. Hemoglobin mainly comprises of iron which combines with the oxygen, thus giving the reddish color to the blood. The main functions of the RBCs are the transportation of nutrients and the hormones throughout the human body.

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What is liquid pressure ?

Posted by Sriram Kiran 7 years, 3 months ago

CBSE > Class 08 > Science

1 answers

Yogita Ingle 7 years, 3 months ago

The pressure exerted by the liquid in a vessel is called liquid pressure. The pressure exerted by a liquid changes with depth in the liquid. The pressure exerted by a liquid increases with increasing depth inside the liquid. The pressure exerted by a liquid is small just under the surface of the liquid. But as we go we deeper in a liquid the pressure of liquid increases.As the depth of liquid increases the weight of liquid column pushing down from above increases and hence the pressure also increases.

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difference between combustion and flame

Posted by Vedant Chorge 7 years, 3 months ago

CBSE > Class 08 > Science

1 answers

Yogita Ingle 7 years, 3 months ago

The oxidation reaction in which high amount of heat is produced called as combustion.

The combustion reaction during which flame is produced along with heat is called as burning.

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What is the diffrence between atmospheric preassure and non contact forces

Posted by Anurag Sharma 7 years, 3 months ago

CBSE > Class 08 > Science

1 answers

Yogita Ingle 7 years, 3 months ago

Non-Contact Forces: The types of forces that can be exerted without requiring any contact with any object are ‘non-contact forces’.
Atmospheric pressure is the air pressure which is exerted by the weight of air present in the atmosphere. Atmospheric pressure is due to the weight of air present in the atmosphere above us.Atmospheric pressure also acts in all directions.

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What are photosensitive cell

Posted by Ananthu Ananthu 7 years, 3 months ago

CBSE > Class 08 > Science

1 answers

Meghna Thapar 5 years, 7 months ago

Photosensitive cells called rods and cones in the retina convert incident light energy into signals that are carried to the brain by the optic nerve. In the middle of the retina is a small dimple called the fovea or fovea centralis. ... The human eye contains two kinds of photoreceptor cells; rods and cones. The macula lutea, also called fovea, contains a very high concentration of cones. These are the light-sensitive cells in the retina that give detailed central vision.

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what are the advantages of recycling paper? why is it portant?

Posted by Preeti Nakwal 7 years, 3 months ago

CBSE > Class 08 > Science

1 answers

Yogita Ingle 7 years, 3 months ago

Recycling Paper helps the environment.
Recycling paper is economically responsible.
Recycling reduces waste and improves efficiency.
Recycling promotes a clean, green image.
Recycling paper produces jobs.

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how Microorganism be both friend and foe?

Posted by Vedant Chorge 7 years, 3 months ago

CBSE > Class 08 > Science

3 answers

Sonali Aggarwal 7 years, 3 months ago

The main microorganisms in and on our bodies are protozoa, algae, fungi, bacteria and viruses. Most microorganisms are beneficial, for example, there are microorganisms in our large intestine that synthesise vitamins and allow them to be absorbed into the bloodstream. However, a tiny minority are pathogens (disease-causing agents). These pathogens, often called germs or bugs, are a threat to all life forms.

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Siri Moola 7 years, 3 months ago

Microorganisms help in many ways like they are used in bakery. And in vaccines. But they also cause diseases and spoil food, leather and clothing. So, they are both friend and foe

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Anvi Puri 7 years, 3 months ago

Because some microorganisms are useful like for creating many antibiotics , tanning of leather , penicillin is obtained from them , they help in curdling of milk and in various industrial purposes whereas they can be harmful as they can destruction to fields,crops and cause diseases to humans

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Sound can pass trough solid liquid and gas

Posted by Sanskar Sahu 7 years, 3 months ago

CBSE > Class 08 > Science

1 answers

Shreya Prajapati 7 years, 3 months ago

Yes!!!!

