Tuesday, 15 December 2020
fundamental unit of life 9th cbse notes and video links
Golgi apparatus
First described by Golgi
It is a system of membrane bound veicles arranged parallel to each other in stacks called cisterns
Draw small figures which i showed in video
They are often connected to endoplqmisc reticulated
They pack,store,modify,dispatch various material formed in cell
To inside and outside of cell
Functions are
Storing materials
Packaging
Modifying
Dispatching
Sometimes making lysosomes
Some times convers simple sugars to complex sugars
Like glucose to starch
Lysosomes
Lysosome are membrane bound cell organlees filled with powerful digestive enzymes
These enzymes are made in rough endoplasmic reticulum
They are so powerful that they can break even complex organic matter
Lysosmes are waste disposal of cell and makes the cell clean
They engulf foreign materials,bacteria,food,worn out cells
When cell is about to die
Lysosomes burst and digest its own cell also
That why lysosoems are called suicidal bags of cell
Pls draw simple figure
Vacuoles
Vacuoles are storage sacs of cell
Animals they are small
Plants they are big
Vacuoles are filled with cell sap
Gives turgidity and rigidity shape and structure to cell
They store some important substances like
Amino acids
Sugars
Protiens
Orgqnic acids
In single cell organisms
Vacuoles help in osmo regulation
Osmoregulqtion means maintainence of water and salt levels in body
Draw figure must
First described by Golgi
It is a system of membrane bound veicles arranged parallel to each other in stacks called cisterns
Draw small figures which i showed in video
They are often connected to endoplqmisc reticulated
They pack,store,modify,dispatch various material formed in cell
To inside and outside of cell
Functions are
Storing materials
Packaging
Modifying
Dispatching
Sometimes making lysosomes
Some times convers simple sugars to complex sugars
Like glucose to starch
Video link
https://youtu.be/tF85FTqWSPg
Lysosomes
Lysosome are membrane bound cell organlees filled with powerful digestive enzymes
These enzymes are made in rough endoplasmic reticulum
They are so powerful that they can break even complex organic matter
Lysosmes are waste disposal of cell and makes the cell clean
They engulf foreign materials,bacteria,food,worn out cells
When cell is about to die
Lysosomes burst and digest its own cell also
That why lysosoems are called suicidal bags of cell
Pls draw simple figure
Vacuoles
Vacuoles are storage sacs of cell
Animals they are small
Plants they are big
Vacuoles are filled with cell sap
Gives turgidity and rigidity shape and structure to cell
They store some important substances like
Amino acids
Sugars
Protiens
Orgqnic acids
In single cell organisms
Vacuoles help in osmo regulation
Osmoregulqtion means maintainence of water and salt levels in body
Draw figure must
Mitochondria
1.mitochondriq is called power house of cell
2.because it produces energy in the foem of ATP
3.ATP is called energy currency of cell
4.ATP is adenosine tri phosphate
5.ATP id used for doing metabolic activities
6.it has 2 membranes
7.outside layer is porous
8.inner layer is folded
9.folds increases surface area of production of ATP
10.mitochondria has its own DNA and its own ribosome
11.pls draw diagram whether asked or not see in video
Plastids
1.plastids are present only in paint cell
2.palstids are of 2 types
Chromoplasts
Leucoplasts
3.chromoplqsts are colored plastics
4.lecoplasts are colorless or white plastics
5.leucoplasts stores amino acids, protiens etc
6.chloroplast is type of plastid green in color
7.green colour is due to chlorophyll pigment
8.pigment has capacity to trap sunlight
9.trapping sunlight prepare glucose by photosynthesis
10.during photosynthesis co2 is absorbed and prepares glucose which converts to carbohydrates
11.chloroplast also have its own DNA and ribosome
12.pls draw diagram whether asked or not
1.mitochondriq is called power house of cell
2.because it produces energy in the foem of ATP
3.ATP is called energy currency of cell
4.ATP is adenosine tri phosphate
5.ATP id used for doing metabolic activities
6.it has 2 membranes
7.outside layer is porous
8.inner layer is folded
9.folds increases surface area of production of ATP
10.mitochondria has its own DNA and its own ribosome
11.pls draw diagram whether asked or not see in video
Plastids
1.plastids are present only in paint cell
2.palstids are of 2 types
Chromoplasts
Leucoplasts
3.chromoplqsts are colored plastics
4.lecoplasts are colorless or white plastics
5.leucoplasts stores amino acids, protiens etc
6.chloroplast is type of plastid green in color
7.green colour is due to chlorophyll pigment
8.pigment has capacity to trap sunlight
9.trapping sunlight prepare glucose by photosynthesis
10.during photosynthesis co2 is absorbed and prepares glucose which converts to carbohydrates
11.chloroplast also have its own DNA and ribosome
12.pls draw diagram whether asked or not
Endiplasmic reticulum
1.endoplasmic reticulum is network of membrane bound sheets
2.they are round ,tubular,vehicular
3.they are having same composition as of plasma membrane
4.there are 2 types of endopqlmic rer they are rough and smooth
5.rough endoplamic reticulm is rough because ribosome are attached to it
6. As they have ribosome rer helps in making protiens
7.and these protiens goes to all parts using endo reti
8.smooth are smooth as they don't have anything attached to it
9.they help in preparation of lipids or fats
10 these lipids and proteins of rer both used in making cell membrane
11.and process is called membrane biogenesis
12.ser also often helps in detoxification in liver
13.on whole
Er functions are
Transport
Network
Frame work
Membrane biogenesis
Metabolic activities
Harmones syntheais
Enzymes synthesis
And so on
14.try to draw figures as explained in video
1.endoplasmic reticulum is network of membrane bound sheets
2.they are round ,tubular,vehicular
3.they are having same composition as of plasma membrane
4.there are 2 types of endopqlmic rer they are rough and smooth
5.rough endoplamic reticulm is rough because ribosome are attached to it
6. As they have ribosome rer helps in making protiens
7.and these protiens goes to all parts using endo reti
8.smooth are smooth as they don't have anything attached to it
9.they help in preparation of lipids or fats
10 these lipids and proteins of rer both used in making cell membrane
11.and process is called membrane biogenesis
12.ser also often helps in detoxification in liver
13.on whole
Er functions are
Transport
Network
Frame work
Membrane biogenesis
Metabolic activities
Harmones syntheais
Enzymes synthesis
And so on
14.try to draw figures as explained in video
15.video link
https://youtu.be/wCiGkP-Jfbc
Nucleus
1.nucleus has double membrane porous layer
2.inside nucleus has nucleoplasm
3.chromatin reticulum entangled network is present
4.when cell is about to divide chro.qtin changes to chromosomes
5.chromosmes have DNA in it
