PRESENTED BY ZISHAN.S.SHAIKH

GRADE 10

INTRODUCTION OF CYCLES OF LIFE

CARBON CYCLE (include video)

NITROGEN CYCLE (include video)

QUESTION AND ANSWER SESION

THE FINISHING PAGE

THE MOVEMENT OF THE MOVEMENT OF

ELEMENTS ELEMENTS

FROM ONE BODY FROM ONE BODY

TO THE OTHER.TO THE OTHER.

DEFINATION : It is a natural system consisting of plants, animals and microrganisms in an area functioning together will all non-living physical (A biotic) factors of the environment.

Earth is a biosphere with a closed system

For a steady supply of nutrient elements they must be recycled.

Different chemical elements like carbon, oxygen and nitrogen exist on earth in a fixed ratio.

NITROGEN – 78.1%NITROGEN – 78.1%

OXYGEN - 20.9%OXYGEN - 20.9%

ARGON – 0.96%ARGON – 0.96%

OTHER GASES – 0.04% OTHER GASES – 0.04%

NITROGENOXYGENARGONOTHERS

The cycle that includes both the living The cycle that includes both the living

biosphere and the non – living biosphere and the non – living lithosphere, lithosphere,

atmosphere and hydrosphere.atmosphere and hydrosphere.

The carbon cycle and the nitrogen cycle The carbon cycle and the nitrogen cycle are are

both biogeochemical cycles.both biogeochemical cycles.

THE CARBON CYCLETHE CARBON CYCLE

Carbon is a non-metal.Carbon is a non-metal.

It belongs to the group 14 elements in the It belongs to the group 14 elements in the periodic table.periodic table.

The earth’s atmosphere is 0.19% carbon.The earth’s atmosphere is 0.19% carbon.

The human body contains 18% carbon The human body contains 18% carbon that is almost that is almost hundred times more hundred times more than in the atmosphere. than in the atmosphere.

Every organism needs carbon either for its Every organism needs carbon either for its structure structure or for energy.or for energy.

The carbon cycle is a process in which The carbon cycle is a process in which carbon is recycled over and over again.carbon is recycled over and over again.

The process of recycling goes on in The process of recycling goes on in the earth’s atmosphere between the the earth’s atmosphere between the biotic and a-biotic environment.biotic and a-biotic environment.

The complete cycle is made up of The complete cycle is made up of “sources” that put back carbon into the “sources” that put back carbon into the environment and “sinks” that absorb environment and “sinks” that absorb and stores carbon. and stores carbon.

As carbon Di-oxide in the atmosphere and As carbon Di-oxide in the atmosphere and dissolves in water forming hydro carbon. dissolves in water forming hydro carbon.

Carbonate rocks in limestone and corals Carbonate rocks in limestone and corals in the form of calcium carbonate.in the form of calcium carbonate.

In sinks as coal petroleum and natural gas In sinks as coal petroleum and natural gas

Dead organic matter, e.g. humus in the Dead organic matter, e.g. humus in the soilsoil

Carbon in the form of carbon di oxide Carbon in the form of carbon di oxide enters in the phototrophic plants and enters in the phototrophic plants and algae that use it for photosynthesis. algae that use it for photosynthesis.

Carbon passes up the food chain Carbon passes up the food chain through the primary consumers.through the primary consumers.

The primary consumers metabolise in The primary consumers metabolise in presence of oxygen to produce carbon presence of oxygen to produce carbon di oxide.di oxide.

Carbon di oxide is slightly soluble and diffuses in water, for Carbon di oxide is slightly soluble and diffuses in water, for example: example: oceans and lakes. oceans and lakes.

The phytoplankton's and algae use carbon di oxide and The phytoplankton's and algae use carbon di oxide and photosynthesis photosynthesis and later become a food for the primary consumers. and later become a food for the primary consumers.

