AGE DISTRIBUTION AND AGE PYRAMID

 Age distribution - Every population has individual different age groups .

Then the individual of a population is divided into 3 classes

1) Pre-reproductive

2) Reproductive

3) Post-reproductive

Age pyramid - Age pyramids are the graphics representation of different age groups found in a population with Pre-reproductive group at the base reproductive ones in the middle and the Post-reproductive groups at the top.

a) Juvenile age pyramid

Juvenile age pyramid is triangular shape.

The pyramid with a brought base has high percentage of young population due to high birth rate .

Such a pyramid which has less number of reproductive and old in dividule of population called as Juvenile.

b) Stable age pyramid

Stable age pyramid is ballet shaped .

The number of Pre-reproductive and reproductive individuals are almost equal .

Post-reproductive individuals are comparatively the population size is stable.

c) Contracting age pyramid

Contracting age pyramid is urn-shaped .

An urn-shaped pyramid has a narrow base with number of young individual because of low birth rate .

The reproductive and post-reproductive are more such a population is called dying and contracting.

The number of Post-reproductive individuals is also sizeable.

FUNCTION OF ECOSYSTEM

The function of ecosystem are

a) Food chain

b) Food web

c) Energy flow

d) Trophic level or Ecological pyramid

a) Food chain - Food chain is defined as the transfer of energy and nutrients through the continuous process of  " eating  and being eaten" .

The plants and animals of an ecosystem are linked link is known as food chain.

Food chain divided into 3types 

I) Terrestrial Food Chain 

II) Grass Food Chain

III) Aquatic Food Chain

Example

b) Food web

In an ecosystem the various food chain are inter-connected with each other and it is called as food web.

In an ecosystem , normally the food chain never separate as isolated unit but are inter-connected with one another to form network of food chain called food web.

A particular organisms may not occupied the same trophic level in every food chain , it may behave as secondary , tertiary consumer.

Hence food chain are inter-connected with another through different types of organisms at different trophic level.

Food web maintain the stability of an ecosystem . More complex the food web , more stable in the ecosystem .

Example:

c)Energy flow

Sun is the ultimate source of energy.

Flow of energy takes place from the producer to the decomposed.

Thus energy flow in an ecosystem is always unidirectional .

It is based on two important laws of thermodynamics.

#) First law of thermodynamics :  It state that energy can neither be created nor be destroyed but can be converted from one form to another form.

#) Second law of thermodynamics : It state that energy can't be transferred 10% from one form to other form.

During tranfer from one form of energy to another form a part of concentrated enery is converted into degraded energy and the rest amount is lost during transfer.

Example: In our domestic electric supply electric energy in converted into light energy through illumination of electric bulb.

The total electric energy spent for illustration is not converted 10% into light energy .

Apart of it is converted into light energy and rest is lost as heat energy produced by electric bulb .

10% Rule of energy flow : 

Lindemann in 1942 proposed the 10% rules of energy flow and according to him , about 10% of energy is transferred from one trophic level to the next trophic level.

If in an ecosystem the net primary production is 100cal the secondary production at herbivores leave would be 10cal ,at primary carnivorous would be 1cal ,at secondary carnivorous would be 0.1 cal

d) Ecological pyramid

An ecological pyramid is a graphic representation of an ecological parameters , like biomass energy or number of individuals present in different trophic level of a food chain .

Ecological pyramid were first prepared by Elton in 1927 . Hence they are also called as eltonian pyramid.

In a pyramid , the various steps of a food chain are represented by the sequence . The producers are placed at the base of the pyramid and the top of the pyramid and primary carnivorous are placed between the top and base level of the pyramid.

An ecological pyramid may be upright or inverted . 

Depending upon different parameters the ecological pyramid is 3 types

#) Pyramid of number

#) Pyramid of biomass

#) Pyramid of energy 

#) Pyramid of number

It is a graphic representation of the no of individuals per unit area of various trophic level i.e. number of producer herbivores and carnivorous .

The base of the pyramid contain the number of producer where as the number of carnivorous are occupied at the top of the pyramid.

The pyramid of numbers may be upright or inverted .

In grass land ecosystem the pyramid of numbers is upright . Because the number of grass or the producer is large as compared to herbivores and carnivorous the top of the pyramid include a small or few number of carnivorous 

But in case of parasitic food chain the pyramid of number.

#) Pyramid of biomass

Biomass is the total mass of the organisms.

It is measured both as fresh and dry weight .

Pyramid of biomass is a graphic representation of biomass is present per unit area of different trophic level comparision produser at the base and top carnivorous at the top of pyramid .

Pyramid of biomass is more real than the pyramid of number .

Pyramid of biomass is upright in grass land ecosystem and inverted in the Ponds or aquatic ecosystems.

