May 2023 - quiz sansar

23, May, 2023 0 Comments

What are the aquatic adaptations of mammals?

A few mammals that once lived on land have returned to the sea to continue their evolution. Some animals sought food, others fled from land enemies and some with their enormous bulk of weight were unable for swift land movement preferred swimming and modified their limbs into paddles and other aquatic adaptations during millions of years of evolution.

Of the warm-blooded animals that have returned to sea whales have successfully completed the evolutionary transition. Both sub orders of the Odontoceti that feed primarily upon fishes and Mystacoceti or Whalebone. Whales that feed by means of a peculiar brush like device of Whalebone, which strain out and shallow counter myriads of microscopic ocean animals and maintain a nutritious sea soup supply of unlimited quality. Together with Delphinus (the dolphin), Phocaena, Grampus, Orca (the killer), Monodon (waves) with a single senormous twisted tooth, Physeter (sperm whale) with teeth only in the lower jaw and Hyperodon (bootle nosed whale). Constitute the order cetacea, of infraclass Eutheria, in class-mammalia.

There are nine genera of fossil cetaceans and 27 genera of living ones, some of which are becoming scarce due to relentlessly man hunting. The animals of the order Cetaceans are to be found the largest animals that over lived. The animals are so well adapted to the realm of the sea that they had no need, as some other warm-blooded marine animals do, to go on land to bear, its young. They are remarkably stream-lined. They needs bones have become stabilizing fins and hind legs have completely disappeared. The only remains of external ear are openings on either side of the head just large enough to pass a pencil through. The nostrils have moved from the front to the very top of the head and have become either one or two blow holes which enable the whale to breath without raising itself more than a few inches above the surface of water. A thick layer of blubber conserves the body heat acts as thick blanket of heat retaining blubber under the skin enabling these gigantic animals to pursue their activities even in Arctic waters. It also improves streamlining and acts as a food reserve when the whale travels to warmer waters where its kind of food is not abundant. The largest ever caught female blue whale measured 113.5 feet long, weighted about 170 tons. Because the whale, fixed by the sea from force of gravity, its enormous size increases efficiency. Enormous size ultimately results in vastly greater volume enabling much space for muscles to generate swimming power required to over come the frictional force of water.

The female blue whale gives birth to a single calf every alternate year, their new born is the largest among all the terrestrial mammals example:- having 23 feet length at birth. For seven months the female blue whale supplies its baby with one ton of very rich milk per day. Studying wax plugs laid down in year by year layers inside whale’s ear membranes. The life of blue whale is estanited to 50 years.

Types of ecosystem of the world

In broad sense there are two major types of ecosystem namely terrestrial and aquatic. The terrestrial ecosystem is further divided into the following types of ecosystem-

Forest Ecosystem
Grassland Ecosystem
Desert Ecosystem.

Aquatic ecosystem is divided into two types of ecosystem-

Fresh water ecosystem
Marine or oceanic ecosystem.

The fresh water ecosystem is further divided into pond ecosystem, lake ecosystem, river ecosystem, and spring ecosystem.

Structure of Forest Ecosystem

There are two main components an found in this ecosystems.

(A) Abiotic Components – Forest ecosystem have the following abiotic components – soil, water, light etc.
(B) Biotic components – Forest ecosystem consists of the following biotic components.

1. Producers – All the green plants of a forest ecosystem is producers. They are the main sources of food for forest animals. The plants of a top substratum are angiosperm our and gymnospermous plants. They utilize radiant energy in the greatest extent. Below the level of tress there is a layer of srube and below of its the grasses, hobs, lichens and mosses are found. These plants get least light.

2. Consumers – There are a number of consumers in an old dense forest. Consumers of the first order in the forest are grasshoppers, rabbit, deer, monkey, bird and many other wild herbivores, which utilize plants directly as their food. Secondary consumers are walves, phythons, jackal, etc. which consumes the flesh of herbivores, and lion, tiger, hawks are the consumers of the top level.

3. Decomposers and Transformers – They are microorganisms, chiefly bacteria and fungi, which attack dead bodies of producers and consumers and convert couples organic material into simpler materials. These free simpler materials again return to the abiotic components and are reutilized by producers in their nutrition.

Function of Forest Ecosystem

The components of an ecosystem are connected in a complex web. Function of forest ecosystem includes following cycles –

1. Energy Cycle: The sun starts the food pyramid by feeling the photosynthesis process. Trees and green plants begin all life processes with photosynthesis and the resulting production of plant biomass.

The sun’s energy constantly changes form as plants covert light into plant biomass, which is then consumed by other organisms. Plants perform an important action of energy fixation, which is the basis for all life.

2. Water Cycle: The water cycle collects, purifies, and distributes the world’s water. Without the water cycle, life on earth would be impossible. Trees and plants are part of this water cycle. Transpiration is the controlled evaporation process by which plants lose H2O through the pores in their leaf structures. A full grown tree can transpire hundreds of gallons of water a day during growing season.

3. Nutrient Cycle: Trees rely on nutrients like phosphorous and nitrogen for healthy growth and reproduction. Throughout a tree’s life stages, they constantly use and return nutrients to the soil. Nutrient cycles regularly transform nutrients from the non-living environment to the living environment and then back again.

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21, May, 2023 0 Comments

Types of ecosystem | Structure of Forest Ecosystem | Function of Forest Ecosystem

Types of ecosystem of the world

In broad sense there are two major types of ecosystem namely terrestrial and aquatic. The terrestrial ecosystem is further divided into the following types of ecosystem-

Forest Ecosystem
Grassland Ecosystem
Desert Ecosystem.

Aquatic ecosystem is divided into two types of ecosystem-

Fresh water ecosystem
Marine or oceanic ecosystem.

The fresh water ecosystem is further divided into pond ecosystem, lake ecosystem, river ecosystem, and spring ecosystem.

Structure of Forest Ecosystem

There are two main components an found in this ecosystems.

(A) Abiotic Components – Forest ecosystem have the following abiotic components – soil, water, light etc.
(B) Biotic components – Forest ecosystem consists of the following biotic components.

