Explore topic-wise InterviewSolutions in Current Affairs.

Inter-tidal, Littoral, Sub-littoral zones.

1. Stratification 

2. Zonation.

Correct answer is (c) Burning of fossil fuels

Correct answer is (c) weathering

(1) For considering the energy flow in an ecosystem the following aspects have to be taken into account:

• The efficiency of the producers in the absorption and conversion of the solar energy. 
• The quantity of converted energy is used by the consumers. 
• The total input of energy in the form of food and its efficiency of assimilation by the consumers. 
• The amount of energy is lost through respiration, heat, excretion, etc. 
• The ultimate gross net production.

(2) The energy captured by autotrophs never returns back to the sun. The energy obtained by the herbivores will never go back to autotrophs. Hence energy flow is always unidirectional.

(3) The energy flow through different trophic levels is progressive and hence previous trophic level cannot get this back. 

(4) The amount of energy keeps on decreasing as it travels to further trophic level. This loss of energy is due to dissipation as heat formed during various metabolic activities of the organism. The energy loss is measured as respiration coupled with unutilized energy. 

(5) If the food chain is shorter there is greater amount of available food energy. When the length of food chain increases, there is corresponding more loss of energy.

By identification and enumeration of plant and animal species of a given ecosystem, its species composition can be decided.

Correct answer is (b) Proteins

Correct answer is (c) Ocean

Correct answer is (d) Hairs

1. Subtidal channels : These are important habitat for fish during low tide. This region allows good drainage and flooding in mudflats. 

2. Mudflats : This area is very rich in invertebrate life. Therefore, many wading birds are dependent for food in this area. Algal mat is also observed on mud flats. 

3. Low marsh : This area is a good habitat for cordgrass, insects, herons and egrets and the clapper rails. 

4. High marsh : This region supports pickleweed and patches of cordgrass. Sparrow and clapper rails are seen here.

1. There are two spatial patterns recognized in an ecosystem, viz. zonation and stratification. 

2. Zonation is the spatial pattern which occurs horizontally along the ground. Along a horizontal gradient, the density and distribution of the species keep on varying.

3. Stratification is the spatial pattern which occurs vertically. This is determined by the height of organisms. Such stratification is seen in forest community where trees of different species grow to different heights.

(1) There are two main components of the ecosystem, viz. abiotic components and biotic components.

(2) Abiotic components include all the inorganic substances such as B S, C, N, H, etc., their distribution and amount available in an ecosystem and the organic compounds such as proteins, carbohydrates, lipids, etc. along with the climate of that region.

(3) Biotic components include all the living organisms living in an ecosystem. The living organisms may be autotrophic or producers and converters or transducers. These are either green plants having photosynthetic abilities or chemosynthetic microorganisms. The heterotrophic organisms are called consumers.

They can either be macroconsumers or microconsumers.

1. Macroconsumers are herbivores, carnivores or omnivores as per the order in which they appear in the food chain. 

2. Herbivores are primary consumers while the carnivores are secondary consumers. 

3. Omnivores can be secondary or tertiary consumers. 

4. Microconsumers are decomposing organisms and hence they are also called decomposers. They have saprophytic mode of nutrition. Bacteria, actinomycetes and fungi are some of the microconsumers.

5. Microconsumers decompose complex organic compounds from dead and living protoplasm and release the inorganic nutrients obtained from them, back to the environment.

• Plants of the ecosystem store some of the solar energy in the form of food. 
• Before reaching the decomposers, this energy is passed on from one trophic level to the next. 
• At every trophic level, some amount of energy is used by the organism for its own life processes and some amount of energy is lost to the surroundings. 
• Decomposers dissipate some amount of energy in the form of heat. 
• However, no part of the energy ever returns to the Sun. Hence, such passage of energy is referred to as ‘one way’ transport. 
• Therefore, energy is maximum at the base of the pyramid and is least at the apex, e.g. 
• Phytoplankton which form the base of the pyramid have 10,000 kcal of energy while humans at the apex have 10 kcal of energy.

Reservoir for gaseous cycles is Atmosphere.

1. For every ecosystem there are four important functional aspects viz. productivity, decomposition, nutrient cycling and energy flow. 

