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How does efficiency of nutrients affect the crop?

Posted by Chetna Narula 7 years, 2 months ago

1 answers

Rahul Dubey 7 years, 2 months ago

Plant requires 16 elements for their growth.These includes macronutrients and micronutrients.Nitrogen,phosphorous and potassium are some macronutrients

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Give points of difference between egg producing chicken and boiler producing chicken

Posted by Chetna Narula 7 years, 2 months ago

CBSE > Class 09 > Science

0 answers

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What are the different ways of hybridization

Posted by Chetna Narula 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 2 months ago

Hybridization is the process of mixing different species or varieties genetically to produce hybrids with new characteristics.
Types of hybridization:
1) Intervarietal hybridization: In this two parents from the same species are crossed.
2) Distant hybridization : This includes intergeneric or interspecific that is parents belonging to different genus or species respectively.

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Write a short note on malaria as a disease , its symptoms and control

Posted by Chetna Narula 7 years, 2 months ago

CBSE > Class 09 > Science

0 answers

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What are baic conditions of good health ?

Posted by Chetna Narula 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Omkara Ghandwani 7 years, 2 months ago

The basic conditions for good health are the person ? should be mentally, physically and socially fit

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Give function of antibiotic penicillin

Posted by Chetna Narula 7 years, 2 months ago

CBSE > Class 09 > Science

2 answers

Rahul Dubey 7 years, 2 months ago

It prohibit thr growth of bacteria inside the human body.

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Ashlok Kumar 7 years, 2 months ago

Antibiotic penicillin destroy the cell wall of the bacteria

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Deffiency of vitamin d

Posted by Abhishek Kumar 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Abhishek Kumar 7 years, 2 months ago

Rickets

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Describe plathyhelminthes. Write it's features in point?

Posted by Aadhi Cc 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Sayahnika Mishra 7 years, 2 months ago

1:- They are bilaterally symmetrical and triploblastic 2:- They do not have true body cavity or coelom in which well developed organs can be accommodated 3:- They are dorsiventrally meaning flatttened. That is why they are called flatworms. 4:- They are either free -living or parasitic . 5:- Eg:- planaria and liverflukes

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hye guys my xam is going on nd my next xam is science so plz anyone tell me from where i practice the numericals of ch work ,energy

Posted by Sangita???? Ankita 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Insha Naseem 7 years, 2 months ago

U like

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Define pisces.write it's features in points?

Posted by Aadhi Cc 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 2 months ago

The main features of Pisces are:

They are exclusively water living animals and include the fishes.
Their skin is covered with scales/plates.
They obtain oxygen dissolved in water by using gills.
Their body is streamlined, and a muscular tail is used for movement.
They are cold-blooded and their hearts have only two chambers.
They lay eggs.

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Suggest what kind of motion is represented by graph

Posted by Alka Sahni 7 years, 2 months ago

CBSE > Class 09 > Science

0 answers

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activity depend on inertia of motion

Posted by Himanshu Maurya 7 years, 2 months ago

CBSE > Class 09 > Science

0 answers

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What produces more serve burns boiling water or stream

Posted by Krishna Joshi 7 years, 2 months ago

CBSE > Class 09 > Science

2 answers

Yogita Ingle 7 years, 2 months ago

Steam contains more heat, in the form of latent heat, than boiling water. So when steam comes in contact with skin it gives out 22.5 X 10⁵ joules per kilogram more heat than boiling water, so steam causes more severe burns.

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Kumkum Sarswat 7 years, 2 months ago

Steam because it has absorbed extra latent heat of vaporisation

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What is variation of acceleration due to gravity?

Posted by Mantasha Khan 7 years, 2 months ago

CBSE > Class 09 > Science

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A car starts from rest and attains a velocity of 10m/sec. in 40 sec. The driver applies brakes and slows down the car to 5m/sec. Find the acceleration of the car in both the cases.

Posted by Sriti Sharma 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Ram Kushwah 7 years, 2 months ago

u=0,v=10,t=40 s

v=u+at

10=0+40a

a=10/40=0.25 m/s²

Again u=10,v=5 t=10 s

v=u+at

5=10+10a

-5=10a

a=-0.5 m/s2

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When we cry why tears come from our eyes

Posted by Babi Sahoo 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Abcd 1234 7 years, 2 months ago

‌‍‌‌‍‍‌‌it is the nervous system of us .

