Unit-7→Ecology And Environment

Introduction:

Ecology is the branch of science that deals with the relationship between the organism and the environment. There are different levels of organization, such as:
• Organism – each individual of the species
• Population – It is defined as group of organisms that can interbreed
• Communities – Different population combine to form communities
• Biomes – Large unit of flora and fauna in a specific climatic zone
All the organisms have the ability to adapt via the process of biological variation in order to adjust with their environment. It is adaptation that enhances the ability and chances of survival. Adaptation vary among species but has the common objective i.e. adjustment to variation. For example, polar bears possess several key characteristics and trait that make them capable of adjusting with the harsh conditions of life in Antarctica.

Chapter Analysis:

This is a medium weighted chapter. All in all, 29 questions have been put forward in the question paper spanning over the last 5 years. There is a unique trend in the number of question appearing in paper from Organisms and its Population. Every alternate year, 4 question come and going by that patter, we can expect 4 question in the next year. However, we cannot judge anything practical from pattern when it comes to prestigious examinations like NEET, and hence, an apt analysis gives the result that 2-3 question can be expected in the coming year’s papers. The following bar-graph gives the year-by-year number of question coming from Organisms and its Population. The pattern which was discussed in the above paragraph can be observed, except for one.

The important topics to be covered from this chapter are:
• Organisms and its Environment
• Graphs of Population Growth

Tips and Tricks:

1. NCERT must be read properly for this chapter as it covers most of the topics briefly. Here is the link to the NCERT PDF version of the chapter:
2. The Graphs of Population Growth must be looked at least once a day so that it is fresh. There have been papers where questions were directly asked from these graphs.
3. Practice a large number of questions from this topic and leave no stones unturned to make this chapter one of your strengths.
4. Online video lectures might help the student in having a clearer understanding of the topic.

Introduction:

An ecosystem is complex set of relationships among the living resources, habitats and residents of an area. It includes animals, plants, trees, birds, fish, water, soil, micro-organisms and people. In other words, an ecosystem comprises of all the living things in a given area, whereby they interact with each other and their non-living environment (such as soil, climate, water, earth, weather, etc.). Ecosystem can be huge as it may comprise of different plants and animals, or can be in particularly harsh places of the world. Ecosystem, at the basic functional level, contains primary producers which are capable of harvesting energy via photosynthesis. Next are the consumers and these consumers can be primary consumer. Decomposers work at the bottom of food chain.

Chapter Analysis:

Ecosystem turns out to be a low weightage chapter with roughly 30 questions asked in the last 11 years. Most of the times, the number of questions asked stays less than 3. However, in the year 2015 and 2012, 6 questions were asked making it a deal breaker. In the other years, most of the time 2 questions were asked. Hence, we can estimate at least 2-3 question to come from Ecosystem
The below given bar-graph plots the number of questions asked per year over the last 10 years:

The important topics to cover from Ecosystem are:
• Energy Flow
• Pyramids of Number, Biomass, and Energy
• Nutrient Cycling (Carbon and Phosphorus)
• Ecological Succession

Tips and Tricks:

This chapter has happened to be the deal breaker in 2015 and 2012, so one must devote adequate time on this chapter and play it to his/her strength. The following points might be helpful:
1. Reading the NCERT is a must for this chapter. Here is the link to the NCERT PDF version of the chapter:
2. Biome Distribution Graph must be understood clearly along with its labelling.
3. One must be thorough with the topics such as Population Growth Curve, Population Density and related factors.
4. One must make cheat sheets for the names of components of ecosystem, definitions, formulae and units.
5. Inverted Biomass Pyramid, being a strange topic, must be covered thoroughly.
6. Practice a large number of questions from this topic and leave no stones unturned to make this chapter one of your strengths.

Introduction:

Population is any undesirable change in physical, chemical or biological characteristics of air, land, water or soil. Agents that bring about such an undesirable change are called as pollutants. In order to control environmental pollution, the Government of India has passed the Environment (Protection) Act, 1986 to protect and improve the quality of our environment. We have various sources of pollution such as Gaseous Emissions, Industrial Smoke, Domestic Sewage, Industrial Effluents, Biomagnification, Eutrophication etc. This pollution causes various important atmospheric effects such as Ozone Layer Depletion, Deforestation, Bank Erosion etc. making the future of Earth a really dark period.

Chapter Analysis:

Although the last paper had 6 question from Environmental issues and the year of 2009 had 8 questions, other years have not got many questions from this chapter. Most of the time, the question count from this chapter stayed less than 4. However, on those two occasions it proved out to be game changing. All in all, 40 question have been asked in the 11 years. So, we can expect at least 3 questions from this chapter in subsequent papers. This is a medium weightage chapter.
The following bar-graph exhibits the number of questions asked each year:

The important topics to cover from Environmental Issues are:
• Air Pollution and its Control
• Water Pollution and its Control
• Agrochemical and their effects
• Solid Waste Management
• Radioactive Waste Management
• Greenhouse Effect and Global Warming
• Ozone Depletion
• Deforestation

Tips and Tricks:

1. One should always start reading NCERT in the beginning of this chapter as it has very briefly explained each and every issue. Here is the link to the NCERT PDF version of the chapter:
2. Since this chapter has been game breaker in few NEET papers, one must give proper revision to this chapter every fortnight.
3. The past year questions must be attempted by the students so that they are acquainted with the type of question being asked in papers.
4. One must create separate Flash cards for the different types of Pollution, which shall make the revision of the topic easier.
5. One must remember the exact chemical compounds responsible for the different environmental effect.