2. In a small pond ecosystem, too, there are complex interactions. 

3. Pond is a shallow water body in which all the above four basic processes of an ecosystem are observed. 

4. The abiotic component is water along with dissolved inorganic and organic substances and rich soil deposit at the bottom of the pond. 

5. The sunlight acts as a source of solar energy, the cycle of temperature, day-length and other climatic conditions regulate the rate of function of the entire pond. 

6. Phytoplankton are the main producers along with algae and other aquatic plants. 

7. Zooplankton, aquatic insects and fish are the consumers. 

8. The decomposers are the fungi and bacteria present in the bottom soil.

1. Pioneer species are the ones that invade a bare area during primary succession. 

2. Crustose lichens which are able to secrete acids to dissolve rock usually start as pioneer species. They bring about weathering of rocks and soil formation. 

3. Later here bryophytes, mosses are settled as they can take hold in the small amount of soil. They are then followed by herbaceous plants, and after several more stages, ultimately a stable climax forest community is formed.

• The different types of bio-geo-chemical cycles are nitrogen, oxygen, carbon, water vapour, iron, calcium, phosphorus, etc. 
• Nutrients, necessary for the growth of the organisms are continuously transferred from abiotic to biotic factors and biotic to abiotic factors within an ecosystem. 
• These cycles operate continuously through the medium of the biosphere formed by the lithosphere, atmosphere and hydrosphere.
• The recycling of biological, geological and chemical sources of nutrients takes place through these cycles.
• Nutrients from the biosphere enter the bodies of plants and animals. Eventually, after death, all types of consumers are decomposed by decomposers like bacteria and fungi and they are again released into the biosphere and are used again by living organisms.
• Therefore, these cycles help in maintaining the flow of nutrients and energy through ecosystem and maintaining the equilibrium in the ecosystem.

• Bio-geo-chemical cycles always involve the achievement of equilibrium, i.e., a balance in the cycling of the nutrients between the spheres. 
• Human activities that are known to be environmentally unfriendly can disrupt this balance. 
• We should avoid deforestation as trees play an important role in maintaining the balance. 
• We should avoid overuse of fertilizers. The fertilizers get washed away in the nearby water bodies disrupting the balance. 
• Avoid burning of fossil fuels as these fuels release a large amount of carbon in the form of carbon dioxide, thus disrupting the balance. 
• Vehicular emissions is another contributor to the disruption in balance of the various cycles.
• These emissions release oxides of nitrogen and carbon and other hazardous air pollutants. 
• So, we must use better quality fuel like CNG or ethanol to reduce vehicular emissions.

• Each level in the food chain is called a trophic level. 
• The amount of matter and energy gradually decreases from producers at the lowest level to the top consumers at the highest level.
• The initial quantity of energy goes on decreasing at every level of energy exchange. 
• Similarly, the number of organisms also decreases from the lowest level to the highest level. 
• This pattern of energy exchange in an ecosystem is called a Pyramid of energy.

(1) False. The amount of matter and energy goes on decreasing at every level in a food chain. 

(2) False. Charles Elton first proposed the concept of Ecological Pyramid. 

(3) True 

(4) True 

(5) True 

(6) False. Carbon dioxide is released in the atmosphere through respiration, burning of fossil fuels and wood, forest fires and volcanic activity.

• Each level in the food chain is called a trophic level.
• A trophic level is the step at which the organism obtains its food in the chain. 
• The amount of matter and energy gradually decreases from producers at the lowest level to the top consumers at the highest level.

Correct answer is (d) They face adverse conditions and get established there.

1. Trophic level.

2. Decomposers.

3. Photosynthesis.

4. Ammonification.

5. Nitrogen fixation.

1. Primary succession means the initial development of life on barren piece of land. 

2. Primary succession occurs on newly cooled lava, rocks and newly created pond or reservoir. In a newly formed volcanic island, the life starts and takes up millions of years to develop the whole biomass. 

3. In the successive serai stages, there is a change in the diversity of species of organisms, increase in the number of species and organisms as well as an increase in the total biomass. 

4. The establishment of a new biotic community is generally very slow and takes millions of years. 

5. Primary succession depends on climatic condition, soil characteristics and natural processes.

1. In aquatic habitats the pioneer species in primary succession are the small phytoplankton. 

2. Phytoplankton are replaced by rooted- submerged plants (e.g. Hydrilla), rooted- floating angiosperms (e.g. Lotus) followed by free-floating plants (e.g.Pistia), then reed swamp (e.g. Typha), marshmeadow (e.g. Cyperus), scrub (e.g. Alnus) and finally the trees (e.g. Quercus) in a very systematic and gradual way. 

