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What is cell sap

Posted by Ishaan Dave 7 years, 1 month ago

1 answers

Vivansh Pandey 7 years, 1 month ago

Cell sap is the fluid present inside the large vacuoles of the cell. It comprises of sugars, salts amino acids and mainly water. It provides buoyancy and support to the cell. It also helps in storage of many materials Cell sap maintains osmosis of the cell. It also helps in colouration due dissolved pigments in it.

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5 marks question in diversity in living organisms? Please

Posted by Kartik Shukla 7 years, 1 month ago

CBSE > Class 09 > Science

3 answers

Jai Prakash 7 years, 1 month ago

Write 5 differentation between amphibians and aves?with examples.

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Manmeet Singh 7 years, 1 month ago

What are the advantages of classification organisms

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Suraj Kumar 7 years, 1 month ago

1)What are the characteristics of kindom fungi? This had already came in my previous exam. 2)Differance between chordata and non chordata. And this is another important 5 marks question.

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Difference between suspension and colloids

Posted by Adnan Ansari 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Yogita Ingle 7 years, 1 month ago

Suspension	Colloid
It is a form of homogeneous solution	It is a form of heterogeneous solution
Particle size greater than 1000 nm	Particle size range from 1-1000 nm
Particles settle down well	Particles do not separate
Can be separated by filtration	Cannot be separated by filtration
May scatter light	Shows Tyndall effect (scatters light)
Opaque	Translucent
Easily visible through naked eye	Not visible through naked eye

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Suraj Kumar 7 years, 1 month ago

In suspension the size of particles are larger than colloids and can be seen with naked eyes and particles do not pass through filter paper. But in colloid particles are smaller and passes through filter paper and cannot be seen even with microscope.

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How many molecules of water of hydration are present in 630mg of oxalic acid?

Posted by Priyanshu Prakash 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Priyanshu Prakash 7 years, 1 month ago

6.022*10*21

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Yogita Ingle 5 years, 11 months ago

Number of molecules available in oxalic acid is equal to 630 divided by 126 which come to 5.

Number of molecules of water present is equal to 5 x 6.02 x 10²³

Therefore, number of molecules of water of hydration present in 630 mg oxalic acid is 30.1 x 10²³.

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What is tindal effect??

Posted by Drishi Jain 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 1 month ago

This scattering of a beam of light by the particles of a colloid is called the Tyndall effect. When we apply torch light on a galss of milk then the path of the light becomes visible but it is not so in case of water because in milk light is scattered by its very fine particles.
Tyndall effect can be observed when sunlight passes through the canopy of a dense forest. In the forest, mist contains tiny droplets of water, which act as particles of colloid dispersed in air.

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What is formula of sodiun oxylate and ferrous acetate

Posted by Samarth Varshney 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 1 month ago

Sodium oxalate, or disodium oxalate, is the sodium salt of oxalic acid with the formula Na₂C₂O₄. It is a white, crystalline, odorless solid, that decomposes above 290 °C.
Ferric acetate is the coordination compound more commonly known as "basic iron acetate". With the formula [Fe₃O(OAc)₆(H₂O)₃]OAc it is a salt,

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Difference between suspension and colloidal sotution

Posted by Tanu Chandravanshi 4 years, 9 months ago

CBSE > Class 09 > Science

1 answers

Sia ? 4 years, 9 months ago

Suspensions - Suspension is a heterogeneous mixture in which particle size of one or more components is greater than 1000nm. When mud is dissolved in water and stirred vigorously, particles of mud are distributed evenly in water. After some time, the particles of this solution settle under water due to influence of gravity. This solution is an example of Suspension (see picture below). Contrary to True Solution, particles of suspension are big enough to be seen with naked eye.
Colloidal Solution - Colloidal Solution is a heterogeneous mixture in which particle size of substance is intermediate of true solution and suspension i.e. between 1-1000 nm. Smoke from a fire is example of colloidal system in which tiny particles of solid float in air. Just like true solutions, Colloidal particles are small enough and cannot be seen through naked eye. They easily pass through filter paper. But colloidal particles are big enough to be blocked by parchment paper or animal membrane.