In grass land or forest maximum biomass occure in producer and it gradually decreases from the base to the top.

The herbivores and carnivorous has very low amount of biomass.

ECOSYSTEM

The term ecology was first proposed by A.G. Tansley in 1935 but the concept appearced much later . 

An ecosystem is a community of living organisms interacting with each other and their non-living environment.

What makes up an ecosystem?

• All living things (  Biotic) (plants, animals, and bacteria)

• Non living things   (Abiotic)  (the sun, rocks, and soil)

OR

An ecosystem is an ecological unit which includes both biotic and abiotic components.

Ecosystem is the interaction of both biotic and abiotic components.

In other words , Ecosystem is a self- regulated and self-sustaining structural and functional unit of nature which consists of a community of living beings and it's physical environment , both interacting and exchanging materials between them.

Ecosystem can be small and large

Ecosystem is an open system and it has no boundaries.

• Abiotic - # Sunlight

                  # Air

                  # Soil

                  # Temprature

• Biotic -   #Producer (green plants)

                  #consumer

Consumer are divided into 3 types

# Primary consumer

# Secondary consumer

# Tertiary consumer

# Primary consumer

A primary consumer is an organism that feeds on primary producers. ... Primary consumers are usually herbivores that feed on autotrophic plants, which produce their own food through photosynthesis.

# Secondary consumer

Secondary consumers are largely comprised of carnivores that feed on the primary consumers or herbivores. Other members of this group are omnivores that not only feed on primary consumers but also on producers or autotrophs. An example is a fox eating rabbit.

# Tertiary consumer

A tertiary consumer is an animal that obtains its nutrition by eating primary consumers and secondary consumers. Usually tertiary consumers are carnivorous predators, although they may also be omnivores, which are animals that feed on both meat and plant material.

EXOSPHERE

The exosphere is the uppermost region of Earth's atmosphere as it gradually fades into the vacuum of space. The air in the exosphere is extremely thin - in many ways it is almost the same as the airless void of outer space.

The exosphere has gases like hydrogen and helium, but they are very spread out. There is a lot of empty space in between. There is no air to breathe, and it's very cold.

The air in the exosphere is very thin, and is made up mostly of helium, and hydrogen. Traces of other gases such as atomic oxygen and carbon dioxide can also be found. The upper level of the exosphere is the farthest point from earth that is still affected by earth's gravity.

THERMOSPHERE

The thermosphere is a layer of Earth's atmosphere that is directly above the mesosphere and below the exosphere. It extends from about 90 km (56 miles) to between 500 and 1,000 km (311 to 621 miles) above our planet. ... Solar activity strongly influences temperature in the thermosphere.

. Radiation causes the atmosphere particles in this layer to become electrically charged particles, enabling radio waves to be refracted and thus be received beyond the horizon.

The highly attenuated gas in this layer can reach 2,500 °C (4,530 °F) during the day. Despite the high temperature, an observer or object will experience cold temperatures in the thermosphere, because the extremely low density of the gas (practically a hard vacuum) is insufficient for the molecules to conduct heat. A normal thermometer will read significantly below 0 °C (32 °F), at least at night, because the energy lost by thermal radiation would exceed the energy acquired from the atmospheric gas by direct contact. In the anacoustic zone above 160 kilometres (99 mi), the density is so low that molecular interactions are too infrequent to permit the transmission of sound.

MESOSPHERE

The mesosphere is a layer of Earth's atmosphere. The mesosphere is directly above the stratosphere and below the thermosphere. It extends from about 50 to 85 km (31 to 53 miles) above our planet. Temperature decreases with height throughout the mesosphere.

is directly above the stratosphere and below the thermosphere.

extends from around 50-85 km above our planet (31-53 miles)

possess temperatures that decrease with height throughout the mesosphere.

contains strong zonal winds (east-west), atmospheric tides, planetary waves, and gravity waves.

STRATOSPHERE

The stratosphere is a layer of Earth's atmosphere. It is the second layer of the atmosphere as you go upward. ... The bottom of the stratosphere is around 10 km (6.2 miles or about 33,000 feet) above the ground at middle latitudes. The top of the stratosphere occurs at an altitude of 50 km (31 miles).

The stratosphere is where you'll find the very important ozone layer. The ozone layer helps protect us from ultraviolet radiation (UV) from the sun. In fact, the ozone layer absorbs most of the UV radiation the sun sends to us. Life as we know it wouldn't be possible without this layer of protection.

Temperature Inversion. The lower layers of the stratosphere are colder & as we move upwards, the upper layers become hotter. ... 

Temperature Increases With Height. ... 

The Stratosphere Is Where Jets Like to Fly. 

TROPOSPHERE

The troposphere is the lowest layer of Earth's atmosphere. Most of the mass (about 75-80%) of the atmosphere is in the troposphere. Most types of clouds are found in the troposphere, and almost all weather occurs within this layer. ... Air gets colder as one rises through the troposphere.