6.DNA has genes in it
7.genes are units of inheritance
8.genes help in transferring character from parents to offspring
9.all the metabolic activities are under control of nucleus
10.in prokaryots nuclear wall is absent
11.all contents of nucleus are freely. Floating in cell
12.the nucleus of prokarypts are called as nucleoids
13.pls draw figure to explain as I did in video
Nucleus
1.nucleus has double membrane porous layer
2.inside nucleus has nucleoplasm
3.chromatin reticulum entangled network is present
4.when cell is about to divide chro.qtin changes to chromosomes
5.chromosmes have DNA in it
6.DNA has genes in it
7.genes are units of inheritance
8.genes help in transferring character from parents to offspring
9.all the metabolic activities are under control of nucleus
10.in prokaryots nuclear wall is absent
11.all contents of nucleus are freely. Floating in cell
12.the nucleus of prokarypts are called as nucleoids
13.pls draw figure to explain as I did in video
14.video link
https://youtu.be/W5qGjsVUzPE
CELL WALL
1.plant cells only have cell wall
2.cell wall is made of cellulose
3.cellulose is complex carbohydrate which gives mechanical strength and support to plant
4.loosing water and shrinking of cell is called palsmolysis
5.gaining water and bulging is called turgidity
6.cell wall protects cell during turgidd conditions from bursting
7.so plant cell resists more than animal cell as they don't have cell wall
1.plant cells only have cell wall
2.cell wall is made of cellulose
3.cellulose is complex carbohydrate which gives mechanical strength and support to plant
4.loosing water and shrinking of cell is called palsmolysis
5.gaining water and bulging is called turgidity
6.cell wall protects cell during turgidd conditions from bursting
7.so plant cell resists more than animal cell as they don't have cell wall
Plasma membrane
1.plama membrane is selectively permeable
2.made of lipids proteins
3.endoplamic reticulum helps in synthesis of plasma membrane
4.process if it's formation is called membrane biogenesis
5.plamam membrane is common in animal and plant cells.
6.inside plasma membrane pritoplasm is present
Video link of this
https://youtu.be/YF2JPPW0lEI
Wednesday, 2 December 2020
NATURAL RESOURCES 9TH CBSE NOTES
Natural resources 9th cbse
Earth is the only planet life sustains
Because earth has some important resources
Like light ,air,water,land
All living organisms depends on air light ,water
Portion of land on earth is called lithosphere
Portion of earth where water is present is called hydrosphere
Blanket of air covering earth is called atmosphere
The 3 life sustaining zones lithosphere hydrosphere and atmosphere is called biosphere
Biosphere has so many ecosystems
Ecosystem is place where biotic and abiotic factors interact with each other
Biotic components are plants animals and microorganisms
Abiotic components are air water land light etc
AIR
Air is mixture of gases
Gases in air are major nitrogen78% then oxygen21%
Remaining all are less then 1 percent
Where as in Venus and Mars 95%co2 is present
On earth it is very less because of plants absorb co2 and prepare glucose
Even marine animals consume co2 and prepare their shells
Lofe forms have mkdifies percentages of games in air
Air is insulator
Means bad conductor of heat
So air acts as a blanket on earth and maintains earth temperature steadily
In winter we use blankets because blankets have tiny pores which trap air and acts as a insulator making us feel cozy
As outer air come come inside and inside can't go outside so heat is trapped inside blanket ans we feel warm and cozy in winter with blanket
ATMOSPHERE IN CLIMATE CONTROL
Atmosphere act as blanket and maintains globe temperature
As sun rays fall on earth most of them reflect back
Atmosphere allows some rays to go back and some do not
That is how our earth temperature is regulated
But if pollution increases. Somehow co2 level increase and may trap more heat resulting on global warming that we will study later
Best example of atmosphere controlling temperature is land and sea breeze
Sea breeze
Day time land will become hot
Hot air rises up
Air from sea moves to land
It is called sea breeze
Thats why it will be very sultry and more humidity in coastal areas
Full day they sweat
Land breeze
Water has GREATER HEATING CAPACITY
Means it takes long time for heating or cooling water
By evening wqter becomes hot
Now air on water rises up
Air from land moves towards sea
This is called land breeze
So water takes long time to heat up or become cold as it has greater heating capacity
Water cycles
We learned earlier water evaporates
And then condenses to form rain
The whole process in which water evaporates
Form water vapor
Condenses to form rain
On the ground
Returning back
Is called as water cycle
We never see sea or ocean drying up
Its because of water cycle
Rain water won't return back so easily
Some of them percolate into ground
We may bring them up using tube well or bore
Other forms springs or glaciers
Some water is used by plants and animals
In different ways all the water again return back
Wtaer when returning brings so many minerals
Which will be used up eventually by marine organisms
Or enter into animals or humans when we drink
This is how complex is biogeochemical cycle water cycle is
Pls draw diagram given on text book
Always good diagram only shows
That u understood the subject
Nitrogen cycle
Nitorgen is present 78 %in atmosphere
Nitrogen also important constituent if many essential molecules like DNA rns vitamins mainly proteins
Alkaloid urea also
Nitrugen is very important but these organisms can't use them directly
Except few bacteria none of the organisms can use them directly
These bacteria are rhizobium bacteria which live in root nodules of legumes pulses plants
Other then this bacterial remaining all organisms get their nitrogen in different ways
During lightning and thunderstorms
Nitrogen in atmosphere reacts with oxygen and forms nitrogen dioxide
They react with water and fall on ground as acid rain
N2 + O2 gives N2O3 or N2O5
N2O3 or N2O5 with water forms HNO3 or HNO2
And fall on ground as acid rain
These rae then utilized by various life forms
Plants take nitrates or nitrites and convert them into amino acids
Amino acids form proteins
When animals eat these plants or animals which eat them
That amino acids enter into their bodies
Once this animal or plant dies the amino acids in them are converted back into nitrites or nitrates
Then different types of bacteria convert it back into elemental bacteria
Thus nitrogen enters back into atmosphere
So whole process can be easily studies as
Nitorgen fixation
Done by lighting and acid rain
Or symbiotic bacteria like
Rhizobium or azatobacter
Nitrification
Ammonia is coverted to nitrites or nitrates by nitrifying bacteria
Like
Nitrosomonas ,nitrococcus
Ammonifying bacteria
After plants and and animals die
Nitrites or nitrates are converted to ammonia by ammonifying bacteria
Eg.