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What is combusion

Posted by Mahak Vaishnav 7 years, 3 months ago

CBSE > Class 08 > Science

1 answers

Yogita Ingle 7 years, 3 months ago

The chemical process in which a substance reacts with oxygen to give off heat is called combustion. Substancec which undergoes combustion are called a combustible substances or a <a href="https://www.learnnext.com/nextgurukul/wiki/concept/CBSE/VIII/Science/Fuel.htm" target="_blank">fuels</a>.
Example: LPG, kerosene, petrol...etc

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when a magnet is cuted in two peices then how north or south create in its end?

Posted by Dhruv Sharma 7 years, 3 months ago

CBSE > Class 08 > Science

1 answers

Nishu Singh 7 years, 3 months ago

Because unlike poles of magnet are attract with each other

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व्हाट अरे बैक्टीरिया

Posted by Jainam Shah 7 years, 3 months ago

CBSE > Class 08 > Science

1 answers

Shreya Sengar 7 years, 3 months ago

Why are you not writting the correct question.

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How do weeds affect the growth of crops

Posted by Rishikesh Mankar 7 years, 3 months ago

CBSE > Class 08 > Science

6 answers

Nishu Singh 7 years, 3 months ago

The weeds take sun light ,nutrients and space of crops .

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Prabir Rout 7 years, 3 months ago

By taking the important nutrient needed by the crop plant

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Ritesh Gahlot 7 years, 3 months ago

Weeds are harmful that automatically and harm them by taking their water, sunlight etc and it can be removed by weedicites and pesticites

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Guru Priyaa 7 years, 3 months ago

Weeding is necessary since weeds compete with the crop plants for water,nutrients,space and light. Thus, thay affect the growth of the crop. Some weeds interfere even in harvesting and may be poisonous for animals and human beings.

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Yogita Ingle 7 years, 3 months ago

Weeds are the unwanted plants that compete with the crop plants for nutrition and various other factors. Thus, they damage crops by affecting their growth. Weeds compete with the main crop plant for air, water ,sunlight and nutrients in the soil making them deficient for the main crop. Also, they are not of use to humans. Thus they affect the growth of the plant and their removal is necessary.

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Jainam Shah 7 years, 3 months ago

They affect the plant by absorbing their nutrients

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explain the force of gravity

Posted by Roma Mittal 7 years, 3 months ago

CBSE > Class 08 > Science

2 answers

Golam Maroof Ahmed 7 years, 3 months ago

The natural phenomenon of attraction between physical objects with mass or energy; the weakest of the four fundamental forces of nature. Also called gravity.

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Yogita Ingle 7 years, 3 months ago

Force exerted by earth, moon, sun and other planets is called gravitational force. Earth attracts all objects towards it. Similarly, all other planets along with moon attract all objects towards them. Since, earth attracts all objects even without coming in contact, thus gravitational force is a non-contact force.

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Name two man-made substance two natural and two natural and two exhaustible substance

Posted by Roma Mittal 7 years, 3 months ago

CBSE > Class 08 > Science

2 answers

Yogita Ingle 7 years, 3 months ago

Natural substance: coal, petroleum, air, water, soil, etc.
Man made: table, chair
Exhaustible substance: coal, petroleum, minerals, etc.

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Golam Maroof Ahmed 7 years, 3 months ago

Man made: schools and bridges Natural made: air and water Exhaustible :coal and petroleum

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How global warming takes place??

Posted by Daljit Singh 7 years, 3 months ago

CBSE > Class 08 > Science

1 answers

Yogita Ingle 7 years, 3 months ago

With the approach of Industrial revolutions, the use of chemicals in the factories has increased to a dangerous amount. Along with it, deforestation due to industrial or economic purposes and the excess burning of fossil fuels like natural gas, oil, and coal, has increased the concentration of atmospheric carbon dioxide from 315 ppmv (part per million by volume) to about 363 ppmv since 1958. These are some of the primary reasons for which the heat gets trapped in the atmosphere thus causing global warming.

