Friday, October 28, 2016




Commonly Asked Questions

Q1: What was Federic Sorrieu's dream of 'Democratic Republics'?

Answer: In 1848, Federic Sorrieu prepared a print called 'The Dream of Worldwide Democratic and Social Republic. He tried to visualise his dream of a world made up 'democratic republics'. According to him:

1. People of Europe and America marching and forming a long train towards the statue of liberty and offering homage to it.

2. He personified liberty as a female figure.

3. In his glorified dream, he grouped people of the world as distinct nations which are identified by their national costumes and national flags.

4. From heavens, Saints and angels gaze upon the scene symbolising the fraternity among the nations of the world.

Q2: How the concept of nation was visualised in Europe in 18th and 19th century?

1. Artists in 18th and 19th centuries tried to give a face and personify the concept of a nation.
2. Nations were portrayed as female figures and alma mater (motherlands).
3. The Female figure became an allegory of the nation. e.g. Germania. In her visual representation, Germania wears a crown of oak leaves as the German Oak stands for heroism.

Thursday, October 27, 2016

CBSE Class 9, 10, 11, 12 - Mathematics - Know about Special Constants

Know about Special Constants

CBSE Class 9, 10, 11, 12 - Mathematics -  Know about Special Constants

Change is the only constant in our lives. However, there are constants or constant numbers that are frequently used in the domains of Science, Mathematics, Economics etc.

Do you know what is golden ratio?

What is the value of Pi?

What are transcendental numbers?

What's the value of cube root of 2?

Tuesday, October 25, 2016

CBSE Class 6, 7 - English Grammar Worksheet -2 (2016)


Worksheet for Standrard V, VI and VII students.

Tough Level: Easy
CBSE Class 6, 7 - English Grammar Worksheet -2 (2016)

Write the correct option which you find the most appropriate. 

1.  The plural of dynamo is 

(a) dynamos
(b) dynamoes
(c) dynamose
(d) dynamoss

2. ‘The carpets have been cleaned’. The singular of this sentence is 

(a) The carpets have been cleaned
(b) The carpetse have been cleaned
(c) The carpett has been cleaned
(d) The carpet has been cleaned

3. ‘He walked himself homewards, whistling like a lark’.
     'Like a lark' here is a 

(a) simlie
(b) metaphor

4: Identify the correct sentence from the following:

(a) The team play.
(b) The class make too much noise
(c) The machinery was damaged while transporting.
(d) The milk are in the refrigerator.

Sunday, October 23, 2016

CBSE Class 11 - Biology - Chapter 2 - Biological Classification (Q and A)

CBSE Class 11 


Chapter 2 - Biological Classification

NCERT Chapter Solutions

CBSE Class 11 - Biology - Chapter 2 - Biological Classification (Q and A)

Q1: Discuss how classification systems have undergone several changes over a period of time?

Answer: The classification systems have undergone several changes with time.

The first attempt of classification was made by Aristotle. He classified plants as herbs, shrubs, and trees. Animals were classified on the basis of presence or absence of red blood cells. This system of classification failed to classify all the known organisms.

Linnaeus gave a two kingdom system of classification i.e. kingdom Plantae and kingdom Animalia. However, this system did not differentiate between unicellular and multicellular organisms and between eukaryotes and prokaryotes. Thus a large number of organisms could not be classified merely under the two kingdoms.

Later a five kingdom system of classification was proposed by R.H Whittaker in 1969. On the basis of characteristics, such as cell structure, mode of nutrition, presence of cell wall, etc., five kingdoms, Monera, Protista, Fungi, Plantae, and Animalia were formed.

Later Monera was divided further into Archaebacteria and  Eubacteria because Archaebacteria were different from bacteria in terms of different type of cell wall structure.

Q2: Who is known as Father of Taxonomy? Name the book he published on taxonomy. What's his the greatest contribution in naming species.

Answer: Linnaeus. In 1758 he published his famous book systema naturae. His greatest contribution to taxonomy was the use of binomial nomenclature for all species of animals and plants

Q3: State two economically important uses of:

(a) Heterotrophic bacteria
(b) Archaebacteria

(a) Uses of Heterotrophic bacteria

  • Commercial and Domestic Use: They (Lacto bacillus) help in the production of curd from milk.
  • Decomposers that help in the formation of humus.
  • Medicinal use: Many antibiotics are obtained from some species of bacteria.
  • Nitrogen Cycle: Many soil bacteria help in fixation of atmospheric nitrogen.

(b) Uses of Archaebacteria
  • Live in guts of  ruminant animals such as cows and buffaloes and they produce methane anaerobically (biogas) from the dung of these animals.
  • Methanogens are also involved in the formation of biogas and sewage treatment.

Q4: What is the nature of cell-walls in diatoms?

Answer: The cell wall of diatom is made of silica. It consists of two thin overlapping shells that fit into each other such as a soap box with lids. When the diatoms die, the silica in their cell walls gets deposited in the form of diatomaceous earth. This diatomaceous earth, being gritty, is used in polishing, filtration of oils and syrups.

Q5: Name the algae which is a source of iodine.

Answer: Brown algae called kelps, specially from species of Laminaria.