1. Producers – All the green plants of a forest ecosystem is producers. They are the main sources of food for forest animals. The plants of a top substratum are angiosperm our and gymnospermous plants. They utilize radiant energy in the greatest extent. Below the level of tress there is a layer of srube and below of its the grasses, hobs, lichens and mosses are found. These plants get least light.

2. Consumers – There are a number of consumers in an old dense forest. Consumers of the first order in the forest are grasshoppers, rabbit, deer, monkey, bird and many other wild herbivores, which utilize plants directly as their food. Secondary consumers are walves, phythons, jackal, etc. which consumes the flesh of herbivores, and lion, tiger, hawks are the consumers of the top level.

3. Decomposers and Transformers – They are microorganisms, chiefly bacteria and fungi, which attack dead bodies of producers and consumers and convert couples organic material into simpler materials. These free simpler materials again return to the abiotic components and are reutilized by producers in their nutrition.

Function of Forest Ecosystem

The components of an ecosystem are connected in a complex web. Function of forest ecosystem includes following cycles –

1. Energy Cycle: The sun starts the food pyramid by feeling the photosynthesis process. Trees and green plants begin all life processes with photosynthesis and the resulting production of plant biomass.

The sun’s energy constantly changes form as plants covert light into plant biomass, which is then consumed by other organisms. Plants perform an important action of energy fixation, which is the basis for all life.

2. Water Cycle: The water cycle collects, purifies, and distributes the world’s water. Without the water cycle, life on earth would be impossible. Trees and plants are part of this water cycle. Transpiration is the controlled evaporation process by which plants lose H2O through the pores in their leaf structures. A full grown tree can transpire hundreds of gallons of water a day during growing season.

3. Nutrient Cycle: Trees rely on nutrients like phosphorous and nitrogen for healthy growth and reproduction. Throughout a tree’s life stages, they constantly use and return nutrients to the soil. Nutrient cycles regularly transform nutrients from the non-living environment to the living environment and then back again.

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21, May, 2023 0 Comments

Adaptation of Desert animals

Describe desert’s fauna adaptations in brief.

Desert animals are adapted to conserve moisture and escape heat of shimmering sun. They fall into following two categories:-

(a) Drought Evaders –

Drought evader xerocoles, like ephemeral plants, adopt an annual life style or go into cultivation or some other stage of dormancy. For eight or nine months, perhaps even several years, the eggs of insects and other invertebrates and insect pupae lie dormant. When the rain arrive and plants flourish, the deserts swarm with insects – crickets, grasshoppers, ants, bees, wasps, butterflies, moths, beetles, etc. going bear emerge from underground cells at the very time when the particular flowers

on which they feed are in flower. Some amphibians like spade foot toads aestivate for eight or nine months in an underground cell lined with a gelatinous substance that reduces evaporative losses through the skin. They appear on ground when the rain fall saturates the earth, move to the nearest puddle, mate and lay eggs. Young tadpoles hatch in 1% to 2 days, rapidly mature (15 to 45 days) and metamorphose into functioning adults capable of diging, their own retreats in which they aestivate until the next rainy season.

Birds nest during the rainy season, when food is most abundant for the young. If extreme drought develops during the breeding season, some birds do not reproduce. Keast (1959) has reported that among some. desert birds the endocrine control of reproduction depends on rainfall rather than day length. A few birds such as swifts, poorwills and humming birds become torpid when food is scarce small rodents such as kangaroo or pocket mice, aestivate during periods of most severe drought.

(b) Drought Resisters –

Drought resisters xerocoles are active whole year round and have evolved way of circumventing aridity and heat through morpho-physiological adaptations or by modifying their feeding and activity patterns (i.e. behavioural adaptations). Some animals simply avoid the heat by adopting nocturnal habits and remaining underground or in the shade during the day. Some desert rodents that are active by day periodically seek burrows and passively lose heat through conduction by pressing their bodies against the burrow walls. Some birds such as poor wills and humming birds and bats go into a daily torpor.

The large ears of some desert animals such as jackrabbits and kit fox may serves to reduce the need of water evaporation to regulate body heat. The ears may function as efficient radiators to the cooler desert sky, which on clear days may have a radiation temperature of 25°C below that of the animal. By seeking shade, where the ground temperature are relatively low and solar radiation is screened out, and sitting in depressions, where radiation from the hot ground surface is obstructed, the Lepus could radiate 5 kcal a day through its two large ears (400cm2). Such a radiation heat loss minimizes the heat loss through water evaporation (sweat glands).

The Kangaroo rat, which seals its burrow by day and thus keeps its chamber moist, can live throughout year without drinking water. Similar adaptation occurs in the jerboas and gerbils of Africa and the Middle East and the marsupial Kangaroo mice and Pitchipitchi of Australia. These animals feed on dry seeds and dry plant material even when succulent green plants are available. The kangaroo rat obtains water from its own metabolic process and from hygroscopic water in its food. To conserve water the animal remains in its burrow, by day, it possesses no sweat glands, its urine is highly concentrated and its faces is also dry.

Large desert animals such as the camel can use water effectively for evaporative cooling through the skin and respiratory system because their low surface-area-to body size ratio and lower internal heat production result in slower accumulation of heat. The camel not only excretes highly concentrated urine but can with- stand dehydration upto 25 per cent of body weight, and it loses water from body tissues rather than from blood. The camel accumulates its fat in the hump rather then over the body. This speeds heat flow away from the body and its thick coat prevents the flow of heat inward toward the body.

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19, May, 2023 0 Comments

4 Importance of Research

What are the four importance of research?

Importance of Research

The important of research are as follows:

(1) Basis for Government Policies:

Research provides the basis for Government Policies in all types of economic system. For example, Government’s budget is based on the analysis of needs and desires of the people and the resources available to meet these needs. Research helps us how the revenue can be raised for meeting the expenditure on the public needs. There are many alternatives for formulating and implementing the economic policies. The impacts of these policies are also studied with the help of research. The problems faced by cultivators, small and marginal farmers, cottage and small scale industries, large scale industries, trade unions, public distribution, Defence services are the matters where research is used and the solutions are found out. Thus in the context of Government policies research as a tool of economic policy is used to investigate economic structure with facts and figures diagnosis of events and predicting future developments.

