NCERT CLASS 7 CHAPTER 1 YOUTUBE LINK: https://youtu.be/peW52k9hDNI

1. OUR ENVIRONMENT
Class 7
NCERT
Chapter-1

2. ENVIRONMENT
Comes from French word-
‘ENVIRONER’ meaning ‘to
surround’
Refers to all external conditions in which
An Organism lives

3. TYPES
(Classification of geographical
elements)
Natural environment
(created by nature)
Man-made environment
(man- made elements)
Eg: Mountains, rivers,
Vegetation etc.
Eg: agriculture, industries,
Settlements, means of transport etc.

4. Reasons of environmental
modifications-
 Modified by various natural and human activities
 Changes in climatic conditions in various seasons
 Everyday some species become extinct and some new evolve
 Evolution of humans was due to changes in environment
 Any change in natural environment causes variations in human environment and
vice versa

5. Natural Environment

6. Ecosystem
• Complex system of interactions between organisms and their physical
environment in a particular area.
• Most of the ecosystems are complex and contains thousands of interacting
species.
• The size of ecosystem varies greatly; it can be a s large as the rainforests,
grasslands, deserts, lakes or a s small as a pond.

7. Environmental Pollution
 An unfavorable alteration of surroundings wholly or largely.
 Result of unplanned and unwise use of technology
 Reasons-
• technological and scientific development
• overpopulation, urbanization and industrialization