Bacillus bacteria
Denitrification
Denitrifyring bacteria converts ammonia to nitrogen
Pseudomonas
Bacillus
And also some fungus also does this
Carbon cycle
Carbon is constituent of all organic matter on the earth
In diamonds graphite coal coke it is found in elemental form
In co2 co carbonates bicarbonate its in compound form
All life forms are based on proteins carbohydrates fats nucleic acids and vitamins
[ ] The endoskeletom and exoskeleton of many life forms also formed from caco3
Carbon is coming mainly from plants which are taking co2 in photosynthesis
Then co2 is concerted to carbohydrates
Then glucose is used for various other metabolic activities
Then glucose is used in respiration and in respiration oxygen is liberated into atmosphere
Then oxygen is used in respiration and co2 is liberated back into atmosphere
Co2 also comes from various methods like combustion.vehicles heating etc
Green house effect
Its same like heat is trapped in glass
Suppose u put ur car in hot sunny day .once you get into car it will be very hot.
Its because glass trap.
How it traps means
Light goes inside
Looses its velocity
Cannot come out
Trapped inside
So becomes hot
In the same way it co2 level in atmosphere increases it causes green house effect
Results in global warming
Some of the gree house gases are co2 and ch4 methane
Which if increases in atmosphere
Results in trapping of sunlight such effect is called green house effect
Oxygen cycle
After. Nitrogen
Oxygen is 21 % in atmosphere
In air oxygen is also int the form of co2 and on earth in various compounds its present
Elemental oxygen from atmosphere is taken in 3 cases
Combustion
Respiration
Nitrogen oxides formation
But oxygen returns only in the form of photosynthesis
Ozone layer
Oxugen is present as o2 in the atmosphere
Oxygen combines to form ozone during lighting and thunderstorms
Even though its poisonous gas
It prevents reaching of us rays to earth
But cfc chloro flouri carbon can deplete ozone layer
So avoiding using of cfcs are taken seriously
Because if ozone depletes it make up rays reach earth
Which is very dangerous
May cause skin cancer.crops cannot go and even dangerous for every life form
Cfcs are mainly released from aerosols.rocket fuels.sparays .perfumes.jet planes
All these usage are banned with declaration of UNEP in 1986
Which proposed immediate freezing of cfs all over the world
For the sake of mankind
Earth is the only planet life sustains
Because earth has some important resources
Like light ,air,water,land
All living organisms depends on air light ,water
Portion of land on earth is called lithosphere
Portion of earth where water is present is called hydrosphere
Blanket of air covering earth is called atmosphere
The 3 life sustaining zones lithosphere hydrosphere and atmosphere is called biosphere
Biosphere has so many ecosystems
Ecosystem is place where biotic and abiotic factors interact with each other
Biotic components are plants animals and microorganisms
Abiotic components are air water land light etc
AIR
Air is mixture of gases
Gases in air are major nitrogen78% then oxygen21%
Remaining all are less then 1 percent
Where as in Venus and Mars 95%co2 is present
On earth it is very less because of plants absorb co2 and prepare glucose
Even marine animals consume co2 and prepare their shells
Lofe forms have mkdifies percentages of games in air
Air is insulator
Means bad conductor of heat
So air acts as a blanket on earth and maintains earth temperature steadily
In winter we use blankets because blankets have tiny pores which trap air and acts as a insulator making us feel cozy
As outer air come come inside and inside can't go outside so heat is trapped inside blanket ans we feel warm and cozy in winter with blanket
ATMOSPHERE IN CLIMATE CONTROL
Atmosphere act as blanket and maintains globe temperature
As sun rays fall on earth most of them reflect back
Atmosphere allows some rays to go back and some do not
That is how our earth temperature is regulated
But if pollution increases. Somehow co2 level increase and may trap more heat resulting on global warming that we will study later
Best example of atmosphere controlling temperature is land and sea breeze
Sea breeze
Day time land will become hot
Hot air rises up
Air from sea moves to land
It is called sea breeze
Thats why it will be very sultry and more humidity in coastal areas
Full day they sweat
Land breeze
Water has GREATER HEATING CAPACITY
Means it takes long time for heating or cooling water
By evening wqter becomes hot
Now air on water rises up
Air from land moves towards sea
This is called land breeze
So water takes long time to heat up or become cold as it has greater heating capacity
14.1 activity
Heat sand and water keeping in sunlight and put thermometer
After one hour nite down there temperatures
It will show that sand is more hot then water
Showing that water takes long time to get heated up
Because it has greater heating capacity
14.3 activity
See any smoke or fire
You will see it always goes up
Its because hot air blows up
As on heating
Molecules go far
It becomes lighter
Hence moves up
By conventional current
Movement of air winds
Water vapor is formed due to heating of water bodies
And also due to activities of living organisms
Atmosphere also gets heated up due to radiation of reflected rays
After heating conevctionl air is set up in the air
Always hot air moves up we saw in q4.2 activity
Similarly hot air above land and air rrises up
But land gets heated up faster then wqter
So in coastal areas morning we will see sea breeze
At night we see land breeze
Movement of air is called wind
Movement of wind occurs due to difference in heating of land by sun.