(2) Solving Operational and Planning Problems:

Research has been playing an important role in solving various operational and planning problems of business and industry. Correct business decisions are taken with the help of operational research and market research along with motivational research which is based on human behaviour at work. Market research investigates the structure and development of market. It is used for formulating efficient policies for purchasing, production and sales. Operational research deals with the application of mathematical, logical and analytical tools to the solution of business problems of cost minimization or of profit maximization. Motivational research studies why people behave as they do. It determines the motivations underlying the consumer behaviour. All these are useful to the people who are responsible for business decisions in industry and business.

(3) Research solves Social Problems:

Research is useful for social scientists because it provides the intellectual satisfaction of knowing things which in turn increase the store of knowledge. Research is useful in social sciences for the sake of knowledge as well as the use of this knowledge in practical life. “This double emphasis is perhaps especially appropriate in the case of social science. On the other hand, its responsibility as a science is to develop a body of principles that make possible the understanding and prediction of the whole range of human interactions. On the other hand, because of its social orientation, it is increasingly being looked to for practical guidance in solving immediate problems of human relations.”

(4) Importance for Others:

Research has importance for others also They are:

(i) Those who are engaged in writing a Master’s or Ph. D. thesis, research is the basis of their career and it helps them in attaining high position in society;

(ii) Professionals are also engaged in research and for them it is a source of livelihood;

(iii) Philosophers and thinkers engaged in research are benefited and it provides new knowledge, ideas and insights;

(iv) Literary men and women get new styles and creative work from research methodology;

(v) New theories are generalized with the help of research which has importance for analysts and intellectuals.

In brief, we can say that research is the source of new knowledge which adds to the existing knowledge and an important source of providing guidelines for solving different problems in the field of business, government and society.

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19, May, 2023 0 Comments

What do you understand by Research? 6 Types of Research

What do you understand by Research?

Meaning and Definition of Research

Research is a part and parcel of human knowledge. Research in common sense of the term refers to a search for knowledge. It is matter of raising a question or problem and then trying to find its solution or answer. Research may be defined as a ‘careful critical enquiry or examination in seeking facts or principles; diligent investigation in order to ascertain something.’

It is a scientific and systematic search for pertinent information on a specific topic. It is an art as well as science of investigation.

The Webster’s International Dictionary has defined research as a careful critical enquiry or examination in seeking facts for principles, deligent investigation in “order to ascertain something”.

The Advanced Learner’s Dictionary of Current English defines research as “a careful investigation or inquiry specially through search for new facts in any branch of knowledge.”

Redmon and Mory have defined search as a “systematized effort to gain new knowledge.” Some people consider research as a movement which starts from the known situation and ends at an unknown situation. Research is based on some facts or on problems.

In modern times, research has become a corporate affair in which complex technique of collecting and processing data is used which results in generalization. It is used in a technical sense as it is an academic activity.

According to Clifford Woody, “research comprises defining and redefining problems, formulating hypothesis or suggested solutions; collecting, organizing and evaluating data; making deductions and reaching conclusions; and at last carefully testing the conclusions to determine whether they fit the formulated hypothesis.”

6 Types of Research

Researches have been classified into various categories depending upon the approach, the purpose and the nature of research activity, some basic types of research are given below:

(1) Descriptive and Analytical Research:

Descriptive research is based on surveys and fact-finding enquiries of different kinds. It is known as a questionnaire or opinion study. It studies the description of the state of affairs as it exists at present. It is used for identifying factors which are most promising for experimental investigation. The descriptive research studies are also known as ex-post-facto research in social science and business research. The basic characteristic of this method is that the researcher has no control over the variables. He reports what is happening or what has happened.

In analytical research, the researcher has to use facts or information already available. The information or facts are taken from various sources. The information or facts are analyzed by the researcher to make a critical appraisal of the material.

(2) Applied and Fundamental Research:

Research can either be applied or action research or fundamental or basic or pure research. Applied research is based on the application of known theories and models the actual operational fields. Under this type of research the problem is identified and the results are expected to be applicable in the improvement of the practice or solution to a problem producing material gains. It is used to find solution to an immediate problem facing a society or an industrial organization. Applied research has practical utility in developing economies. The testing theories can be applied in these economies with modifications.

Fundamental research is based on the theoretical knowledge and the logical process involved in the phenomenon. It pursues knowledge for the sake of knowledge itself. It studies the theories or principles as they are and thus it is a positive science. Gathering knowledge for knowledge’s sake is called pure or basic research. Research concerning some natural phenomenon is fundamental research whereas research aimed at certain conclusions facing a concrete social problem is an example of applied research. For instance, the theories related with the economics of development is fundamental research whereas the applicability of these theories for solving the problems of developing countries is applied research. However, it must be noted that the distinction between “pure research” and “applied research” is a matter of degree, and both can be said to be inter-dependent.

(3) Conceptual and Empirical Research:

Conceptual research is based on some abstract ideas or theories. This type of research is used by philosophers and thinkers to develop new concepts or to reinterpret existing concepts. Empirical research deals with experience or observation alone irrespective of system and theory. It is data-based research. The conclusions are verified by observation or experience. It is also known as experimental research. It presupposes precision and accurate observation. In experimental research independent and dependent variables are studied.

The former can be manipulated as an experimental variable in order to study the effect on the latter. Evidence based on experiments is considered to be the most powerful support possible for a given hypothesis.

(4) Quantitative and Qualitative Research:

Quantitative research is based on the measurement of the quantity of the phenomenon under study. It is the quantitative study of the phenomenon. The phenomenon is quantified and inferences are drawn by a researcher. Qualitative research, on the other hand, deals with the qualitative phenomena under study. For example, when we study the human relations approach in an organization for solving the problems through motivation research, we can say that this is qualitative research. The techniques which are used in qualitative research are association tests, sentence completion tests, story completion tests and other projective techniques. This type of research is generally useful in behavioural sciences where the object is to discover the underlying motives of human behaviour. The likes and dislikes of a person are found out. The task of a researcher in such a research studies is very complicated one and he should seek guidance from experimental psychologists.

