Explore topic-wise InterviewSolutions in Current Affairs.

(d) 6% per annum

Correct answer is (b) serai stages

Correct answer is (c) Stratification

Correct answer is (a) First serai stage

Correct option is: (c) decomposers

(b) Mitakshara Law

आयन-आयन विकर्षण के कारण |

एसेटिक अम्ल के 3 – 5% विलयन से सिरका बनता है ?

(d) 15 million km

Since partnership is the outcome of an agreement, the minimum number of persons required to form a partnership is two. Maximum is restricted to 10 in the case of banking business and to 20 in all other cases.

कोलाइडल  के रूप में |

Correct answer is (c) 2-10%

According to S. Evelyn Thomas “the retailer is the last of the many links in the economic chain whereby the consumer’s wants are satisfied smoothly and efficiently by retailers”.

Correct answer is (d) Newly-exposed habitat with no record of earlier vegetation

The individual transitional communities formed during succession are termed serai communities.

Correct answer is (b) Stratification

(c) Fragmentation → Leaching → Catabolism → Humification → Mineralization

Correct answer is

Correct answer is (b) Stratification

(1) All food chains and webs have at least two dr three trophic levels. Generally, there are a maximum of four tropic levels. Many consumers feed at more than one tropic level. 

(2) Man is a primary consumer when he eat plants such as vegetables. Vegans and vegetarians who do not consume any animal product, fish or meat of any kind are primary consumers. They belong to the second trophic level. 

(3) But some humans have different dietary choices. Many humans are omnivores, meaning they consume both plant and animal material. Thus, they may be on the third or even fourth tropic level. 

(4) For example, if man consumes goat meat he is a part of the third tropic level. 

(5) But when he eats bigger fish (and considering fish eats smellier fish) he becomes tertiary consumer on the fourth tropic level.

According to Cundiff and Still “wholesaler buys from the producer and sells merchandise to the retailers and other merchants and not to the consumers.

Merchant middleman can be further sub – divided into: 

1. Wholesaler 

2. Retailer

Interaction of biotic and abiotic components, results in a physical structure of ecosystems.

Stratification seen in forested land is as follows trees occupying top vertical strata or layer of a forest, shrubs the second strata and herbs and grasses occupying the bottom layer.

Correct option is: (c) Elton

1. Secondary succession begins in areas where previously natural biotic communities were present. But later were destroyed due to causes such as abandoned farm lands, burnt or cut forests, flooded lands, etc. 

2. Secondary succession is faster than primary succession because already there is some soil or sediment present. 

3. It occurs in the form of changed vegetation. But due to changed vegetation, there is also change in the resident animals that depend for food and shelter. 

4. Thus, with secondary succession, the numbers and types of animals and decomposers also change. 

5. During succession, natural or human induced disturbances (fire, deforestation, etc.), can convert a particular serai stage of succession to an earlier previous / preceding stage. 

6. Sometimes, disturbances like this can create new conditions that encourage some species and eliminate other species.

The cyclic movement of nutrient elements through the various components of an ecosystem, is called nutrient cycling.

1. Succession of plants is of two types based on the nature of the habitat. These are hydrarch or hydrosere which is based on water or very wetland areas and xerarch or xerosere based on very dry areas. 

2. In wetter areas hydrarch succession begins and then successional series progress from hydric to the mesic conditions. 

3. Xerarch succession starts in dry areas and the series progress from xeric to mesic conditions. 

4. Both hydrarch and xerarch successions lead to mesic or medium water condition which is neither too xeric nor too hydric.

1. Nudation 

2. Invasion 

3. Ecesis 

4. Aggregation

5. Competition and co-action 

6. Reaction and stabilization

Earth’s crust.

1. Gaseous and 

2. Sedimentary.

Correct answer is (a) Released in atmosphere through transpiration.

Correct answer is

The pattern of energy exchange in an ecosystem is called a ‘Pyramid of energy’.

(i) Nitrogen cycle is called bio-geochemical cycle as it undergoes biological as well as geochemical processes.

(ii) Nitrogen cycle is important to us as nitrogen availability can affect the rate of key ecosystem processes, including primary production and decomposition.

(iii) Important processes in the nitrogen cycle include fixation, ammonification, nitrification, and denitrification.

(iv) Human modification of the global nitrogen cycle can negatively affect the natural environment system and also human health.

(v) Human activities such as fossil fuel combustion, use of artificial nitrogen fertilizers, and release of nitrogen in wastewater have dramatically altered the global nitrogen cycle.

• The cyclic flow of nutrients within an ecosystem is called bio-geo-chemical cycles. 
• Nutrients, necessary for the growth of organisms are continuously transferred from abiotic to biotic factors and biotic to abiotic factors within an ecosystem. 
• Any imbalance in the cycles will break the link between the biotic and abiotic factors. 
• Therefore, equilibrium is necessary between bio-geo-chemical cycles.

Functions of an ecosystem:

1. Biological energy flow. 

2. Productivity of the ecosystem. 

3. Photosynthesis and respiration that take place in the ecosystem. 

4. Nutrient cycles operating in the ecosystem. 

5. Regulation of the environment by the organisms and the regulation of the organisms by the environment in turn. 

6. Interactions of biotic and abiotic components of the ecosystem.

Ecosystems are of two types, viz. natural ecosystem and artificial ecosystem. 

(1) Natural ecosystems : The ecosystems which operate under natural conditions without any much major interference by man are called natural ecosystems. E.g. terrestrial ecosystems such as grasslands, forests, deserts, etc. or aquatic ecosystems such as lakes, river, wetland, etc.

(2) Artificial ecosystems : The man engineered ecosystems which are maintained artificially by man by the addition of energy are called artificial ecosystems. These ecosystems are dependent upon manipulations from human beings. 

E.g. croplands, aquarium, aquaculture, etc. are the types of artificial ecosystems.

1. All animals depend on plants for food either directly as in case of herbivorous animals or indirectly as in case of carnivorous animals. 

2. Animals cannot perform photosynthesis as they are not autotrophic. 

3. They are heterotrophic and hence all are called consumers.

Lysine and Arginine.

In prokaryotes, the DNA is organised in large loops held by positively charged proteins in a region called nucleoid.

Nucleoid is the region in prokaryotic cells where DNA is held with prositivelycharged proteins.

Correct option is (d) Safety needs

Correct option is (b) Experimentation.

Correct option is (a) wants are a socialized manifestation of underlying needs.

X—Meiosis (Reduction division); A—Mitosis; B—Mitosis; C—Mitosis; D—Cells reorganised as polar nuclei, antipodals and egg apparatus.

Conservation of momentum is the physical principle that is involved in the working of a jet aeroplane.