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Cells come in different shapes—round, flat, long, star-like, cubed, and even shapeless. Most cells are colorless and see-through. The size of a cell also varies. Some of the smallest are one-celled bacteria, which are too small to see with the naked eye, at 1-millionth of a meter (micrometer) across.

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Birdeep Gumber 5 years, 3 months ago

Robert Hooke

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Firoz Kumar 5 years, 3 months ago

Mixture define

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Is sponge a solid matter ?

Posted by Mumal Rathore 5 years, 3 months ago

CBSE > Class 09 > Science

3 answers

Janvi Verma 5 years, 3 months ago

Yes,ofcourse

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Raju Singh 5 years, 3 months ago

Yes it is a solid matter

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Sushree Tarini Dash 5 years, 3 months ago

Yes it is

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Which phylum, nervous system develops for the first time

Posted by Shubham Kunar Singh 5 years, 3 months ago

CBSE > Class 09 > Science

1 answers

Shubham Kunar Singh 5 years, 3 months ago

Coelenterates

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How camera works

Posted by Kartik Sharma 5 years, 3 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 5 years, 3 months ago

Working of a pinhole camera

Place a luminous object such as a burning wick (XY) of the candle in front of the pinhole, an inverted picture X’Y’ of the wick is obtained on the wax paper. This picture is called the image.
The image obtained is inverted.
Such an image is formed because the light travels in a straight path. Hence, light from the upper point X of the wick passes through the pinhole and strikes the wax paper at X’.
Similarly, light from the lower point Y of the wick passes through the pinhole and strikes the wax paper (or screen) at Y'.
When light from all other points between X and Y passes through the pinhole they strike the wax paper in between X' and Y'. Hence, an inverted image is formed on the wax paper.

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What is equation og magnism cholide

Posted by Mani Monga 5 years, 3 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 5 years, 3 months ago

MgCl₂ can be extracted from sea water or brine and is chemically named as Magnesium Chloride.
Magnesium Chloride is also called Magnesium dichloride or magnesium (II) chloride or Chloromagnesite and has one magnesium (Mg) and two chloride ions (Cl-).

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Covert 293k into Celsius scale

Posted by Karan Singh 5 years, 3 months ago

CBSE > Class 09 > Science

2 answers

Vaibhav Kumar 5 years, 3 months ago

To convert temperature on kelvin to Celsius The given temperature 273 k Convert = 293 - 273 = 20° C

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Rahul Rohit 5 years, 3 months ago

To convert temperature on the Kelvin scale to the Celsius scale you have to subtract 273 from the given temperature. So here, 293-273=20

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activity 8.9 answer for motion lesson

Posted by Mani Gandan 5 years, 3 months ago

CBSE > Class 09 > Science

1 answers

Ravi Bajaj 5 years, 3 months ago

Hscus

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What are the shapes of human body's cells

Posted by Dhruv Saini 5 years, 3 months ago

CBSE > Class 09 > Science

1 answers

Meghna Thapar 5 years, 3 months ago

The shape and size of cells are related to the specific function they perform. Some cells like Amoeba have changing shapes which helps in its locomotion. The shape of the cell may be variable like white blood cells. Fixed shape of cell occurs in most plants and animals.

The size of different cells ranges between broad limits. Some plant and animal cells are visible to the naked eye however, some are microscopic.

Each living cell has the capacity to perform certain basic functions that are characteristic of all living forms. There is a division of labour in multicellular organisms such as human beings. Different parts of the body perform different functions like the human body has a heart to pump blood and stomach to digest food. Similarly, division of labour is also seen within a single cell. Each cell has got certain specific components within it known as cell organelles which perform a special function such as making new material in the cell, clearing up the waste material from the cell.

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When Leeuwenhoek discovered

Posted by Dhruv Saini 5 years, 3 months ago

CBSE > Class 09 > Science

2 answers

Yogita Ingle 5 years, 3 months ago

Leeuwenhoek discovered protozoa.

In 1674, with the help of improved microscope, A. Leeuwenhoek discovered the free living cells in pond water for the first time.