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How deforestation leads to a decrease in a water holding capacity of the soil?

Posted by Abhipsha Sahoo? 7 years, 3 months ago

CBSE > Class 08 > Science

1 answers

Ritesh Varma 7 years, 3 months ago

Is deforestation occurs in a particular area, so there are no trees and plants to hold the soil, then when the high rainfall occurs so, there are no trees to hold the soil. So, this is why deforestation leads to a decrease in a water holding capacity of soil.

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How drought will occur?

Posted by Purv Tamk 7 years, 3 months ago

CBSE > Class 08 > Science

2 answers

Tejas Nv 7 years, 3 months ago

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Yogita Ingle 7 years, 3 months ago

Droughts are the conditions which involve abnormally long period of insufficient or no rainfall.

Droughts are caused due to lack of rains.
Drought condition results in drying up of wells, lakes, ponds and thereby creating water scarcity.
Droughts result in forest fires caused by enormous amount of heat from scorching sun.

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What is meant my algae

Posted by Dharani Shree 7 years, 3 months ago

CBSE > Class 08 > Science

2 answers

Nishu Singh 7 years, 3 months ago

Algae is a microorganism.it is a green plant.

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Yogita Ingle 7 years, 3 months ago

Algae: Algae are green plants which are simple in structure. A cell of algae contains cell wall and chloroplast. Algae are autotrophs. Some algae are microscopic. Examples: Chlamydomonas, Spirogyra, etc.

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What is quatam mechanics

Posted by Elizabeth Lawrence 7 years, 3 months ago

CBSE > Class 08 > Science

1 answers

Yogita Ingle 7 years, 3 months ago

Quantum mechanics is the branch of physics that deals with the behaviour of matter and light on a subatomic and atomic level. It attempts to explain the properties of atoms and molecules and their fundamental particles like protons, neutrons, electrons, gluons and quarks.

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Can newton be kept in fraction?

Posted by Suramya Banerjee 7 years, 3 months ago

CBSE > Class 08 > Science

0 answers

ANSWER

Why gravity pull towards earth

Posted by Sarvesh Saravanan 7 years, 3 months ago

CBSE > Class 08 > Science

4 answers

Golam Maroof Ahmed 7 years, 3 months ago

TL;DR: The acceleration caused by Earth (i.e. its gravity) is only dependent on Earth’s mass and the distance between the center of mass of Earth and the center of mass of the thing it’s attracting. The attributes of the thing attracted have nothing to do with it. Longer explanation: Gravity as a force does not act by pulling things *down* - it is an attractive force that pulls things together. In this case, something pulling you towards the Earth is pulling you down because you’ve defined “towards the Earth” as “down”. The force of gravity depends on a few factors - namely, the masses of the object in question and the distance between objects. Technically speaking, you and I have our own gravities as well. But gravity is actually a very weak force - and at the human scale, it’s negligible enough that things don’t get attracted to us visibly. All this is packaged up nicely in an equation known as Newton’s Law of Universal Gravitation, which is often written as F = (G * M1 * M2)/(r²), where M1 and M2 are the masses of the two bodies in question, r is the distance between the center of masses of the two bodies, G is the Gravitational constant, and F is the force acting on both bodies. Now take M1 as the mass of the Earth, M2 as the Mass of your object, a as the acceleration of your object, and bring in Newton’s Second Law of motion: M2 * a = (G * M1 * M2)/(r²) Divide by M2 on either side, and you’ll find that a = (G * M1)/(r²). So the acceleration of any body on the surface of Earth with regards to the Earth is only dependent on the mass of the Earth, and the radius of the Earth. In this case, a = 9.81 = g. :) (For objects like you, which are tiny in comparison to something like Earth, using radius (Earth) for r instead of (radius (Earth) + radius (you)) is a good enough approximation).