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Difference between solid ,liquid and gas

Posted by Tanu Chandravanshi 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 1 month ago

Solids	Liquids	Gases
Highly Strong intermolecular forces between the molecules, leads to a definite volume in Solids.	The intermolecular forces are stronger than gases but weaker than solids.	The intermolecular forces are practically non existent. Thus, there is no definite volume.
Solids have a definite shape to them.	Liquids do not have a definite shape.	Gases do not have a definite shape.
The intermolecular space between solids is absent.	The intermolecular space is moderate but present.	The intermolecular space is free flowing and plenty.
The force of attraction between the molecules is incredibly high.	The force of attraction between molecules is pretty moderate.	There is no intermolecular force of attraction between the molecules.
They are incompressible.	Liquids cannot be compressed.	Gases can be compressed quite easily.

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If a bus accelerates uniformly from rest and attains a speed of 20 ms in 10 seconds then . Calculate a distance travel

Posted by Manisha Mali 7 years, 1 month ago

CBSE > Class 09 > Science

3 answers

Sharad Sharma 7 years, 1 month ago

Distance = speed×time 20×10=200m

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Harsh Dagar 7 years, 1 month ago

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Farhaan Fahi 7 years, 1 month ago

10m

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The speed of certain waves depends on the medium . 1 .What kind of waves are they? 2. Give two kind of such waves and give one difference between them. Give one example of each. Please answer my question.

Posted by Pratyusha Samantaray 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Sharad Sharma 7 years, 1 month ago

Solid,liquid and gas 1•longitudinal and transverse waves 2•longitudinal waves particle vibrate back and forth in same direction. Transverse waves particle vi rate up and down at right angles longitudinal waves example guitar waves transverse waves example waves in water

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What are canal rays? (ch. 4) Plz help... ?

Posted by Arav Fernandez 7 years, 1 month ago

CBSE > Class 09 > Science

3 answers

Manani Chaudhary 7 years, 1 month ago

Actually anode rays known as canal rays because anode rays passes through the canals or holes of the cathode that is why they are also called canal rays

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Yogita Ingle 7 years, 1 month ago

Canal rays are positively charged radiations. These rays consist of positively charged particles known as protons. They were discovered by Goldstein in 1886.

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Pratyusha Samantaray 7 years, 1 month ago

Positively charged radiations in a gas discharge is called canal rays

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Calculate the number of atoms in 6g of methane?

Posted by The Invincible Tech 7 years, 1 month ago

CBSE > Class 09 > Science

0 answers

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A sound wave has a frenquency 2hz and wave length 40 cm. How long will it take to travel 1.6 km

Posted by Aanchal Yadav 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Pankaj Singh 7 years, 1 month ago

V=f× wavelength V = 2×0.4=0.8m/sec Speed=distance÷time 0.8 = 1600÷time Time = 1600÷0.8 =20sec

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Hipresh Biswal 7 years, 1 month ago

Frequency=2hz Wavelength=40cm=0.40m We know that speed = wavelength× frequency =0.40×2hz=0.8m/s The time taken by the wave to travel a distance ,d= 1.6km is t=d/v= 1.6× 1000 m/0.8m=2s

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If valemcy is 3 what is its chemical formula

Posted by Kaushikee Bhatt 7 years, 1 month ago

CBSE > Class 09 > Science

0 answers

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Differentiate the stature of niclce

Posted by Suraj Kumar 7 years, 1 month ago

CBSE > Class 09 > Science

0 answers

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3 human activity which are responsible for depletion of Ozone layer

Posted by Rahul Jha 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Simran Das 7 years, 1 month ago

Production of CFC, introduction of more automobiles, burning of fuels..... are the three human activity which are responsible for depletion of Ozone layer.

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Why CO2 is known as dry ice

Posted by Umesh Verma 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Simran Das 7 years, 1 month ago

When co2 is is being kept under high pressure of 1atmosphere and low temperature, changes to ice. this ice when kept in our hands, it does not wet our hands so carbon dioxide is also known as dry ice.

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Vandana Sharma 7 years, 1 month ago

Carbon dioxide gas turns to dry ice when the temperature drops to -110 degree F that'sright !110 degrees BELOW zero! when dry ice is warmed above -110 degree F it changes from solid dry ice straight back to carbon dioxide gas,since it never passes through the liquid phase its called dry ice.