(5) Survey and Evaluation Research :

Under survey research we study large and small populations by selecting and studying samples chosen from the population to discover the relative incidence, distribution and interrelation of sociological and psychological variables. The survey research can work well by resorting to sampling techniques. It is carried on through the methods of personal interviews, mailed questionnaires and personal discussions besides indirect oral investigations. This type of research is considered important these days because it makes a valuable contribution in the field of social sciences research methodology. A Evaluation research has recently developed.. It is a product of developmental programming which has been used on a large scale in recent years. This has developed after the Second World War with the emergence of the third world countries on the development the performance of the developmental projects and other economic programmes that have already been implemented at various governmental levels. It studies the real impact of such programmes on the people of the country. The evaluation research is carried on in three ways viz; concurrent evaluation, periodic evaluation and terminal evaluation. The researcher under this type of research should have the knowledge of the programmes and their process of implementation. It needs a scientific study of the problem.

(6) Other Types of Research:

Action research is also of a recent addition to the other types of research known to a modern social scientist. It is a research through launching of a direct action with the objective of obtaining workable solutions to the given problems. This type of research has the merit of adaptability according to changed population.

Historical research is based on the critical examination of past events or happenings in order to know the truth and later on, to generalization. George Bernard Shaw has rightly pointed out that, “the past is not behind the group. It is within the group.” Under this type of research reasoning is inductive. Historical sources like documents, remains etc. are used to study the events or ideas of the past by a researcher.

Research can also be either conclusion-oriented or decision-oriented. In case of conclusion-oriented research researcher is free to pick up a problem, redesign the enquiry as he proceeds and is prepared to conceptualize as he wishes. In case of decision-oriented research, it is based always for the need of a decision maker and the researcher is not free to embark upon research as he likes, Operation research is an example of decision-oriented research in which quantitative and scientific techniques are used.

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19, May, 2023 0 Comments

7 Salient Features of Research

Salient Features of Research

Research possess certain features which are given below:

(1) Logic and Objective : The purpose of any research is to find out facts. On the basis of these facts inferences are drawn. For example it is assumed that all vegetarian uneducated people in urban and rural areas have long life. On the basis of this assumption we can draw conclusion that vegetarianism is the cause of longevity. Objective means observing true picture of a phenomenon without being affected by observer’s own opinion. Reality is known through it.

(2) Verification : Any conclusion drawn by a researcher is subject to the quality of verification. Verification presupposes the phenomenon of research being observed and measured, if a research is not based on observation and measurement, the verification will not be possible and inferences drawn from such studies will not serve the purpose.

(3) Accuracy : Census or sampling methods are used in any type of research study. It should be based on accuracy. It is the duty of investigation that he should be well-versed with the techniques used for collecting information. Complete accuracy can be attained when standardized tools in collecting, recording and analyzing are used.

(4) Reliability and validity : Truth is the fountain of research. This can be established on the basis of evidence. Evidence is based on sufficient and reliable data. The reliability and validity can be attained when the error of bias or sampling is minimized.

(5) Recording and Reporting : In any research every term is well defined; every procedure is described in detail, every limiting factor is taken into account. References used in research are carefully documented and the results drawn in the field of research are objectively recorded. Conclusions and generalizations are drawn with care with the limitations of methodology and data. When all these things are well-recorded, they can be used as a source of investigation for further research in future.

(6) Impartiality : The problem of impartiality is a part of the problem of objectivity. Knowing reality is based on the correct method dealing with logic. Partiality leads to wrong information and it fails to give fruitful results to the investigator.

(7) Scientific Approach : Traditional culture was based on superstitions and there was lack of scientific integrity. Modern culture is based on scientific attitude and scientific method of approach. Changing dimensions of scientific progress has led to the scientific research through which an instrument of reliability has been attained. There has been an advancement of knowledge.

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19, May, 2023 0 Comments

Sources of Research Problems | Criteria of a Good Research Problem

Sources of Research Problems

The Research problems may be selected from the following sources :

(1) Theory of one’s own interest : A researcher may select a problem for investigation from a given theory in which he has considerable interest. In such situations, the researcher must have a thorough knowledge of that theory and should be sufficiently inquisitive to explore some unexplained aspects or assumptions of that theory.

(2) Technological changes : Technological changes impact the society and are constantly bringing up new problems as well as opportunities for research. The impact of a changing technology on the existing socio-economic set-up, always interests the researcher and tempts him to undertake such studies which reveal the impact of new technology on the existing system.

(3) Daily problems : The problem can also be selected on the basis of the daily experiences of a researcher. Every day, problems constantly present something new and worthy of investigation and it depends on the sharpness of the researcher’s intellect who can convert his daily experiences into a research problem.

(4) Unexplored areas : Research problem can also be selected from those areas which have not been explored so for. Such areas may be theoretical or empirical in nature. For example – An economical analysis of hill farming systems in a region where such an investigation has not been undertaken earlier is a useful piece of research. In a similar fashion, many geographical regions about which no knowledge exists can easily be undertaken for research purposes.

(5) Discussion with the research advisor : The advisor must provide all resources, needed at the time and the student should be directed to proceed along proper lines, wherever necessary. The Advisor must guide the students to select appropriate projects and must encourage the students to aim at completion.

Criteria of a Good Research Problem

A good problem selected by the researcher should conform to the following criteria, namely :

(1) Importance : It should be significant enough and involve an important principle or practice. If it is not worthwhile, or one that, neither adds to knowledge nor leads to any improvement in the current practices, then, it would be in vain.

(2) Relation between variables expressed : The problem should express a relation between two or more variables.

(3) Empirical verification : The problem should be such as to simply possibilities of empirical testing. This means not only that an actual relation is stated, but also that the variables of the relation can somehow be measured.

(4) Availability of guidance : Every research activity needs the patronage of a guide and the approval and sanction of a competent authority.

(5) Level of research : The nature and scope of a study will be determined in the light of levels like Master’s Degree, M. Phil Degree and Ph.D. It may simply be an action research or a research to produce a research paper or an experimental project.

(6) Interesting : The problem should be interesting for the investigator himself. His interest should be purely intellectual and should not be only for a reward, material benefit, advancement in position, increased authority, and so forth.

(7) Novelty : It should be sufficiently original, so that it does not involve objectionable duplication.

(8) Clarity and unambiguity : The problem should be related clearly and unambiguously in a question form.