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What is the difference between atoms and molecules

Posted by Sumn Kkr 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Jatin Sharma 7 years, 2 months ago

1.Atoms r highly reactive whereas molecules r comparatively reactive..... 2. Atoms may or may not exist in free state whereas molecules exist in free state 3. Atoms r comprise of nucleus and electron whereas compound r comprise of two or more atoms.... 4. Atoms have nuclear bond whereas molecules r covalent bond.... 5. Atoms means the tiny particles of chemical element which may or may no exist independently whereas molecules are set of atoms held together by bond

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Is ice at 273 Kelvin is effective in cooling than water at same temperature

Posted by Aarzoo Sharma 7 years, 2 months ago

CBSE > Class 09 > Science

2 answers

Arjun Bhatty 7 years, 2 months ago

I mean yes

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Arjun Bhatty 7 years, 2 months ago

No, ice is more effective as it has less latent heat than water at same temperature

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What is countable disease

Posted by Rashmi Shil 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Rashmi Shil 7 years, 2 months ago

The disease spread one person to another person

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A racing car has a uniform acceleration of 4 m/s2.what distance will it cover in 10 second after start?

Posted by Saniya Pathan 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 2 months ago

Here, acceleration, a = 4 m/s²
initial velocity, u = 0
Distance covered, s = ?
time taken = 10 s
We know, S = ut + 1/2 at²
= 0(10) + 1/2 (4) (10)²
= 2 (100)
= 200m

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Write the electronic configuration of first 20 element

Posted by Rajat Jain 7 years, 2 months ago

CBSE > Class 09 > Science

0 answers

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Calculate the no. Of aluminium ions present in 0.051g of aluminium oxide

Posted by Ashwani Kumar 7 years, 2 months ago

CBSE > Class 09 > Science

0 answers

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What is the atomic mass of argon

Posted by Sneha Sneha 7 years, 2 months ago

CBSE > Class 09 > Science

2 answers

Yogita Ingle 7 years, 2 months ago

Atomic number of Argon is : 18
It is an inert gas.
Atomic mass of Argon is: 39.9 amu

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Arjun Bhatty 7 years, 2 months ago

It is 40

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Plant cell shrink when kept in hypertonic solution why?

Posted by Sahilpreet Singh 7 years, 2 months ago

CBSE > Class 09 > Science

4 answers

Ashlok Kumar 7 years, 2 months ago

Plant cell will not shrink because of the presence of the cell wall.

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Yogita Ingle 7 years, 2 months ago

As osmosis is the passive movement of water from the region of higher water concentration to the region of lower water concentration ,and in hypertonic solution the surrounding medium is concentrated(here the concentration is of the substance present outside the cell)and that means water is less therefore water comes out through osmosis from the cell in order to qualize he concentration.

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Arjun Bhatty 7 years, 2 months ago

This is because exosmosis takes place, which means the water moves out of the cell

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Abhi Gupta 7 years, 2 months ago

I don't no

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If a car move with velocity 10m/s and after 20sec its speed 30m/s ,what will be the acceleration and displacement

Posted by Shivam Shukla 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Arjun Bhatty 7 years, 2 months ago

a=v-u/t. =30-10/20. =20/20. =1m/s^2

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a sheet of paper and a stone was dropped from the first floor of a building together which to the two will reach the ground first and why

Posted by Ankush Ankush 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Arjun Bhatty 7 years, 2 months ago

The stone will reach first because it has a smaller surface area, so the pressure will be more (pressure is inversely proportional to area).

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If the organisation of a cell is destroyed due to some physical or chemical influence, what will happen?

Posted by Mahesh . 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Arjun Bhatty 7 years, 2 months ago

The lysosomes will burst and will release their digestive enzymes and digest the cell

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Give two examples of molecules having one kind of atom only

Posted by Rishabh Bajaj 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Arjun Bhatty 7 years, 2 months ago

Gold molecule and oxygen molecule

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Distinguish between angiosperms and Gymnosperms?

Posted by Aadhi Cc 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Gaurav Seth 7 years, 2 months ago

Angiosperms are seed producing flowering plants whose seeds are enclosed in the ovary whereas Gymnosperms are seed producing non-flowering plants whose seeds are naked.Angiosperms are seasonal whereas Gymnosperms are evergreen.Angiosperms possess flowers which enclose the reproductive structures whereas in Gymnosperms the reproductive structures are present in cones. Angiospermic flowers can be unisexual or bisexual but Gymnospermiccones are unisexual. Angiospermspossess cotyledons whereas Gymnosperms do not have cotyledons.Seeds are enclosed inside the ovary that is a fruit in Angiosperms whereas seeds in Gymnosperms are bare found on cones. Wood is hard in Angiospermswhereas wood is soft in Gymnosperms.Angiosperms are non-perennial whereas Gymnosperms are perennial.

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What are features of phylem vertebrata?

Posted by Aadhi Cc 7 years, 2 months ago

CBSE > Class 09 > Science