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What is the function of lymph

Posted by Rahul Jha 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Vandana Sharma 7 years, 1 month ago

Function of lymph 1) lymph acts as a middle man which transport oxygen food materials ,hormones ,etc,to the body cells 2) and brings carbon dioxide and other metobolic wastes,from the body cells to blood and then finally pours the same into the venous system 3) body cels are kept moist by the lymph

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What is biochemical cycle?how cycling of nutrients take place in the atmosphere

Posted by Bijay Kumar Singh 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Rahul Jha 7 years, 1 month ago

the repeated circulation of biogenic Nutrition between abiotic and biotic component of the biosphere is known as biochemical cycle

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Why atom natural

Posted by Aryan Kumar 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Saurav Kumar 7 years, 1 month ago

Atoms are electrically neutral because they contain equal quantities of positively charged protons and negatively charged electrons. Electrons and protons have equal but opposite charges, so the result is no net charge. Ions are atoms that have gained or lost electrons.

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Why are antibiotics not effective for viral disease

Posted by Rahul Jha 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Harsh Dagar 7 years, 1 month ago

Continuing answer-and antibiotics block biochemical pathways in which bacteria cell wall cannot be formed but viruses flow without having cell wall

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Deepika Sengar 7 years, 1 month ago

Because virus do not their own mechanism they use our cell as an host

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Hey friends..... what r ur views about cellular memory..

Posted by Palak ?? 7 years, 1 month ago

CBSE > Class 09 > Science

0 answers

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What is the scientific name of cauliflower?????

Posted by Palak ?? 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Neya Saji 7 years, 1 month ago

Brassica Oleracea Vas.botrytis?

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What are the features of cell of parenchyma

Posted by Alok Ray 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Akanksha Kumari? 7 years, 1 month ago

1. They are living cells. 2. They have intercellular space between them. 3. They contain small nucleus and large vacuoles. 4. They often contain cytoplasm. 5. They are oval, elongated or round in shape.

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Mohd Ali 7 years, 1 month ago

Storage of food in form of starch Mechanical support Isodiametric cell

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What are 3 laws of motion

Posted by Atul Kuwar 7 years, 1 month ago

CBSE > Class 09 > Science

4 answers

Sharad Sharma 7 years, 1 month ago

First law. If the object is in motion or rest it will continue in the same state unless any externalforce is provided Second law. Force directly change in momentum upon time taken. Third law. Every action has equal and opposite reaction

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Bhawna Sharma 7 years, 1 month ago

3rd law :- it states that every action has an equal and opposite reaction

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Harsh Pahwa 7 years, 1 month ago

First law-:every object stays in state of rest or uniform motion until or unless some external force Is applied on object Second law -:the rate of change of momentum is directly proportional to unbalanced force applied over an object and the object moves in direction of unbalanced force acting over an object Third law -:on any object action and reaction are two equal and opposite forces

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Palak ?? 7 years, 1 month ago

First law: an object will continue to be in the state of rest or in uniform motion until and unless and unbalanced force is applied on it it is now also known as Law of Inertia Second law: the rate of change of momentum is directly proportional to the force applied in the direction of force Third law: to every action there is an equal and opposite reaction

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Who has invented a cell

Posted by Atul Kuwar 7 years, 1 month ago

CBSE > Class 09 > Science

4 answers

Vivansh Pandey 7 years, 1 month ago

Cell was first discovered by Robert Hooke in 1665. He first observes the bark of a tree, and in a bark he founded some cells meaning, 'small room'.

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Mohd Ali 7 years, 1 month ago

Cell was 1st discovered by Robert Hooke

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Akanksha Kumari? 7 years, 1 month ago

Cell was discovered by Robert Hook in 1665.

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Palak ?? 7 years, 1 month ago

Cell was discovered.....not invented....it was in existence by nature

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What are convention currents

Posted by Riya Gupta 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Vivansh Pandey 7 years, 1 month ago

A convection current is a process which involves the movement of energy from one place to another. It is also called to as convection heat transfer. What is the reason that makes you feel hotter when placing hands above a campfire or when sitting next to it? Or, why is the movement of liquid so rapid when water is boiled in a pot? These things happen as a result of the Convection Currents.

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What is biogeochemicalcycle?

Posted by Atul Kuwar 7 years, 1 month ago

CBSE > Class 09 > Science