(9) Experience and creativity : Good research problems start from a clear understanding of the theoretical, empirical, and practical aspects of the subject derived from personal experience.

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17, May, 2023 0 Comments

What is meant by Research Process? 11 Steps of Research Process

What is meant by Research Process? Explain the Various steps or Process involved in research process.

Meaning of Research Process

The research process consists of a number of closely related activities starting from “Define research problem” to “Interpret and report,” A researcher should know that the various steps involved in a research process are not mutually exclusive nor are they separate and distinct. He should know the requirements of each step and subsequent steps.

11 Steps of Research Process

A brief description of the various steps of research process is given below:

1. Formulating the Research Problem:

The first step of research process is to define the research problem. Research problems are of two types, viz. those which deal with the state of nature and others are related to deal with relationships between variables. A researcher has to single out the problem he wants to study. He should be aware of the general area of interest or the subject matter that is to be enquired by him. In formulating the research problem the researcher should understand the problem in depth and the same has to be rephrased into meaningful terms from an analytical point of view. The best way of understanding the problem is that a researcher should discuss it with his colleagues as well as with some experts in the field. In an academic institution the researcher can seek the help from his guide who has ample experience in the field of research and has many research problems in his mind, Generally, the guide puts forth the problem in a general way and it is the duty of the researcher to narrow it down and have the shape which can be used in operational terms. In private business firms or Governmental organizations, the research problem is earmarked by the administrative agencies. The researcher should discuss various aspects of the problem with these agencies. He should examine all available literature to get himself acquainted with the selected problem. He has to review two types of literature, viz. conceptual literature related with concepts and theories and review the literature based on previous research findings. This review of literature will be helpful to the researcher to know as to what data and other materials are available for operational purposes. The task of defining or formulating a research problem is the most important step in the research process. The problem to be investigated must be defined with exactness and must be of relevant use, otherwise the research process will be unmanageable.

2. Extensive Literature Survey:

After defining the research problem a researcher has to conduct an extensive literature survey for writing a brief summary of it. It is compulsory for a researcher writing a thesis for M. Phil. or Ph. D. degree to write synopsis of the topic and submit it to the Research Committee or Board for obtaining the approval. At this juncture the researcher should undertake an extensive literature survey connected with the research problem. For this purpose abstracting and indexing journals and published or unpublished bibliographies, academic journals, conference proceedings, government reports, books etc. are used. The earlier studies, which are similar to the study in hand should also be carefully studied. A good library will be an important source to the researcher at this stage.

3. Formulation of Hypothesis:

After reviewing concepts and theories and reviewing previous research findings, the researcher should state clearly the working hypothesis. Working assumption is an assumption on the basis of which inference are drawn and tested logically. The manner in which research hypothesis are developed is of great importance because they provide the focal point to a researcher. The tests, analysis of data, quality of data depend on such hypothesis. Hypothesis should be very specific and limited to the piece of research in which a researcher is engaged because it has to be tested. Hypothesis provides the guidance to the researcher. His area of research is clearly defined. Hypothesis indicates the type of data required and the type of methods of data analysis to be used.

The following approach is used by a researcher for developing working hypothesis:

(i) Problem is discussed with colleagues and experts, its objectives and the objectives in seeking the problem;

(ii) Available data and records are examined to know possible trends, peculiarities and other clues;

(iii) Review of previous research findings in the area;

(iv) Exploratory personal investigation is carried on with original field interview on a limited scale which will provide greater insight into the practical aspects of the problem.

Thus working hypothesis arises as a result of thinking about the research problem, examination of the available data and material, including related studies and the guidance of experts in the field. Hence the working hypothesis should be stated in precise and clearly defined terms.

4. Preparing the Research Design:

Once the research problem has been formulated in clear cut terms, the researcher has to prepare a research design. The well prepared research design will provide maximum information to the researcher. It will provide a basis for the collection of relevant evidence with minimal expenditure in terms of time, money and energy. But the achievement of all these depends mainly on the purpose of a research problem. The research purposes are of varied in nature. They may be of four types viz.: (i) Exploration, (ii) Description, (iii) Diagnosis and (iv) Experimentation. While preparing the research design the research should keep in his mind the purpose of problem under study.

There are different types of research designs, such as experimental and non-experimental hypothesis testing. Again experimental design may be either informal or formal design out of which the researcher has to select one for his own research project.

5. Determining Sample Design :

All the items under consideration in any field of Inquiry constitute a universe or population. In a census enquiry all the units of a universe have to be studied whereas in a sample enquiry only selected numbers of units are observed and conclusions are drawn about the universe from their study. Many difficulties are generally faced in a census enquiry, particularly when the field of enquiry is large. A large sample enquiry is more adaptable than a census, because in it a small number of trained investigators can collect the whole data whereas in census enquiry a large army of investigators may have to be appointed. Besides this, a sample enquiry needs less time, money and energy. It is much more scientific than a census enquiry because in it the extent of reliability of the results can be known whereas this is not always possible in census enquiries. In many cases census enquiry is not possible in practice.

For example, blood testing is done only on sample basis. There is also belief that the larger is the size of the sample inspected the better is the idea obtained about the enquiry. The items so selected constitute what is technically called a sample. The researcher must decide the sample design. It is a definite plan determined before any data are actually collected for obtaining a sample from a given universe. Thus, the plan to select 12 of a city’s 200 whole sellers in wheat in a certain way constitute a sample design. Samples can be either probability samples or non-probability samples. In case of probability samples each element has a known probability of being included in the sample. Contrary to it, non-probability sample do not allow the researcher to determine this probability. Probability samples are of various categories. They are based on simple random sampling, systematic sampling, stratified sampling, cluster sampling while non-probability samples are based on convenience sampling, judgment sampling and quota sampling techniques.”

6. Collecting Data:

The next step in research design is to collect data for the problem under study by a researcher. In case of real life problem data at hand are inadequate and hence, it becomes necessary to collect data that are appropriate. There are several ways of collecting such data depending upon the researcher in terms of money costs, energy and time. Primary data are collected either through experiments or through survey method. If the researcher conducts experiments, he observes some quantitative measurements, with the help of which he examines the truth of his hypothesis. In case of survey method data are collected by any one of the following ways:

(i) By Observation: Under this method of survey investigator collect information on the basis of his own observation without interviewing the respondents. The information so collected is based on the present happening of events and influenced by either the past behaviour or future attitudes of respondents. This method is not suitable in enquiries where there are large samples.