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Kartik Sikarwar 5 years, 3 months ago

Protozoa

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What is mean by molybdenum

Posted by Jeevitha R 5 years, 3 months ago

CBSE > Class 09 > Science

1 answers

Meghna Thapar 5 years, 2 months ago

Molybdenum is an essential trace mineral. It is found in foods such as milk, cheese, cereal grains, legumes, nuts, leafy vegetables, and organ meats. Molybdenum is most commonly used for molybdenum deficiency. Some electrical filaments are also made from molybdenum. The metal is used to make some missile and aircraft parts and is used in the nuclear power industry. Molybdenum is also used as a catalyst in the refining of petroleum. Molybdenum is primarily used as an alloying agent in steel.

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When we add water in flour why intermolecular force increase

Posted by Vikas Akshat 5 years, 3 months ago

CBSE > Class 09 > Science

1 answers

Vaibhav Kumar 5 years, 3 months ago

When we add water into flour the intermolecular force increase because water is found in the liquid state and we known that liquid has more molecular space and less molecular force thus, it is added in flour the molecular space of water is occupied by the flour and thus it molecular force increase

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What is larent heat

Posted by Sahuri Uttri Tol Kalyanpur 5 years, 3 months ago

CBSE > Class 09 > Science

1 answers

Gaurav Seth 5 years, 3 months ago

Heat required to change the state of a body from one to another without changing its temperature is called as latent heat

Latent heat is of two types:

i)Latent heat of fusion(L_f)
ii)Latent heat of vaporization(L_v)

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Where are proteins synthesised inside the cell?

Posted by Sonali Singh 5 years, 3 months ago

CBSE > Class 09 > Science

2 answers

Aditya Yadav 5 years, 3 months ago

What are the chargcterstics of particles of matter

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Gaurav Seth 5 years, 3 months ago

Proteins are synthesised by ribosomes which are RNA protein complexes. Ribosomes translate the mRNA into proteins.
In prokaryotic cells, proteins are synthesised in the cytosol because membrane bound cell organelles are absent and ribosomes are present in the cytosol.
In eukaryotic cells, proteins are synthesised in the rough endoplasmic reticulum or RER as ribosomes are present on the membrane of RER. Proteins are synthesised by the ribosomes and enter the cisternae of endoplasmic reticulum through channels present in the membrane.

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In which season zaid crops are growing

Posted by Ashok Kumar 5 years, 3 months ago

CBSE > Class 09 > Science

4 answers

Isha Sharma 5 years, 3 months ago

Zaids crops are grown in the Season of April -may during summer

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Abhinandan Gupta 5 years, 3 months ago

Ribosomes

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Sonali Singh 5 years, 3 months ago

Where are proteins synthesised inside the cell

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Yogita Ingle 5 years, 3 months ago

Zaid Cropping season - April- May
Zaid cropping season is during summer season in India.
Zaid crops are Water melons, Bitter gourds, Musk melons, Vegetables etc
The significance of Zaid season is that crops grown on irrigated lands as they are grown before monsoon arrival time.

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what. do you. understand. by the. motion of an object

Posted by Sharla Sharma 5 years, 3 months ago

CBSE > Class 09 > Science

2 answers

Abhinav Patil 5 years, 3 months ago

When the object is move from one location to the other location with repesct to time then it is said to be in motion

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Shaurya Mittal S0009512 5 years, 3 months ago

When an object moves it is defined as motion

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What is plasma therapy

Posted by (つ✧Devesh Kumar✧)つ Dwivedi 5 years, 3 months ago

CBSE > Class 09 > Science

1 answers

Yeshwanth Y 5 years, 3 months ago

For example we take corona is affected for someone and he was out of danger and he is discharged after sometime another fellow got corona and he was in critical stage the doctors call the fellow who was discharged from hospital to take his blood because in his blood already antibodies will be their so the doctors seperate the plasma from the blood and inject into the critical patient this is known as plasma therapy

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Four characteristic of prokaryotic and eukaryotic

Posted by Nishant Paliwal 5 years, 3 months ago

CBSE > Class 09 > Science

1 answers

Neelavati Basingda 5 years, 3 months ago

(a) Prokaryotic- 1. cell without nucleus is called prokaryotic . 2. Except ribosomes all other cell organelles are absent . 3.60s ribosomes are present . 4. Examples - bacteria, bluegreen algae ,cyanobacteria . (b) Eukaryotic- 1. Cell with nucleus is called eukaryotic cell . 2. Ribosomes and all other cell organelles are present . 3.80s ribosomes are present . 4.Examples - all higher plants and animals.