Apart from difference in heating other factors also effect movement of winds
Like
Rotation of earth
Presence of mountains
Eg of Himalayas
RAIN
14.3 activity
When air with very high content of water vapor moves from high pressure reguon to low pressure region or vivmce versa
Water gets heated during day
Lot of water gets converted to water vapor
Water vapor goes into air
Some other vapor is collected due to activities of living organisms
This air also get heated up
Hot air rises up with water vapor
As air rises it expands and cool down
On cooling water vapor becomes into droplets
This water drop will surround some dust or some other particles
Which form as nucleus like dust
Once water droplets are formed
They keep growing by condensation
When they grow heavy and big
They fall down as rain
When the temperature of air is low enough
Precipitation or snow fall may also occur
Rainfall patterns are decided by prevailing wind patterns
In India we may get rains by south west or north east monsoons
We also heard that depression in bay if Bengal
AIR POLLUTION
Fossil fuels contain small amounts of nitrogen and sulphur in them
When they are burnt there oxides enter into atmospheres
And they amy also react with rain and fall on earth as acid rain
When we inhale them also they are dangerous
Fossil fuel burning not only liberates this nitrogen and oxygen they also liberate suspended particles in air
Like carbon unburnt particles ask is formed in air
High levels of there hydrocarbons in air is very dangerous
Visibility decreases and even in cold countries fog smog may form
Accidents may also occur
Regular breathing of this polluted air may increase allergies. Cancer and skin diseases
So
Increase in harmful content in the air is called as air pollution
Increase in air pollution. In atmosphere leads to acid rains and allergies
Even carbon monoxide is also dangerous
Heat sand and water keeping in sunlight and put thermometer
After one hour nite down there temperatures
It will show that sand is more hot then water
Showing that water takes long time to get heated up
Because it has greater heating capacity
14.3 activity
See any smoke or fire
You will see it always goes up
Its because hot air blows up
As on heating
Molecules go far
It becomes lighter
Hence moves up
By conventional current
Movement of air winds
Water vapor is formed due to heating of water bodies
And also due to activities of living organisms
Atmosphere also gets heated up due to radiation of reflected rays
After heating conevctionl air is set up in the air
Always hot air moves up we saw in q4.2 activity
Similarly hot air above land and air rrises up
But land gets heated up faster then wqter
So in coastal areas morning we will see sea breeze
At night we see land breeze
Movement of air is called wind
Movement of wind occurs due to difference in heating of land by sun.
Apart from difference in heating other factors also effect movement of winds
Like
Rotation of earth
Presence of mountains
Eg of Himalayas
RAIN
14.3 activity
When air with very high content of water vapor moves from high pressure reguon to low pressure region or vivmce versa
Water gets heated during day
Lot of water gets converted to water vapor
Water vapor goes into air
Some other vapor is collected due to activities of living organisms
This air also get heated up
Hot air rises up with water vapor
As air rises it expands and cool down
On cooling water vapor becomes into droplets
This water drop will surround some dust or some other particles
Which form as nucleus like dust
Once water droplets are formed
They keep growing by condensation
When they grow heavy and big
They fall down as rain
When the temperature of air is low enough
Precipitation or snow fall may also occur
Rainfall patterns are decided by prevailing wind patterns
In India we may get rains by south west or north east monsoons
We also heard that depression in bay if Bengal
AIR POLLUTION
Fossil fuels contain small amounts of nitrogen and sulphur in them
When they are burnt there oxides enter into atmospheres
And they amy also react with rain and fall on earth as acid rain
When we inhale them also they are dangerous
Fossil fuel burning not only liberates this nitrogen and oxygen they also liberate suspended particles in air
Like carbon unburnt particles ask is formed in air
High levels of there hydrocarbons in air is very dangerous
Visibility decreases and even in cold countries fog smog may form
Accidents may also occur
Regular breathing of this polluted air may increase allergies. Cancer and skin diseases
So
Increase in harmful content in the air is called as air pollution
Increase in air pollution. In atmosphere leads to acid rains and allergies
Even carbon monoxide is also dangerous
As it enter into brain reacting with haemoglobin
Water
Water is present 78 % on land underground also present ,glaciers and even in our bodies
Even some water is in the form of water vapor in the atmosphere
Even though 78 percent is there most of the water is in ocenas and seas which is saline marine and salt water
Fresh water is only present in glaciers,underground and in rivers,lakes and ponds
Availability of fresh wqter differes from place to place
In summers we face acute shortage of water
Especially in rural areas it is rampant
All reactions in all living organisms occur in water medium only
Even transportation and blood all are main composition is wter
So to stay alive water is very important
Terrestrial organisms need fresh water to survive
Because marine water has more salt which we cannot get rid of our body
More the availability of life form more will be the biodiversity in that area
Apart from water which decides life forem
Sunlight
Temeperature
Soil conditions
All decide life
Water pollution
All the pesticides and fertilizers mix with rain water and drain into nearby ponds and lakes
Even sewage is liberated into ponds and lakes
Industrial wastes are dumped and some industries also put how stuff into water to cool it
When water is released from dams cool water water from dams fall into river which is hot at surface
All this temperature fluctuations effect the marine and aquatic life
So this type of addition may effect some life forms and benefit other and thus balance between living forms will be lost
So the contributing factors for wqter pollution is
1.adding undesirable substance effect water
Like mercury enter from paper industries
Some bacteria many cause cholera
2.execsive growth of algae may deplete levels of oxygen causing biological oxygen demand
3.temeparture changes may effect karvas and eggs of organisms
Soil
Mineral riches in the soil
Soil decides the diversity if life in that area
Soil is a part of earths crust which also supplies variety of minerals to living things
From soil only we can take minerals not from rocks
How soil is formed
By weathering of rocks
Huge rocks break and make soil over a period of time
Breaking of rocks factors involved are
Sun
Water
Wind
Living organisms
Sun
Day time rocks expand due to heat
Nights they cool down due to cold
Due to continuation expansion and contraction
Uneven surface and uneven expansion and contraction
Results in cracks in huge rocks
Which eventually breaks up into smaller peices
Water
Wqter settles in between cracks
Freezes
On freezing all substance expand
So continuos contraction and expansion results in widening of cracks
Or
Water flowing causes abrasion
Some rocks break and flow with water
They in turn cause abrasion to another rocks
Which slowly helps in formation of soil
Wind
Wind also erodes rocks
Make them move
Cause abrasion
Resulting in further breaking
Even wind takes soil from from one place to other also like water
Living organisms
Living organisms also influence formation of soil
Lichens grow on rocks
Lichen is symbiotic association of algae and fungi
They release certain chemicals
Which make rocks to break
And form thin layer of soil
Now on small peices mosses will grow
Which breaks them further
Also some time roots of trees Penetrqte into rocks
And makes them to break
Compisition of soul