Saturday, October 22, 2016

CBSE Likely To Reintroduce CBSE Class X Board Exams From 2018

CBSE Likely To Reintroduce CBSE Class X Board Exams From 2018

CBSE Likely To Reintroduce CBSE Class X Board Exams From 2018

Most likely the meeting on October 25, 2016 would take a final call whether to reintroduce Class 10 Board Examination from 2018 on wards. The meeting will be conducted by Central Advisory Board of Education (CABE) and it will be chaired by Union HRD Minister Prakash Javadekar.

To reduce pressure on students CBSE decided to scrap Class 10 board examination six years ago. According to HRD, the feed back received about the falling academic standards and students unable to take pressure directly appearing in Class XII board examination, the ministry is reviewing the decision.


CBSE Class – XI - Biology - NCERT Chapter 1 - The Living World (NCERT Chapter Solutions)

The Living World

Class – XI - Biology - NCERT Chapter 1 Solutions

CBSE Class – XI - Biology - NCERT Chapter 1 - The Living World (NCERT Chapter Solutions)

Question 1: Why are living organisms classified?


Classification helps us understand biodiversity better way. Biodiversity have direct and indirect economic benefits to humans as well as to our ecosystem. Systematic study of such biodiversity is essential to better understand the inter-relationships in our ecosystems. Following are the needs to classify them:

Plants and animals have valuable genetic variation information. It will help us understand the ways evolution take place.

Humans often benefits from plants and animals in different ways. Systematic study will help exploring other potential benefits.

Certain species warn us of imbalances in our ecosystem. e.g. white-rumped vultures became almost extinct because of use of drug brufen (diclofenac) in domestic animals. When vultures ate these dead animals, it led to their kidney failures. Systematic study of the organisms would help in restoring the balance in their ecosystems.

Plants and animals have been the inspiration for technology and engineering design. e.g. SONARS and RADARS work on the same acoustics principles as used by bats. Classification will help us revealing such more inspirations.

It is estimated that the Earth has almost 8.8 million animal, plant, and fungi species, but we’ve only discovered less than a one fourth of this. A large variety of plants, animals, and microbes are found on earth. All these living organisms differ in size, shape, colour, habitat, and many other characteristics. Classification gives a system for identification of known and unknown organisms.

Question 2: Why are the classification systems changing every now and then?

Answer: In the last few hundred million years, plants and animals have undertaken an epic evolutionary journey that has altered the very make-up of the planet. Millions of plants, animals, and microorganisms are found on earth. Many of these have been identified by the scientists. While many new species are still being discovered around the world.

Another reason is that scientists started classifying organisms on the basis of evolutionary relationships rather than solely on the basis of similarities in physical traits.

Therefore, to classify these newly discovered species and finding new basis of classification, new systems of classification have to be devised every now and then. This creates the requirement to change the existing systems of classification.

Question 3: What different criteria would you choose to classify people that you meet often?

Answer: To classify people we often meet, we try to categorise in an ordered fashion.

To begin with we classify them based on gender. It results in the formation of two major groups- boys and girls.

Each of these two groups can be further classified on the basis of the blood relatives, distant relatives, friends, knowns and strangers.

Finally each individual be identified by its name (first name and sir name)

Question 4: What do we learn from identification of individuals and populations?

① It helps in studying characteristics of an individual or its entire population.
② It helps in identifying similarities and dissimilarities among the individuals of same kind or between different types of organisms.
③ It helps the scientists find basis to classify organisms in various categories.
④ It helps us finding the relation between the individuals (or its population) with the ecosystem (Biotic and Abiotic factors).

Friday, October 21, 2016

CBSE Class 6/7/8/9/10 - शब्द – निर्माण : उपसर्ग

शब्द – निर्माण : उपसर्ग

CBSE Class 6/7/8/9/10 - शब्द – निर्माण : उपसर्ग

प्रश्न:1  उपसर्ग किसे कहते है?

उतर: जो शब्दांश मूल शब्द के प्रारम्भ से जुड़कर उनके अर्थ में विशेषता या परिवर्तन कर देते है, उन्हें ‘उपसर्ग’ कहा जाता हैं|

प्रश्न: 2 हिंदी में कितने प्रकार के उपसर्ग होते है? और इनके उदहारण दीजिए|

उतर: हिंदी में चार प्रकार के उपसर्ग होते है:

(क) संस्कृत के उपसर्ग

(ख) उपसर्ग की तरह प्रयोग किये जाने वाले संस्कृत के अव्यय|

(ग) हिंदी के उपसर्ग

(घ) उर्दू के उपसर्ग

(क) संस्कृत के उपसर्ग:

उपसर्ग                अर्थ                               उदाहरण
अ नहीं, अभाव                          अनाथ, अज्ञान, अधर्म
अनुपीछे, समानअनुकरण, अनुरूप
तक, पूर्णआचरण, आदान, आगमन,आजन्म
उपसमीप,छोटाउपवन, उपकार, उपमंत्री,उपदेश
दुर् कठिन, बुरादुर्बल, दुर्गण, दुरात्मा, दुर्भाग्य
निनीचे, अच्छी तरहनिबंध, निवेदन
निर्रहित, निषेधनिर्गुण, निर्मल
पराउल्टापराजय, पराक्राम
प्रतिप्रत्येक, विरोधप्रतिदिन, प्रतिमास, प्रतिशत, प्रतिकूल
विविशेषता, अलगविरोध विज्ञान, विशेष, विहीन, विहार, विनय
साथसफल, सपरिवार
सुशुभ, अच्छासुंदर सुमति, सुशांत, सुपुत्री, सुगम