3. The climax again would be a forest. With passage of time, the water body is converted into land.

• Interaction go on continuously between producers, consumers and decomposers. 
• There is a definite sequence in these interactions which is called the food chain. 
• Each chain consists of four, five or more links. 
• An ecosystem consists of many food chains that are interconnected at various levels. 
• Thus, a food web is formed. An organism may be the prey for many other organisms.
• For example, an insect feeds upon leaves of various plants but the same insect is the prey for different animals like frog, wall lizard, birds, etc. 
• Thus, many food chains interconnected together form an intricate web called as food web.

• An ecosystem consists of many food chains that are interconnected at various levels. This is called food web. 
• An organism may be the prey for many other organisms. 
• For example, an insect feeds upon leaves of various plants but the same insect is the prey for different animals like wall lizards, birds etc. 
• This forms an intricate web instead of a linear food chain. Such an intricate network is called as food web.
• Generally food webs are formed everywhere in nature.

Merchant middlemen can be classified into Two categories.

The function of the reservoir is to meet with the deficit, which occurs due to imbalance in the rate of influx and efflux in any ecosystem.

Small phytoplankton are the pioneers in the aquatic habitat during primary succession.

1. Public Provident Fund (PPF): It is the safest long – term investment option for the investors in India. It is totally tax – free. PPF account can be opened in bank or post office. The money deposited cannot be withdrawn before 15 years and an investor can earn compound interest from this account.

However the investor can extend the time frame for the next five years if the investor does not opt to withdraw the amount matured for payment at maturity date. PPF investor can take loan against PPF account when he/she experiences financial difficulties.

2. Mutual Funds: An individual investor who wants to invest in equities and bond with a balance of risk and return generally can invest in mutual funds. Nowadays people invest in stock markets through a mutual fund. Systematic investment plan is one of the best investment options in India.

3. Direct Equity or Share Purchase: An individual can opt for investment in shares. But he has to analyse the market price of various shares traded in stock exchange, reputation of the company, consistency in the payment of dividend, the nature of the project undertaken by the company, growth prospects of industry in which a company is operating, before investing in shares. If the investment is made for a long time, it may yield good return.

4. Real Estate Investment: Real estate is one of the fastest growing sectors in India. Buying, a flat or plot is supposed to be the best decision amongst the investment options. The value of the real asset may increase substantially depending upon the area of location and other support facilities available therein.

The interconnection among different food chains in an ecosystem at various levels is called as a food web.

Broker are agents who merely bring the buyer and the seller into contact.

Correct Answer is: (b) Factor

The term ‘Middlemen’ refers to all those who are in the link between the primary producer and the ultimate consumer in the exchange of goods or service.

A factor is a mercantile agent to whom goods are entrusted for sale by a principal. He takes physical possession of the goods, though he does not obtain ownership of the goods. A factor sells goods in his own name without revealing the name of his principal.

Trade middleman who acts as a link between wholesaler and customers refers to a Retailer.

Distribution of temperature on the surface of the earth is not the same, but it varies. This variation in temperature is called ‘arbitrariness’ in context to different places.

(a) Wholesaler

A channel is the route through which the goods are passed on to the ultimate consumer. There are direct channels or routes of distribution without middlemen. Indirect channel consists of one or more middlemen performing different functions. Middlemen help in the flow of goods towards the lakhs or crores of consumers.

(b) Wholesaler

In the areas where the clouds are present and where there is rain, the temperature is not high, because the clouds reflect the rays of the sun while there is more heat in the cloud – free areas;

Temperature depends on the insolation, so the atmospheric heat is expressed as temperature.

The radiation that is emitted from the surface of the Sun is called solar radiation.

Following are the characteristics of retail traders:

1. Retailer generally involves dealing in a variety of items. A retailer makes purchases from producers or wholesalers in bulk for sale to the end consumers in small quantities.

2. Retail trade is normally carried on in or near the main market area.

3. Generally, retailers involve buying on credit from wholesalers and selling for cash to consumers. 

4. A retailer has indirect relation with the manufacturer (through wholesalers) but a direct link with the consumers.