(ii) Through Personal Interviews: The investigator follows this method to collect the information personally from the sources concerned. He should put easy and simple questions which are capable of being answered precisely and in a language which is not vague. This method is suitable only for intensive investigations. It involves enormous cost and usually requires a long time. This method suffers from the bias or prejudice of the investigator.

(iii) Through Telephone Interviews: Under this method information is collected from the respondents on telephone itself. It is not a widely used method. It is useful in those cases where the time is limited and the area under survey is important and well-developed. Industrial surveys in developed regions are examples of such method.

(iv) By Mailing of Questionnaires : Under this method questionnaires are mailed to the respondents with a request to return after completing the same. The researcher and respondent do not come in contact with each other. This method is generally used in economic and business surveys. Success in this method depends on the cooperation that the informants are prepared to give. Sometimes due to indifferent attitude of informants, questionnaires are not returned to the researcher. Questionnaire should be prepared very carefully so that it may prove to be effective in collecting the relevant information.

(v) Through Schedules: Under this method enumerators are assigned the duty of data collection by filling up the schedules. The selection of enumerators is very important task and should be carefully done. They should be explained the nature, scope and subject of the investigation thoroughly and they should properly understand the implications of the different questions put and definition of the various terms used. Dr. A. L. Bowley has rightly pointed out that in the collection of statistical data commonsense is the chief requisite and experience the chief teacher.

7. Execution of the Project:

Once the data collection is accomplished the project is executed. If the project is properly executed on correct lines the data to be collected would be adequate and dependable. It is the duty of the researcher that the project is executed in a systematic manner in time. If the survey is based on the questionnaires, data can be easily processed. In such a situation, questions as well as the possible answers may be codified. If the data are to be collected through interviewers, arrangements should be made for the selection and training of the interviewers. Thus steps should be taken to ensure that the survey is carried on under statistical control and standard of accuracy is maintained.

8. Analysis of Data:

Once the data have been collected, the researcher has an important task of analyzing them. The analysis of data requires a number of operations such as establishment of categories, codification of data, tabulation and then drawing statistical inferences. Collected data are classified, serialized and tabulated. The process of arranging data in groups or classes according to resemblances and similarities is technically called ‘classification of data’ that should be unambiguous, stable and flexible. Classification of data is also done according to class intervals which involves three basic problems such as, number of classes and their magnitude, choice of class limits and counting the number of each class. If two variable quantities can be arranged side by side so that the measurable differences in the one correspond to the measurable differences in the other, the result is said to form a statistical series. These series can be of three types viz. Time series, spatial series and condition series. An orderly arrangement of data in columns and rows is called tabulation. Tabulation may be simple or complex, one-way tables, two-way tables, three-way tables and higher order tables. A great deal of data, specially where the size of sample is large, is tabulated by computers. Computers save time and they make possible the study of a large number of variables affecting a problem.

9. Hypothesis Testing:

After the analysis of data the next research process starts with testing of hypothesis. Researcher has to test the hypothesis with the facts he has collected and come to conclusion whether the facts support the hypothesis or that is contrary to these facts. For testing hypothesis various statistical tests have been developed such as chi-square test, t-test, F-test. The hypothesis can be tested by the researcher through the use of one or more of such tests, depending upon the nature and object of research problem. Such testing results in either accepting the hypothesis or in rejecting it.

10. Generalization and Interpretation:

If a hypothesis is tested and accepted several times, it becomes easy for each researcher to arrive at generalization and on the basis of generalization a theory can be built. In practice the real value of research is found when the researcher comes to generalization with the help of his research techniques. If a researcher has not built any hypothesis for the research problem he may explain his finding on the basis of some theory. It is called interpretation.

11. Preparation of Report:

The last stage of research process is the preparation of the report or the thesis. It is prepared by the researcher on the basis of what he has done in the study of research problem. The following things should be kept in mind by the researcher while preparing the report:

(i) The layout of the report should consist of the preliminary pages, the main text and the end matter. In the preliminary pages of the report title, date, acknowledgements and foreword are included. Then there should be a table of contents followed by a list of graphs and charts as given in the report.

The text of the report consists of the following parts:

(a) Introduction: It deals with the objective of the research and explanation of the research methodology adopted. The scope of the study and its limitations are also discussed.

(b) Summary of Findings: After introduction a statement of findings and recommendations is described.

(c) Main Report: This part of the report is presented in logical sequence and it is divided into various identifiable sections.

(d) Conclusions: At the end of the main text researcher should present the results of his research clearly and precisely. At the end of the report appendices of technical data, bibliography of books, journals, reports etc. are enlisted.

(ii) Report should be written in a concise and objective style. It should avoid vague expressions such as ‘it seems’ ‘there may be’ etc.

(iii) If the information has to be presented by the researcher more clearly and forcibly, charts and illustrations should be given.

(iv) The report should also throw light on the constraints experienced in conducting research operations by a researcher.

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13, May, 2023 0 Comments

Ecological succession : Meaning, Types, Causes, Trends and Process

Define succession.

Meaning of Ecological succession

Ecological Succession: Ecological succession is defined as a continuous, unidirectional, sequential change in the species composition of a natural community. This sequence of community is termed as sere and culminates in the climax community. Early successional stages are characterized by pioneer species, low biomass and often low nutrient levels. Community complexity increases as succession progress, often peaking in the mid-successional stage. A mid-successional community is characterized by high biomass, high levels of organic nutrients and high species diversity.

Odum (1969) has given the following three main characteristics of succession:

(i) Succession is an orderly process of community development that is reasonable directional and therefore predictable.

(ii) Succession is community induced process and organisms bring for modifications in the physical environment determine the pattern and rate of succession within the habitat.

(iii) Succession leads to the formation of a stabilised community with maximum biomass, species diversity and of all possible niches by the organisms. The development in ecological succession begins with:

(a) Formation of Soil: Development of soil occurs with addition of soil layers, loosening soil and plus organic matter. In this way a soil prepares itself for plants.