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Technique like hybridization and introducing a gene in a plant results ____________ crop

Posted by Shaurya Mittal S0009512 5 years, 3 months ago

CBSE > Class 09 > Science

3 answers

Abhinandan Gupta 5 years, 3 months ago

Hybrid variety of crop

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Satyam Chaubey 5 years, 3 months ago

Hybrid

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Abhinav Patil 5 years, 3 months ago

HYBRID

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Which organelle is responsible for making_ a. Maintain water and solute transport, protein, lipids, modification of protiens, breaking the substance, cell division and replication, making food, storing large amount of anything, giving cell its shape, energy production

Posted by Diya Jadon 5 years, 3 months ago

CBSE > Class 09 > Science

1 answers

Abhinav Patil 5 years, 3 months ago

Cell orgnellas

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What is multicellular

Posted by Vishal Singh 5 years, 3 months ago

CBSE > Class 09 > Science

4 answers

Satyam Chaubey 5 years, 3 months ago

Organisms made of more then one cell is known as multicellular

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Shaurya Mittal S0009512 5 years, 3 months ago

Organisms made of more than one cell eg hens egg

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Yogita Ingle 5 years, 3 months ago

Multicellular organisms

Multicellular organisms are composed of many cells.
The labour of performing different functions is divided between the various cells in these organisms.
Some multicellular organisms have different cells. For example, Human beings have different cells of different shapes and sizes in their body to perform different functions.

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Music Lover? 5 years, 3 months ago

Which organism have more than one cell

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The cell of cork are dead and have a chemical in their wall that make them imprvious to gases and war the chemical is

Posted by Bhumika Patel 5 years, 3 months ago

CBSE > Class 09 > Science

1 answers

Abhinav Patil 5 years, 3 months ago

Cutin

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Rita jogs on a circular track of radius 50m and takes 6min to complete one round. She jogs for 33min. Find her distance and displacement.

Posted by Tejaswini K 5 years, 3 months ago

CBSE > Class 09 > Science

1 answers

Vaibhav Kumar 5 years, 3 months ago

Given, Radius of the circular track = 50m The time taken by her to complete 1 round =6min We have to find, Distance = ? Displacement = ? We have to find the total path length Thus, we have to found the circumference of the circular path By using formula = 2 pie r C = 2 pie r = 2 × 3.14 × 50m ( pie = 22/7 or 3.14 ) = 314m The total circumference of the circular path = 314m According to the Question, By using the unitary method, If the distance travelled by her in 6min = 314m Then, " " " " " " 1min = 314m/6min Therefore, the total distance travelled by her in 33min. = 314m/6min × 33min = 1727m or 1,727m Distance = 1,727m or 1.727km Displacement = 0m. ( in circular path the displacement is always Zero, because the Initial point and final Point concluded. )

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What is valency of an element

Posted by Gurleen Kaur 5 years, 3 months ago

CBSE > Class 09 > Science

2 answers

Vaibhav Kumar 5 years, 3 months ago

Valency of an element is the combining capcity of an element ( or radicals) For an example Sodium ( NA ) valency = 1 Its a positive radical Chloride ( CL ) valency = 1 Its a negative radical Thus, we known that to form a Chemical formula or Chemical Equation we have to combine the +ve radical and the -ve radical Now, we simply to known and understand this Sodium. Chloride NA. By. CL Cross Multplica- tion 1. 1 = NACL

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Gaurav Seth 5 years, 3 months ago

Valency means combining capicity of an element .

Relationship between the number of valence electrons and valency:

Valence electrons are the number of electrons present in the outermost shell of an atom.

Valency is the combing capicity of an element to form bonds with the other elements.

For Example:

Let us take the case of Oxygen whose Atomic number is 8.Thus,its electronic configuration is 2,6.

Oxygen has 6 electrons in its outermost shell and requires 2 more electrons to complete its octet state.

So,here Oxygen has 6 valence electrons and 2 as its valency .

The number of valence electrons increases from left to right in the periodic table.

If the number of valence electrons of an element is equal to 4 as that of carbon,the the element would also have same valency that is 4.