Soil consists of smaller peices of rock
Bits of decayed living organisms called humus
Microscopic life
Minerals
Type of soil is decided by size of soil particles
Quality if soil is decided by
amount of humus
And
Microscopic life
Humus is major factor in deciding
Soil structure
Because
It makes soil to become more porous
Allows water
Allows air to Pentwater deep
Factors on which plants depend
Minerals depend on rocks from which it is formed
Nutrient content of soil
Amount of humus
Depth of soil
Quality of top soil decides the biodiversity of that particular area
Modern farming techniques
Have resulted in
Excessive use of fertilizers
Pesticides
Insecticides
Which are destroying quality of soil
And killing microorganisms in soil
Microorganusms only recuse nutrients in soil
Earthworms also play major role
Soil pollution is caused
By death of microorganisms
Death of earth worms
Adding undesirable substances
Not following sustainable management
Depletion of desirable substances
Soil we are seeing today is created at some other place
Resulting in soil erosion
By flowing wqter
Overgrazong
Winds
Deforestation
Urbanization
Vegetative covering is important
In deciding soil erosion
Plants bind the soil
Water is present 78 % on land underground also present ,glaciers and even in our bodies
Even some water is in the form of water vapor in the atmosphere
Even though 78 percent is there most of the water is in ocenas and seas which is saline marine and salt water
Fresh water is only present in glaciers,underground and in rivers,lakes and ponds
Availability of fresh wqter differes from place to place
In summers we face acute shortage of water
Especially in rural areas it is rampant
All reactions in all living organisms occur in water medium only
Even transportation and blood all are main composition is wter
So to stay alive water is very important
Terrestrial organisms need fresh water to survive
Because marine water has more salt which we cannot get rid of our body
More the availability of life form more will be the biodiversity in that area
Apart from water which decides life forem
Sunlight
Temeperature
Soil conditions
All decide life
Water pollution
All the pesticides and fertilizers mix with rain water and drain into nearby ponds and lakes
Even sewage is liberated into ponds and lakes
Industrial wastes are dumped and some industries also put how stuff into water to cool it
When water is released from dams cool water water from dams fall into river which is hot at surface
All this temperature fluctuations effect the marine and aquatic life
So this type of addition may effect some life forms and benefit other and thus balance between living forms will be lost
So the contributing factors for wqter pollution is
1.adding undesirable substance effect water
Like mercury enter from paper industries
Some bacteria many cause cholera
2.execsive growth of algae may deplete levels of oxygen causing biological oxygen demand
3.temeparture changes may effect karvas and eggs of organisms
Soil
Mineral riches in the soil
Soil decides the diversity if life in that area
Soil is a part of earths crust which also supplies variety of minerals to living things
From soil only we can take minerals not from rocks
How soil is formed
By weathering of rocks
Huge rocks break and make soil over a period of time
Breaking of rocks factors involved are
Sun
Water
Wind
Living organisms
Sun
Day time rocks expand due to heat
Nights they cool down due to cold
Due to continuation expansion and contraction
Uneven surface and uneven expansion and contraction
Results in cracks in huge rocks
Which eventually breaks up into smaller peices
Water
Wqter settles in between cracks
Freezes
On freezing all substance expand
So continuos contraction and expansion results in widening of cracks
Or
Water flowing causes abrasion
Some rocks break and flow with water
They in turn cause abrasion to another rocks
Which slowly helps in formation of soil
Wind
Wind also erodes rocks
Make them move
Cause abrasion
Resulting in further breaking
Even wind takes soil from from one place to other also like water
Living organisms
Living organisms also influence formation of soil
Lichens grow on rocks
Lichen is symbiotic association of algae and fungi
They release certain chemicals
Which make rocks to break
And form thin layer of soil
Now on small peices mosses will grow
Which breaks them further
Also some time roots of trees Penetrqte into rocks
And makes them to break
Compisition of soul
Soil consists of smaller peices of rock
Bits of decayed living organisms called humus
Microscopic life
Minerals
Type of soil is decided by size of soil particles
Quality if soil is decided by
amount of humus
And
Microscopic life
Humus is major factor in deciding
Soil structure
Because
It makes soil to become more porous
Allows water
Allows air to Pentwater deep
Factors on which plants depend
Minerals depend on rocks from which it is formed
Nutrient content of soil
Amount of humus
Depth of soil
Quality of top soil decides the biodiversity of that particular area
Modern farming techniques
Have resulted in
Excessive use of fertilizers
Pesticides
Insecticides
Which are destroying quality of soil
And killing microorganisms in soil
Microorganusms only recuse nutrients in soil
Earthworms also play major role
Soil pollution is caused
By death of microorganisms
Death of earth worms
Adding undesirable substances
Not following sustainable management
Depletion of desirable substances
Soil we are seeing today is created at some other place
Resulting in soil erosion
By flowing wqter
Overgrazong
Winds
Deforestation
Urbanization
Vegetative covering is important
In deciding soil erosion
Plants bind the soil
Water cycles
We learned earlier water evaporates
And then condenses to form rain
The whole process in which water evaporates
Form water vapor
Condenses to form rain
On the ground
Returning back
Is called as water cycle
We never see sea or ocean drying up
Its because of water cycle
Rain water won't return back so easily
Some of them percolate into ground
We may bring them up using tube well or bore
Other forms springs or glaciers
Some water is used by plants and animals
In different ways all the water again return back
Wtaer when returning brings so many minerals
Which will be used up eventually by marine organisms
Or enter into animals or humans when we drink
This is how complex is biogeochemical cycle water cycle is
Pls draw diagram given on text book
Always good diagram only shows
That u understood the subject
Nitrogen cycle
Nitorgen is present 78 %in atmosphere
Nitrogen also important constituent if many essential molecules like DNA rns vitamins mainly proteins
Alkaloid urea also
Nitrugen is very important but these organisms can't use them directly
Except few bacteria none of the organisms can use them directly
These bacteria are rhizobium bacteria which live in root nodules of legumes pulses plants
Other then this bacterial remaining all organisms get their nitrogen in different ways
During lightning and thunderstorms
Nitrogen in atmosphere reacts with oxygen and forms nitrogen dioxide
They react with water and fall on ground as acid rain
N2 + O2 gives N2O3 or N2O5
N2O3 or N2O5 with water forms HNO3 or HNO2
And fall on ground as acid rain
These rae then utilized by various life forms
Plants take nitrates or nitrites and convert them into amino acids
Amino acids form proteins
When animals eat these plants or animals which eat them
That amino acids enter into their bodies
Once this animal or plant dies the amino acids in them are converted back into nitrites or nitrates
Then different types of bacteria convert it back into elemental bacteria
Thus nitrogen enters back into atmosphere
So whole process can be easily studies as
Nitorgen fixation
Done by lighting and acid rain
Or symbiotic bacteria like
Rhizobium or azatobacter
Nitrification
Ammonia is coverted to nitrites or nitrates by nitrifying bacteria
Like
Nitrosomonas ,nitrococcus
Ammonifying bacteria
After plants and and animals die
Nitrites or nitrates are converted to ammonia by ammonifying bacteria
Eg.