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Rock Star 7 years, 3 months ago

It is law of nature gravity means the earth have some power to pull the thing down

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Ashwini Choudhary 7 years, 3 months ago

It is law of nature

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Khushi Gupta 7 years, 3 months ago

It is law of nature

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Whate is the unite of thermameter

Posted by Krishna Pisal 7 years, 3 months ago

CBSE > Class 08 > Science

3 answers

Nishu Singh 7 years, 3 months ago

Celsius

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Ashwini Choudhary 7 years, 3 months ago

Celsius

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Khushi Gupta 7 years, 3 months ago

Celsius

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What are the secondary sexual characters of male and female?

Posted by Secret Superstar 7 years, 3 months ago

CBSE > Class 08 > Science

1 answers

Yogita Ingle 7 years, 3 months ago

Secondary *** characteristics in male

Under the influence of hormones, larynx grows prominently, vocal cords become longer and thicker, causing the voice to become hoarse.
Hair starts growing in the frontal region of the genital area.
Appearance of hair in other areas such as underarms, legs, chest, abdomen, back, and face.
Enlargement of testicles followed by *****.
More secretion of oil from the skin, resulting in the appearance of acne.
Testes grow and start producing sperms.

Secondary *** characteristics in female

Increase in breast size and the darkening of the skin of nipples present at the tips of the breasts.
Appearance of hair in the genital area.
Appearance of hair in other areas such as underarms, face, hands, and legs.
Increase in the size of uterus and ovary.
Beginning of menstrual cycle.
More secretion of oil from the skin, resulting in the appearance of acne.

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Explain the structure of flame in short.

Posted by Deep Odedara 7 years, 3 months ago

CBSE > Class 08 > Science

1 answers

Yogita Ingle 7 years, 3 months ago

There are three zones in flame, viz. outer zone, middle zone and inner zone.
Outer Zone: This zone is blue in colour. It is the hottest part of the flame, because complete combustion takes place in this zone.
Middle Zone: This zone is yellow and orange in colour. This zone is moderately hot because partial combustion takes place in this zone.
Inner Zone: This zone is dark in colour. This is the coolest part of the flame because no combustion takes place in this zone.

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Explain the parts of a candle

Posted by Reyan Dsouza 7 years, 3 months ago

CBSE > Class 08 > Science

2 answers

Ashwini Choudhary 7 years, 3 months ago

There are four parts of candle are 1 luminous-in this zone a blue coloured flame which produces little amount of heat . 2non luminous in this zone a yellow flame which produces heat and appreciable amount of light. 3 dark zone - dark zone around the wick is called inner dark of an combustion. 4 lowest zone- this zone is located at the base of the flame.

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Aman Singh 7 years, 3 months ago

There are four parts of candle are 1 luminous - in this zone a blue coloured flame which produce little amount of heat . 2 non luminous- in this zone a yellow flame which produce heat and appreciable amount of light. 3 dark zone- the dark zone around the wick is called inner dark zone of on combustion. 4 lowest zone - this zone is located at the base of the flame.

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How is the *** of baby determined

Posted by Kartik Bhatnagar 7 years, 3 months ago

CBSE > Class 08 > Science

3 answers

Ashwini Choudhary 7 years, 3 months ago

By the father chromosomes

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Khushi Nain 7 years, 3 months ago

By the father's chromosomes.?

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Reyan Dsouza 7 years, 3 months ago

By the father

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Why we should conserve biodiversity

Posted by Aryan Pembatla 7 years, 3 months ago

CBSE > Class 08 > Science

1 answers

Yogita Ingle 7 years, 3 months ago

Biodiversity, refers to the variety of organisms existing on the earth, their interrelationships and their relationship with the environment. Plants and animals both depend on each other for survival. Thus we need to conserve biodiversity to keep the ecological balance maintained.

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How do we have a baby

Posted by Suraj Dalvi 7 years, 3 months ago

CBSE > Class 08 > Science