(b) Development of Plants: Generally single autotrophic cells are pioneer community. This refines soil molecules to name still evolved plants.

(c) Development of Community: Increased plant population enhances the rate of soil formation and addition of organic matter. It also helps in commencing a community.

(d) Development of Microclimate: The micro environment also gets itself established in the community as the density of the same increases.

(e) Species-diversity: Gradually more species inhabit into the area and a richer community grows.

(f) Change in Population: The pioneer or short lived population are replenished by other population which are longer lived.

(g) Appearance of Climax Community: The sequential change in population reaches to climax community. This is richer and dominant community. It also maintains an equilibrium with environment.

Types of succession

Some basic types of succession are as follows –

(a) Primary Succession: When Succession begins in an area which was not preoccupied by any community or population it is known as primary succession. The areas like a exposed rock are underearth, sand dunes, new emerged islands, deltas, shores etc. The first in habitating groups of organisms are pioneer community.

(b) Secondary Succession: Secondary succession begins in an area where at sometime a community existed i.e. nutrients, conditions for survival are already present, e.g., river banks after flood, cut over forest, abandoned cropland and ploughed field, earth after famine. This type of succession is rapid and do not have to start from beginning. So presence of some organisms and the respectability of territory enhance the development of community.

(c) Autogenic Succession: After the succession has begun, most of the cases, it is the community itself which, as a result of its reactions with the environment, modifies its own environment and then causing its own replacement by new communities. This course of succession is known as autogenic succession.

(d) Autotrophic Succession: It is characterised by early and continued dominance of autotrophic organism like green plants. It begins in a predominantly inorganic environment and the energy flow is maintained indefinitely. There is gradual increase in the organic matter content supported by energy flow.

(e) Allogenic Succession: In some cases, however, the replacement of the existing community is caused largely by any other external condition and not by the existing organisms. Such a course is referred to as allogenic succession.

(f) Heterotrophic Succession: It is characterised by early dominance of heterotrophs, such as bacteria, actinomycetes, fungi and animals. It begins in a predominantly organic environment, and there is a progressive decline in the energy content.

Patterns of Succession

There are three patterns of succession which are differentiated by the presence or absence of moisture. The types are hydrosere (in water), xerosere (in dry conditions) and mesosere (adequate water availability).

(a) Xerosere: The xerosere succession begins on bare rocks, sands, rocky slopes or areas with extreme deficiency of water. The stages of the succession are as follows-

(i) Lichen stage: The pioneer community of xerosere is lichen. These are able to withstand extremes drought conditions and flourish rapidly. The first lichen to appear is generally crustose lichen like Rhizocarpon, Rinsodina etc.

These lichens gradually disintegrate rocks into soil. These add small particles and dead organic matter to newly formed soil. When a thin soft layer of soil appears, crustose lichens are replaced by foliose lichens. Foliose lichens have bigger leaf like thallus which cover crustose lichen and hence the latter gradually give way. The foliose lichens are namely Dermatocarpon, Parmelia, Umbilicana etc. As foliose lichens are grown in size, these add more humms to soil.

A few mites, spiders, appear in the community as cracks and crevias develop in rock.

(ii) Moss Stage: Adddition of humms and dust alters the environment and moss appear in community. Tortula, Barfula and Grimnia byrum show up first later comes Funaria, Polytrichum and Sphagnum. Increase in variety of mites, spiders is noted with development of moss.

(iii) Herbaceous Stage : As the carpet of moss expands more soil is produced and much humms is made. Winds also blow’s and which get collected around moss as dust and thus minerals are also added Weeds often perennial grasses appear first. The broom grass Andropogon dominates.

In the altered environment nematodes, larval insects, collembola, ants and mites mark their presence.

(iv) Shurb Stage: With the advancement of time shrubs over power herbs. The changed environment also enhances growth of shurbs and perennial wood plants such as Acacia, Capparis, Prosopis, Zizyphus etc.

Now carnivorous approach in the community many birds, insects, rodents, reptiles mammals inhabit the territory.

(v) Climax Forest: The shrubs give appropriate atmosphere for forests. In shrubs community trees are less in number, As the number of trees increase more fauna appear and a complex stable community appears.

(b) Hydrosere: The hydrosere succession commence with freshly formed pond. There is abundance of water, hence succession starts from aquatic life.

(i) Submerged Stage : Life in ponds begins with phytoplanktona and zooplanktons. As no other population is present these planktons flourish and water is laden with many organic compounds. This increase in organic matter enhances other submerged plants to grow the pioneer submerged plants are Vallisneria, Utricularia, Ceratophyllum, Potamogeton etc.

Death of these plants furnish water with added layer of organic matter and nutrients. Among animal some lower chordates and molluses invade the water first.

(ii) Floating Stage: Floating plants enter in the picture when the depth of water is lesser. Among floating plants the first to show up are Monocharia, Nelumbiun, Nymphaea, and Trapa etc. These plants bear floating edges and their roots are at the bottom of pond. Later free floating plants, e.g., Azolla, Lemna and Wolffia make there way in. Molluscs, fishes increase in variety among animals.

(iii) Reed-swamp Stage: The water get shallower with the invasion of more organisms and deposition of more organic water and water evaporation through transpiration. As the water level drops, the pond becomes unsuitable for submerged or free floating plants. Now the reed swamp appear at shores. Thypha, Rumex and Sagittaria. The shore inhabitants gradually descend into pond and fill it with patches. The mud from banks also add to decrease water level. Among animals beavers and muskrats also appear with molluscs and amphibians.

(iv) Marsh-meadow Stage: Due to continuous addition of layers of organic matter and soil the place becomes saturated. The shrubs and herbs appear at edges and gradually cover the whole area.

(v) Woodland Stage: The shrubs and herbs progressively reach for the trees. Thus the flora approaches a forest look. Similarly constant change in fauna is also noted. The fauna changes from aquatic to amphibian then to terrestrial vertebrates.

(c) Mesosere: Succession in a mesosere environment is rapid. The initial adverse conditions found in xerosere and hydrosere are not be overcome. Hence this type of succession is mostly found in secondary succession.