Bacillus bacteria
Denitrification
Denitrifyring bacteria converts ammonia to nitrogen
Pseudomonas
Bacillus
And also some fungus also does this
Carbon cycle
Carbon is constituent of all organic matter on the earth
In diamonds graphite coal coke it is found in elemental form
In co2 co carbonates bicarbonate its in compound form
All life forms are based on proteins carbohydrates fats nucleic acids and vitamins
[ ] The endoskeletom and exoskeleton of many life forms also formed from caco3
Carbon is coming mainly from plants which are taking co2 in photosynthesis
Then co2 is concerted to carbohydrates
Then glucose is used for various other metabolic activities
Then glucose is used in respiration and in respiration oxygen is liberated into atmosphere
Then oxygen is used in respiration and co2 is liberated back into atmosphere
Co2 also comes from various methods like combustion.vehicles heating etc
Green house effect
Its same like heat is trapped in glass
Suppose u put ur car in hot sunny day .once you get into car it will be very hot.
Its because glass trap.
How it traps means
Light goes inside
Looses its velocity
Cannot come out
Trapped inside
So becomes hot
In the same way it co2 level in atmosphere increases it causes green house effect
Results in global warming
Some of the gree house gases are co2 and ch4 methane
Which if increases in atmosphere
Results in trapping of sunlight such effect is called green house effect
Oxygen cycle
After. Nitrogen
Oxygen is 21 % in atmosphere
In air oxygen is also int the form of co2 and on earth in various compounds its present
Elemental oxygen from atmosphere is taken in 3 cases
Combustion
Respiration
Nitrogen oxides formation
But oxygen returns only in the form of photosynthesis
Ozone layer
Oxugen is present as o2 in the atmosphere
Oxygen combines to form ozone during lighting and thunderstorms
Even though its poisonous gas
It prevents reaching of us rays to earth
But cfc chloro flouri carbon can deplete ozone layer
So avoiding using of cfcs are taken seriously
Because if ozone depletes it make up rays reach earth
Which is very dangerous
May cause skin cancer.crops cannot go and even dangerous for every life form
Cfcs are mainly released from aerosols.rocket fuels.sparays .perfumes.jet planes
All these usage are banned with declaration of UNEP in 1986
Which proposed immediate freezing of cfs all over the world
For the sake of mankind
Tuesday, 3 November 2020
our environment lessson 10th class case full notes
ENVIRONMENT
1.Ecosystem
Place where biotic and biotic components interact with each other is called ecosystem.
2.types of ecosystem
A.natural ecosystem
B.artificial ecosystem
3.natural ecosystem examples
Forests
Deserts
Mountains
Ocean
Big tree
4.artificial ecosystems---made by man
Examples
Crops feild
Aquarium
Zoo
Sanctuaries
Garden
5.food chain
Interdependence of various organisms in an ecosystem is called food chain
Examples of food chain
Grass land food chain
Grass- grasshoppeer-frog-snake-hawk
Forest food chain
Plants-deer-tiger
Aquatic food chain
Phyoplnaktons-zoopanktons-small fish-big fish
So many examples of food chains are given at the end of topics
6.levels of food chain
Producers
Herbivores
Omnivores
Carnivores
7.sun is primary energy producer in ecosystem
As whole world acquires energy directly or indirectly from sun only
8.decomposers are present at top
As they decay and decompose dead and decaying matter
Examples.bacteria and fungi
9.producers are so called
Example all plants
Because
1.they trap sunlight
2.prepare foood by photosynthesis
3.directly or indirectly all organisms depend on plants for energy
4.like example herbivore eat plants and get energy
5 others omnivores and carnivores eat herbivores and derive energy
6.so plants are called producers.
10.herbivores are called primary consumers
They directly depend on plants for energy
Other omnivores and carnivores depend on them for energy directly or indirectly
Example.deer,goat,giraffe,cow etc
11.omnivores are called secondary consumers
Omnivores eat both plants and animals
Eg.cockraoch,dog,cat etc
12.carnivores are called tertiary consumers
Ate those which eat only animals for energy directly
Eg.tiger lion,fox leapord
13.TROPIC LEVEL
The energy present at each level of food chain is called trophic level
14.food chain
is like pyramid shape always
With producers at bottom as they are more in number
And carnivores at top as they are least in number
On the whole food chain looks like pyramid
15.flow if energy in ecosystem is UNIDIRECTIONAL
Because
Energy moves from producers to carnivores
As energy is produced by producers
The energy from other food chains cannot be baught back
So flow of energy is unidirectional
16.food web
Interlinked food chains are called as food web
In ecosystem many organisms depend on many other organisms
So all organisms are interlinked in food chains
Such inter linked food chains is called food web
17.always remeber in food chain energy keeps decreasing from herbivores to carnivores at the rate of 10%
18.Ten percent law
Transfer of 10% energy at each level of food chain is called ten percent law
Means 90% organism will use for its metabolic activities
Whoever feeds that organism will only get 10% energy
Basing on this they are asking numericals also
Vvi
Example
1.if at plants level 10000j of energy is there how much will be at carnivores level
Plants 10000 j means
10%of it goes to herbivores
Herbivores 1000j
10%of it
Omnivores get 100j
10%of 100 j is 10j
Goes to
Carnivores will have 10 j
2.if 5j is at carnivores level how much energy at producer level
Carnivore 5 j means
Omnivores will have 50j
Herbivores will get 500j
Carnivores will get 5000j
3.if food chain is represented as
Grass-grasshopper-frog-snake-eagle
If at grass level 30000j is there
How much will be at eagle level
4.in the below food chain
In the given food chain, suppose the amount of energy at fourth trophic level is 5 kJ, what will be the energy available at the producer level?