Some organisms like corals and animals with shells use carbon Some organisms like corals and animals with shells use carbon di oxide and convert it into calcium carbonate.di oxide and convert it into calcium carbonate.

Decomposition: bacteria act upon dead and decaying matter to Decomposition: bacteria act upon dead and decaying matter to form carbon di oxide.form carbon di oxide.

Over a period of time the shell sediments and the dead plants Over a period of time the shell sediments and the dead plants and animals form limestone sinks.and animals form limestone sinks.

Weathering and volcanic eruptions also add carbon di oxide to Weathering and volcanic eruptions also add carbon di oxide to the environmentthe environment

carbon di oxide is an important green house gas.carbon di oxide is an important green house gas.

excessive burning of fossil fuels release a excessive burning of fossil fuels release a considerably considerably high amounts of energy and carbon di oxide.high amounts of energy and carbon di oxide.

deforestation has reduced the amount of carbon deforestation has reduced the amount of carbon di oxide used by plants for photosynthesis.di oxide used by plants for photosynthesis.

resulting in glacial retreat and increase inresulting in glacial retreat and increase in global temperatures.global temperatures.

the sea levels have also increased due to the sea levels have also increased due to human interference.human interference.

Nitrogen is a non – metal element usually in Nitrogen is a non – metal element usually in gaseous state.gaseous state.

It belongs to group 15 and period 2 of the It belongs to group 15 and period 2 of the periodic table. periodic table.

It is the most abundant element in the earth’s It is the most abundant element in the earth’s atmosphere, it makes up 78% of the atmosphere.atmosphere, it makes up 78% of the atmosphere.

The human body consists 3% nitrogen.The human body consists 3% nitrogen.

Nitrogen is the building block of amino acids, Nitrogen is the building block of amino acids, which which form the proteins, enzymes and form the proteins, enzymes and nucleic acids.nucleic acids.

The transfer of nitrogen and nitrogenThe transfer of nitrogen and nitrogen

containing compounds in the containing compounds in the

biotic and A biotic environment.biotic and A biotic environment.

Plants and animals can’t use atmospheric nitrogen.Plants and animals can’t use atmospheric nitrogen.

Nitrogen fixation: conversion of atmospheric Nitrogen fixation: conversion of atmospheric nitrogennitrogen into nitrites and nitrates.into nitrites and nitrates.

Either by lightning or through some bacteria and Either by lightning or through some bacteria and algae algae present in the soil.present in the soil.

These nitrogenous compound enter the food cycle These nitrogenous compound enter the food cycle through the plants.through the plants.

The excretory product and the dead are then The excretory product and the dead are then converted by de-nitrification to ammonia gas. converted by de-nitrification to ammonia gas.

The major human activity involves excessive The major human activity involves excessive

fossil fuel combustion.fossil fuel combustion.

The production and use of fertilizers.The production and use of fertilizers.

Resulting in global climate change, stratospheric Resulting in global climate change, stratospheric

ozone depletion, regional smog, visibility ozone depletion, regional smog, visibility degradation acid degradation acid

rain, water – use impairment and eutrophication.rain, water – use impairment and eutrophication.

Acid rain is rain or any other form of Acid rain is rain or any other form of

precipitation which is usually acidic.precipitation which is usually acidic.

The term “acid rain” is commonly The term “acid rain” is commonly used to used to

mean deposition of acid components in mean deposition of acid components in rain, rain,

snow, fog, dew or dry particles.snow, fog, dew or dry particles.

Compounds like sulphur dioxide Compounds like sulphur dioxide and nitrogen oxides are released.and nitrogen oxides are released.

Oxides reacts with water to form Oxides reacts with water to form acid acid

precipitation called acid rain. precipitation called acid rain.

CONTROL DEFORESTATION TREAT CHEMICAL

WASTE BEFOREDISPOSAL

USE BIO-DEGRADABLE PRODUCTS RECYCLE THE WASTE

USE VEHICLE WHEN NECESSARY