Climax Community of Succession

A well balanced and stable community ends up succession, this community is known as climax community.

The initial changing in environment makes itself stable with change in populations. Thus a steady population have an equilibrium between birth and death of organisms. This balance is also maintained for energy ie. the intake of energy by a community is restored in nature. This constant stage of community as a system is known as dynamic equilibrium or steady state. Hence climax refers to steady state in a naturally existing community.

Theories of Succession

The climax community is always not in a singular form i.e. the number of climax communities made ecologists to define climax communities.

(i) Monoclimax Theory: American ecologist Fredrick Clements postulated that there is only one climax community in a given climatic or geographical region. But in nature it is not always so. The type of soil and climatic zone ends up into different communities. These are known as subordinate community and the terms preclimax, subclimax, disclimax and postclimax are types of subordinate community.

Proclimax or preclimax community is nearby to climax i.e. it is quite stable and resembles climax community in many respects. When it is rampaged by human or animals the same is disclimax, e.g., grassland in forest due to excessive tree cutting. If a developing community is stowed down or stopped due to natural calamities it is called subclimax or preclimax. Whereas at times a belt or a zone in an area develop extra ordinarily good, e.g., a forest in grassland community. It is called postclimax community.

(ii) Polyclimax Theory: European ecologist Nicholos, Champion, Bore and Whittaker stated that a number of climax community may be present in a given area. These opined that preclimax, postclimax, subclimax etc. are all climax communities as they are self sustaining.

(iii) Climax Pattern Theory: This theory pronounce that climax communities are determined by the total environment of the ecosystem and just not by a single factor. Thus it can be represented by a pattern of animals which have intimate relationship with flora and fauna of ecosystem. A single plant or animal cannot survive on its own only. Even the soil and climate play an important role in forming a climax community. This theory gathers much vote and support from present ecologists.

Causes of Succession

Generally there are three types of causes:

1. Initial or Initiating Causes – These are climatic as well as biotic. The former includes factors, such as erosion and deposits, wind, fire etc. caused by lightning or volcanic activity and the latter include the various activities of organism.

2. Ecesis or Continuing Causes – These are the process as migration, ecesis, aggregation, competition, reaction etc. which cause successive waves of population as a result of changes, chiefly in the edaphic features of the area.

3. Stabilizing Causes – These cause the stabilization of the community.

General Process of Succession

The whole process of a primary autotrophic succession is actually completed through a number of sequential steps. These steps are as under:

1. Nudation – This is the development of a bare area without any form of life. The area may develop due to several causes such as landslide, erosion deposition or other catastrophic agency. The cause of nudation may be topographic, climatic, biotic factors.

2. Invasion – This is the successful establishment of a species in a bare area. The species actually reaches this new site from any other area. This whole process is completed in following three successive stages:

(i) Migration
(ii) Ecesis
(iii) Aggregation.

3. Competition and Coaction – After aggregation of a large number of individuals of the species at the limited place, there develops competitions mainly for space and nutrition. Individuals of a species affect each others life in various ways and this is called coaction.

4. Reaction – The mechanism of the modification of the environment through the influence of living organism on it, is known as reaction.

5. Stabilization. Finally, there occurs a stage in the process, when the final terminal community becomes more or less stabilished for a longer period of time and it can maintain itself in equilibrium with the climate of the area. The final community is not replaced, and is known as climax community and the stage is called climax stage.

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11, May, 2023 0 Comments

9 Main Physiological Adaptation to Marine Life

Physiological Adaptation to Marine Life

1. Stream-lined Body – The body shape is stream-lined like primarily adapted forms: neck construction disappears and tail enlarges, e.g- Ichthyosauria (extinct fish-lizard), Cetacea (whales, dolphins, porpoises), Sirenia (manatees and dugongs), Pinnipedia (walrushes and seals). Frog also contains stream-lined body.

2. Enlargement of Size – Aquatic vertebrates tend to be larger in size because in these creatures energy, which in terrestrial from is exhausted in gravitational forces, is turned into growth. For example, largest sulphur- bottom whale (balaenoptera musculus) is several times bigger than the largest elephant. Other example include giant sharks and squids.

3. Shortening of Neck- These occurs reduction of length and mobility of neck. In whales cervical vertebrae (which are seven in number like other mammals) are fused to form a solid and compressed mass of bone.

4. Mouth Armament – Since jaws are not used for mastication in whales they lost the power of movement. Teeth become simplified (homodont in dolphins) and greater in number. In sperm whole, teeth are present only on one jaw or entirely absent from both the jaws (baleen whale).

5. Skull Modification – In certain aquatic mammals (dolphins, propoises) the cranium is shortened and front part of the skull becomes elongated to acquire the shape of a rostrum. In the skull of the cetacea, the zygomatic arch is reduced to a vestige.

6. Simplification of Vertebrae – In secondary aquatic forms the vertebrae tend to be simple. In Ichthyosaurs, Vertebrae are simple with biconcave centra like the fishes. Various secondary articulations or zygapophysis become reduced, as body weight is supported by water. The chest too become cylindrical. The rib articulations are modified and are central, i.e. they are articulated to the centrum and are not articulated to the transverse processes.

Sacrum in cetaceans and sirenians is more or less reduced, since it does not with stand and transmit the supporting impact of the hindlimbs, as does in terrestrial forms.

7. Lightness of Bones – The bones in aquatic forms are light and spongy. In wholes, their interstices are filled with oil.

8. Disappearance of Hairs, Skin Glands – In whales and sirenians, the skin becomes makes due to loss of hairs. The hair loss is compensated by the formation of a fatty layer below the skin (blubber) for the retention of the bodily heat. The blubber also has a hydrostatic advantage.

9. Occurrence of Locomotory Paddles (Fins) – There occure fleshy and fin-like expansions of the body wall in whales and ichthyosaurs which help in propulsion. These fins may be dorsal or caudal. Dorsal fin is present in killer whale, while absent in Delphinopterus and Balaena. Caudal fin (also called caudal or tail fluke) of marine mammals in horizontal and the bone divides the tail into two equal parts rather than running into one lobe. In tulles oar propulsion occurs by fin-like limbs, but in whales, sirenians etc. tail propulsion takes places as their hind limbs become disappeared.

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