Grass → Grasshopper → Frog → Snake → Hawk
5.if 2 j is available at carnivore level how much available at producer level
6.if 12345 j energy available at producer level how much energy available at carnivores level
19.bilogical magnification
Accumulation of harmful substance in food chain is called bio magnification.
In food chain
if any pollutant enters it keeps on accumulating in food chain
And
at producers levels it will be least and at carnivores level it will be highest
Because producers are many in number
Whereas
Carnivores are less in number
20.on the whole
Energy in food chain decreases
And
Pollutants level in food chain increases
21.ozone layer
Ozone layer main function is to obstruct
Ultra violet Ray's
Reaching earth
Sundays have various components of Ray's
Among them UV Ray's are very dangerous
If they reach earth
They can cause
Skin allergies
Cancers
Plants growth stops
So many other effects
But ozone layer getting depleted by
CFC s
Cfc means
Chloro flouro carbons
They can destroy and deplete ozone layer
Cfcs are liberated by
Aerosols
Rocket and jet engines
Refrgirants
Sprays
In 1986
UNEP
Conference
They came to conclusion that
CFC s should be freezed all over the world
After stopping usage of cfcs ozone layer formation took place
And now it is at convenient levels
UNEP
Means
United nations organisation
Ozone layer is formed
When oxygen molecule splits into oxygen atoms
Each oxygen atoms again combining with oxygen molecule
O2------- O + O
O + O2 --------- O3
22.methods of disposal of wastes
A.recyling and reuse
B.landfills
C.burning if wastes
23.Decomposers
Organisms which decay and decompose dead and decaying matter are called decomposers
Examples
Bacteria and fungi
They occupy highest position in food chain
They decay dead matter
If dead and decaying matter accumulates
They decay and liberate
Poisonous gases
Which are very toxic and dangerous
So decomposers
Cleans the environment
Environment lesson only definitions
1.ecosysstem
Place where biotic and biotic factors interact with each other
2 food chain
Interdependabmnce if various organism with each other in ecosystem
3.food web
Interlinked food chains are called food web
5.trophic level
Energy present at each level of food chain is called trophic level
6.ten percent law
Transfer of 10% of energy at each level of food chain is called ten percent law
7.biomagnification or bioaccumulation
Accumulation of harmful substances in food chain is called bio magnification
8.decomposers
Organisms which decay and decompose dead and decaying organisms are called decomposers
9.producers
Plants are called producers as they produce energy by photosynthesis to entire ecosystem
1.Ecosystem
Place where biotic and biotic components interact with each other is called ecosystem.
2.types of ecosystem
A.natural ecosystem
B.artificial ecosystem
3.natural ecosystem examples
Forests
Deserts
Mountains
Ocean
Big tree
4.artificial ecosystems---made by man
Examples
Crops feild
Aquarium
Zoo
Sanctuaries
Garden
5.food chain
Interdependence of various organisms in an ecosystem is called food chain
Examples of food chain
Grass land food chain
Grass- grasshoppeer-frog-snake-hawk
Forest food chain
Plants-deer-tiger
Aquatic food chain
Phyoplnaktons-zoopanktons-small fish-big fish
So many examples of food chains are given at the end of topics
6.levels of food chain
Producers
Herbivores
Omnivores
Carnivores
7.sun is primary energy producer in ecosystem
As whole world acquires energy directly or indirectly from sun only
8.decomposers are present at top
As they decay and decompose dead and decaying matter
Examples.bacteria and fungi
9.producers are so called
Example all plants
Because
1.they trap sunlight
2.prepare foood by photosynthesis
3.directly or indirectly all organisms depend on plants for energy
4.like example herbivore eat plants and get energy
5 others omnivores and carnivores eat herbivores and derive energy
6.so plants are called producers.
10.herbivores are called primary consumers
They directly depend on plants for energy
Other omnivores and carnivores depend on them for energy directly or indirectly
Example.deer,goat,giraffe,cow etc
11.omnivores are called secondary consumers
Omnivores eat both plants and animals
Eg.cockraoch,dog,cat etc
12.carnivores are called tertiary consumers
Ate those which eat only animals for energy directly
Eg.tiger lion,fox leapord
13.TROPIC LEVEL
The energy present at each level of food chain is called trophic level
14.food chain
is like pyramid shape always
With producers at bottom as they are more in number
And carnivores at top as they are least in number
On the whole food chain looks like pyramid
15.flow if energy in ecosystem is UNIDIRECTIONAL
Because
Energy moves from producers to carnivores
As energy is produced by producers
The energy from other food chains cannot be baught back
So flow of energy is unidirectional
16.food web
Interlinked food chains are called as food web
In ecosystem many organisms depend on many other organisms
So all organisms are interlinked in food chains
Such inter linked food chains is called food web
17.always remeber in food chain energy keeps decreasing from herbivores to carnivores at the rate of 10%
18.Ten percent law
Transfer of 10% energy at each level of food chain is called ten percent law
Means 90% organism will use for its metabolic activities
Whoever feeds that organism will only get 10% energy
Basing on this they are asking numericals also
Vvi
Example
1.if at plants level 10000j of energy is there how much will be at carnivores level
Plants 10000 j means
10%of it goes to herbivores
Herbivores 1000j
10%of it
Omnivores get 100j
10%of 100 j is 10j
Goes to
Carnivores will have 10 j
2.if 5j is at carnivores level how much energy at producer level
Carnivore 5 j means
Omnivores will have 50j
Herbivores will get 500j
Carnivores will get 5000j
3.if food chain is represented as
Grass-grasshopper-frog-snake-eagle
If at grass level 30000j is there
How much will be at eagle level
4.in the below food chain
In the given food chain, suppose the amount of energy at fourth trophic level is 5 kJ, what will be the energy available at the producer level?
