29Nov 2018 by admin

Short Speech on Sense Organs

Environment
The sense organs or the receptors are structures specialized to perceive conditions outside and to some extent inside the body, and these provide the information to the central’ nervous system upon which action may be taken.In some cases the stimuli act on special cells which may be grouped into organs, while in others the ends of nerve fibres appear to be sensitive. ADVERTISEMENTS: The sense organs are in no way responsible for the sensations because the power of sensation is res­tricted only in the central nervous system, these serve merely as avenues of approach to central nervous system.Sense organs are of common occurrence from invertebrates to vertebrates. In protozoans they are represented by pigment spots which are sensitive to light. Image Source: i.ytimg.comIn arthropods sensilla represent the simple types of…
Read More
29Nov 2018 by admin

What is the Difference between “Private Cost” and “Social Cost”? – Explained!

Air Pollution
Private Cost: Private cost refers to the cost of production incurred and provided for by an individual firm engaged in the production of a commodity. It is found out to get private profits.This cost has nothing to do with the society. It includes both explicit as well as implicit cost. A firm is interested in minimising private cost. Image Source : sustainablejill.com Social Cost: ADVERTISEMENTS: Social cost refers to the cost of producing a commodity to the society as a whole. It takes into consideration all those costs, which are borne by the society directly or indirectly. Social cost is not borne by the firm. It is rather passed on to persons not involved in the activity in the direct way. Social cost is a much broader concept.It is found…
Read More
28Nov 2018 by admin

20 Multiple Choice Questions (MCQs) with Answers on Energy

Environment
1. Which of the following is a non-renewable resource?(a) Coal(b) Forests ADVERTISEMENTS: (c) Water(d) Wildlife Image Source: i.ytimg.com2. Which among the following is not a renewable source of energy? ADVERTISEMENTS: (a) Solar energy(b) Biomass energy(c) Hydro-power(d) Geothermal energy ADVERTISEMENTS: 3. Identify the non-renewable energy resource from the following:(a) Coal(b) Fuel cells(c) Wind power(d) Wave power 4. Which of the following is a disadvantage of most of the renewable energy sources?(a) Highly polluting(b) High waste disposal cost(c) Unreliable supply(d) High running cost5. Photovoltaic energy is the conversion of sunlight into:(a) Chemical energy(b) Biogas(c) Electricity(d) Geothermal energy6. Horizontal axis and vertical axis are the types of:(a) Nuclear reactor(b) Wind mills(c) Biogas reactor(d) Solar cell7. Which among the following is not an adverse environmental impact of tidal power generation? (a) Interference with spawing…
Read More
28Nov 2018 by admin

33 Objective Type Questions (MCQs) with Answers on “Environmental Pollution”

Air Pollution
1. Which of the following is an air pollutant?(a) Nitrogen(b) Carbon dioxide ADVERTISEMENTS: (c) Carbon monooxide(d) Oxygen Image Source: abctechnolab.com2. Which of the following is a secondary air pollutant? ADVERTISEMENTS: (a) Ozone(b) Carbon dioxide(c) Carbon monooxide(d) Sulphur dioxide ADVERTISEMENTS: 3. The environmental lapse rate is found to be:(a) – 6.5°C/km(b) 8.6°C/km(c) 6.5°C/km(d) 5.6°C/km 4. During Inversion:(a) Temperature increases with altitude(b) Temperature decreases with altitude(c) Temperature remains constant(d) None of the above5. Among the following, the only secondary pollutant is: (a) Sulphur tetraoxide(b) Sulphur dioxide(c) Ozone(d) Sulphur tetraoxide6. Which of the following groups of plants can be used as indicators of SO pollution of air?(a) Epiphytic lichens(b) Ferns(c) Liver worts(d) Horn worts7. Which of the following on inhalation dissolved in the blood hemoglobin more rapidly than oxygen?(a) Sulphur dioxide(b) Carbon mono-oxide(c)…
Read More
26Nov 2018 by admin

