The Environment and Its Components: Chapter 1 Quiz

Environmental Science

• Environmental Science is a branch of environmental studies that deals with the scientific study of environmental components, inherent or induced changes on organisms, and environmental hazards occurring due to human interactions with the environment.

The Environment

• The environment comes from the French word "environs", meaning "surroundings".
• It is defined as the sum of all external conditions affecting the life, developments, and survival of an organism.
• The environment includes everything, living or non-living, that surrounds us.

Environmental Components

• Physical Conditions (Physical Environment): non-living attributes like air, water, soil, climate, heat, light, noise, housing, radiations, and debris.
• Biological Factors (Biological Environment): include all types of flora, fauna, and micro-organisms.

The Biosphere

• The biosphere is a capsule encircling the earth's surface where all living things exist.
• It extends from 10,000 m below sea level to 6,000 m above sea level.
• Life forms do not exist outside this zone.
• The biosphere covers parts of the lithosphere, hydrosphere, and atmosphere.

The Lithosphere

• The lithosphere is the earth's crust, consisting of soil and rocks.
• The earth is an oblate spheroid, composed of the crust, mantle, and core.
• The core is around 7,000 kilometers in diameter, situated at the earth's center.
• The mantle surrounds the core, with a thickness of 2,900 kilometers.
• The crust floats on top of the mantle, composed of basalt-rich oceanic crust and granitic-rich continental crust.
• Soil is made up of inorganic and organic matter, water, and mineral constituents like oxides, silicates, and carbonates.
• Organic constituents, although forming only 4% to 6% of the lithosphere, are responsible for soil fertility and productivity.

The Hydrosphere

• The hydrosphere comprises all water resources, including surface and ground water.
• 71% of the planet's surface is covered with water.
• The hydrosphere is a vital part of the earth's life support module, providing water, air purification, temperature moderation, and waste assimilation.
• Water's excellent solvent nature is crucial for sustaining life.
• The world's water is found in oceans and seas, lakes and reservoirs, rivers and streams, glaciers and snowcaps, and ground water.
• Oceans and seas account for 96-97% of the world's water, while glaciers and polar icecaps account for 2-3%, and freshwater accounts for 5%.