Grass → Grasshopper → Frog → Snake → Hawk
5.if 2 j is available at carnivore level how much available at producer level
6.if 12345 j energy available at producer level how much energy available at carnivores level
19.bilogical magnification
Accumulation of harmful substance in food chain is called bio magnification.
In food chain
if any pollutant enters it keeps on accumulating in food chain
And
at producers levels it will be least and at carnivores level it will be highest
Because producers are many in number
Whereas
Carnivores are less in number
20.on the whole
Energy in food chain decreases
And
Pollutants level in food chain increases
21.ozone layer
Ozone layer main function is to obstruct
Ultra violet Ray's
Reaching earth
Sundays have various components of Ray's
Among them UV Ray's are very dangerous
If they reach earth
They can cause
Skin allergies
Cancers
Plants growth stops
So many other effects
But ozone layer getting depleted by
CFC s
Cfc means
Chloro flouro carbons
They can destroy and deplete ozone layer
Cfcs are liberated by
Aerosols
Rocket and jet engines
Refrgirants
Sprays
In 1986
UNEP
Conference
They came to conclusion that
CFC s should be freezed all over the world
After stopping usage of cfcs ozone layer formation took place
And now it is at convenient levels
UNEP
Means
United nations organisation
Ozone layer is formed
When oxygen molecule splits into oxygen atoms
Each oxygen atoms again combining with oxygen molecule
O2------- O + O
O + O2 --------- O3
22.methods of disposal of wastes
A.recyling and reuse
B.landfills
C.burning if wastes
23.Decomposers
Organisms which decay and decompose dead and decaying matter are called decomposers
Examples
Bacteria and fungi
They occupy highest position in food chain
They decay dead matter
If dead and decaying matter accumulates
They decay and liberate
Poisonous gases
Which are very toxic and dangerous
So decomposers
Cleans the environment
Environment definitions
Environment lesson only definitions
1.ecosysstem
Place where biotic and biotic factors interact with each other
2 food chain
Interdependabmnce if various organism with each other in ecosystem
3.food web
Interlinked food chains are called food web
5.trophic level
Energy present at each level of food chain is called trophic level
6.ten percent law
Transfer of 10% of energy at each level of food chain is called ten percent law
7.biomagnification or bioaccumulation
Accumulation of harmful substances in food chain is called bio magnification
8.decomposers
Organisms which decay and decompose dead and decaying organisms are called decomposers
9.producers
Plants are called producers as they produce energy by photosynthesis to entire ecosystem
10.herbivores
Organisms which fees only on plants
Eg .cow,goat,deer,elephant
11.omnivores
Orgnaisms which feed both on plants and animals are called omnivore
Eg.humans,cockraoch
Monday, 5 October 2020
is matter around us pure 9th cbse notes by aiimiit
Matter:
Anything that occupies space and has mass is called matter.
It exists in the form of five basic elements, the Panch tatva – air, earth, fire , sky and water.
For example: Chair, bed, river, mountain, dog, tree, building, et
Matter
Anything which has mass and occupies space is called matter. It may be solid, liquid or gas.
Types of Matter
It is of two types :
1. Pure Substance
2. Impure substance
1. Pure Substance: It may be defined as a material which contains only one kind of atoms or molecules.
Pure substances are again of two types
(a) Elements (b) Compounds
(a) Elements:
Pure substances which are made up of only one kind of atoms are known as elements.
They cannot be split up into two or more simpler substances by any of the usual chemical methods.
For example, Iron, gold, silver, carbon, oxygen, nitrogen and sodium etc.
CBSE Class 9 Science, Is Matter Around Us Pure: Important Topics and Questions
Elements are further grouped into the following three categories:
(i) Metals, for example: Iron, copper, gold, sodium, silver, mercury, etc.
(ii) Non – metals, for example: Carbon, oxygen, sulphur, nitrogen, oxygen, hydrogen, etc.
(iii) Metalloids : Boron, silicon, germanium, etc.
Properties of Metals:
These are lustrous (shine).
They conduct heat and electricity.
All metals are malleable and ductile.
They are sonorous.
All metals are hard except sodium and potassium.
All metals are solids at room temperature except mercury which is a liquid.
Properties of Non-metals:
These are dull in appearance.
They are poor conductors of heat and electricity except diamond which is a good conductor of heat and graphite which is a good conductor of electricity.
They are neither malleable nor ductile.
They are generally soft except diamond which is the hardest natural substance known.
They may be solids, liquids or gases at room temperature.
Metalloids: The elements that have properties intermediate between those of metals and non-metals, are called metalloids.
(b) Compounds:
It is a form of matter formed by combining two or more elements in a definite ratio by mass.
It Can be decomposed into its constituent elements by suitable chemical methods
For example: Water (H2O), oxygen (O2), Nitrogen dioxide (NO2), etc.
2. Impure Substance: It may be defined as a material which contains only one kind of atoms or molecules.
It is also named as mixture.
Mixtures:
A mixture is a material which contains two or more different kinds of particles (atoms or molecules) which do not react chemically but are physically mixed together in any proportion.
Types of mixture
It is of two types:
(a) Homogeneous mixture (b) Heterogeneous mixture
S. No.
Differences between home and hetero
Homogeneous mixture
Heterogeneous mixture
1.
All the components of the mixture are uniformly mixed.
All the components of the mixture are not thoroughly mixed.
2.
No separation boundaries are visible.
Separation boundaries are visible.
3.
It consists of a single phase.
It consists of two or more phases.
4.
Example: Sugar dissolved in water
Example: Air, sand and common salt.
Difference between mixtures and compounds:
S. No.Differences between mixtures and compounds
Mixtures
Compounds
1.
Various elements just mix together to form a mixture and no new compound is formed.
Elements react to form new compounds.
2.
A mixture has a variable composition.
The compound has a fixed composition.
3.
A mixture shows the properties of its constituents.
Properties of a compound are totally different from those of its constituents.
4.
They do not have a fixed melting point, boiling point, etc.
They have a fixed melting point, boiling point, etc.
5.
The constituents can be seperated easily by physical methods
The constituents can be separated only by chemical processes.
Solution:
A solution is a homogeneous mixture of two or more substances. For example: Lemon water, sugar solution, soda water, etc.
Components of Solution:
(1) Solvent: The component of the solution that dissolves the
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