6 Main Features of Depository System

Environment
Depository system is a system wherein the securities of investors are held in the electronic form with the depository at the request of the investors and transfer of securities takes place by means of book entries on the ledger of the depository. The system is also referred as the ‘scrip less trading system’ as the system dispenses with the securities and its movement in the physical form.The depository system provides for the establishment of depositories to curb the irregularities in the capital market and protect the interests of the investors. The system facilitates an orderly conduct of the financial markets through the free transferability of securities with speed, accuracy and transparency. ADVERTISEMENTS: Main Features of “Depository System” are: 1. Securities in Dematerialised Form: Depository system provides for maintenance of ownership…
Read More
25Nov 2018 by admin

863 words essay on Man and Environment (Free to read)

Ecology
Free sample essay on Man and Environment. Our environment is really unique because it sustains life and growth. On other planets there is no environment and, therefore, no life.Environment means all that surrounds us. It is a very complex and comprehensive phenomenon. It consists of the climate, geography, geology and all the natural resources that nature has bestowed upon us. Life is there because of our peculiar biosphere and ecosystem. There is life on this planet because of a certain balance between these various elements. Without this balance, our planet would have been just another sterile and lifeless planet revolving round the sun.Our life depends on healthy and balanced environmental conditions. Our health, working habits, lifestyle, and behaviour, etc. are closely linked with all that surrounds us. The climate is…
Read More
23Nov 2018 by admin

351 Words Essay on Population – Good or Bad for India

Global Warming
India is the second most populous country in the world. This has its positive and negative aspects. The positive aspect is that most of the people in this country are below 25. This means that we don’t have to fear for our economic productivity unlike countries like Japan where there are more retired people than young people. This graying of the population spells doom for Japan’s economic growth as it won’t have enough young and healthy people to work in its offices and factories. It will have to import labor from other countries to take up these jobs. The negative aspects far outweigh the positive aspect of a sizeable population. Overpopulation strains the natural resources of a country. People migrate from villages to cities in search of better opportunities leading…
Read More
23Nov 2018 by admin

487 Words Essay on Pollution (free to read)

Air Pollution
“What is pollution? Dictionary defines that the process of making Air, Water, Soil, etc. dangerously dirty and not suitable for use! Pollution plays havoc in man’s life. Pollution can be classified into many groups.Air Pollution:When fresh air gets mixed up with any one of these, like smoke emitted by vehicles, Industrial smoke, Fires, Dust storm, explosions, burning of waste, bombs and crackers, it kills the oxygen content in the air and become dangerous to inhale. It amounts to sickness like Lung cancer, Asthma and many others. ADVERTISEMENTS: At times, it may be fatal too. One may recall the leakage in the poisonous gas cylinder in the Union Carbide company in Bhopal that killed some hundreds of people and the cattle.Similarly, the twin atomic bombs dropped on Hiroshima and Nagasaki by…
Read More
23Nov 2018 by admin

466 Words Essay on Natural Disasters (free to read)

Disasters
Sky, land, Water, Fire and wind – these five according to Hindu mythology is referred to as Mother Nature and worshipped, because many disasters to mankind occur due to these five reasons. Some of die major disasters like Earth quake, Fire, Hurricane, Volcanoes and Flood add woes that no amount of scientific advancement could prevent them.Earth Quake: ADVERTISEMENTS: It is caused due to tectonic plates jolt past each other that send shock waves! It never comes in single. A few minor tremors occur both before and after an intense burst. Its intensity is measured in Richter scale.At times, it kicks up a tsunami, like the one that happened 011 Dec. 24, 2004 in India and few of its sub-continents killing over 1,20,000 people and destroyed property worth trillions of dollars.…
Read More
21Nov 2018 by admin

501 Word Essay on Lightning and Static Electricity

Air Pollution
Lightning is a discharge of static electricity in the atmosphere, which causes a bright flash of light. When lighting goes through the air, it heats the air. This heating causes the air to expand and contract. This causes the sound called thunder.Lightning is caused by a buildup of negative ions in the atmosphere which discharges into the ground causing the negative ions to go with the positive ions in the ground. Static electricity is negatively and positively charged atoms. A static charge on the other hand is an individual atom with a negative Positive charge.There are three types of charges negative positive and neutral. Negative and positive ions attract. But the negatives repel each other, just like two positives will. Image Source : i.ytimg.com ADVERTISEMENTS: Neutrally charged ions can attract…
Read More