Free NEET study materials for Aspirants

NEET BIOLOGY Unit22 ENVIRONMENTAL ISSUES ENVIRONMENTAL ISSUES Human population size has grown enormously over the last hundred years. This means increase in demand for food, water, home, electricity, roads, automobiles and numerous other commodities. These demands are exerting tremendous pressure on our natural resouces, and are also contribuiting to pollution opf air, water and soil. The need of the hour is to check the degradation and depletion of our resources and pollution without halting the process of development. Pollution is any desirable change in physical, chemical or biological characteristics of air, land , water or soil. Agebnts that brings about such an desirable 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 (air, water and soil). Pollution : "Any undesirable change in physical, chemical or biologi...

NEET BIOLOGY  Unit22 Ecosystem ECOSYSTEM cosystem can be visualized as a functional unit of nature which varies greatly in size from a small pong to a large forest or a sea. Many ecologists regarding the entire biosphere as a global ecosystem, as a composite of all local ecosystems on earth. Wise range of living organisms ar present on earth surface. All living organisms such as plants, animals and microorganisms interact among themselves and also with the surrounding physical environment and maintains a balance in nature. This forms a self sustaining or funtional unit of the living world known as Ecosystem. This sytem is too muc big so that is why it is divided into two parts: terrestial and aquatic. Forest,vgrasslands and desert are examples of terrestial ecosystems ; pond lake , wetland, river and estuary are examples of aquatic ecosystems. This chapter gives us an overview of different types of ecosystems, structural as well as functional aspects related to productivit...