The troposphere provides oxygen that we can breathe, keeps Earth at a livable temperature, and allows for weather to occur, making it a very important part of the atmosphere. 

HYDROSPHERES

The hydrosphere (from Greek ὕδωρ hydōr, "water"[1] and σφαῖρα sphaira, "sphere"[2]) is the combined mass of water found on, under, and above the surface of a planet, minor planet, or natural satellite. Although Earth's hydrosphere has been around for about 4 billion years,[3][4] it continues to change in shape. This is caused by seafloor spreading and continental drift, which rearranges the land and Ocean

It has been estimated that there are 1.36 billion cubic kilometers (332 million cubic miles) of water on Earth.[6] This includes water in liquid and frozen forms in groundwater, oceans, lakes and streams. Saltwater accounts for 97.5% of this amount, whereas fresh water accounts for only 2.5%. Of this fresh water, 68.9% is in the form of ice and permanent snow cover in the Arctic, the Antarctic and mountain glaciers; 30.8% is in the form of fresh groundwater; and only 0.3% of the fresh water on Earth is in easily accessible lakes, reservoirs and river systems.

The total mass of Earth's hydrosphere is about 1.4 × 1018 tonnes, which is about 0.023% of Earth's total mass. At any given time, about 20 × 1012 tonnes of this is in the form of water vapor in the Earth's atmosphere (for practical purposes, 1 cubic meter of water weighs one tonne). Approximately 71% of Earth's surface, an area of some 361 million square kilometers (139.5 million square miles), is covered by ocean. The average salinity of Earth's oceans is about 35 grams of salt per kilogram of sea water .

ATMOSPHERE

An atmosphere (from Ancient Greek ἀτμός (atmós) 'vapour, steam', and σφαῖρα (sphaîra) 'sphere') is a layer of gas or layers of gases that envelope a planet, and is held in place by the gravity of the planetary body. A planet retains an atmosphere when the gravity is great and the temperature of the atmosphere is low.[1] A stellar atmosphere is the outer region of a star, which includes the layers above the opaque photosphere; stars of low temperature might have outer atmospheres containing compound molecules. 

The atmosphere of Earth is composed of nitrogen (78%), oxygen (21%), argon (0.9%), carbon dioxide (0.04%) and trace gases.[2] Most organisms use oxygen for respiration; lightning and bacteria perform nitrogen fixation to produce ammonia that is used to make nucleotides and amino acids; plants, algae, and cyanobacteria use carbon dioxide for photosynthesis. The layered composition of the atmosphere minimises the harmful effects of sunlight, ultraviolet radiation, the solar wind, and cosmic rays to protect organisms from genetic damage. The current composition of the atmosphere of the Earth is the product of billions of years of biochemical modification of the paleoatmosphere by living organisms.

LITHOSPHERE

"Earth's lithosphere includes the crust and the uppermost mantle, which constitute the hard and rigid outer layer of the Earth. The lithosphere is subdivided into tectonic plates. ... The lithosphere is underlain by the asthenosphere which is the weaker, hotter, and deeper part of the upper mantle."

THE EARTH'S HYDROSPHERE

• The Earth's liquid water constitutes the hydrosphere.

• The vast majority of Earth's water is in the oceans (salt water), with smaller, but geologically important, quantities of fresh water in lakes, rivers, and ground water.

• the total mass of Earth's water is about 300 times the mass of the atmosphere.

• Without water, which facilitates the formation of carbonate rock, the atmospheric content of CO₂ would be far higher than it is.

NARMADA BACHAAO ANDOLAN

The most popular movement in the environmental history of india is the movement against the Narmada river valley project .

The Narmada is the largest west flowing river on the Indian peninsula.

The Narmada wind's itself 1.312 km long words to the Arabian sea through lovely forested hills rich agricultural plains and narrow Rocky gorgeous in a series of falls.

More than twenty one millions people live in the Valley , mostly in villages .

Many tribal groups .

Such as the Bhils and the gonds occupied the forested uplands.

The Narmada valley is the site of one of the world largest multipurpose water project , the Narmada river Development project which involves the construction of thirty large dams and many small ones on the river and it's fifty one main tributaries .

The project will transform the valley and lives of its residency and will increase food production and hydropower generation in Gujarat , Madhya Pradesh and Maharashtra .

The construction of dam and reservoirs will displace an estimated one million people and will submerged 3,50, 000 hectares of forest land and 2,00,000 hectares of agricultural land .

The sardar sarovar dam in Gujarat , which is facing major opposition from tribal groups that hunt and collect foregoing in the jungle canyon and from villagers who are being displaced by the inundation from the reservoir , which will submerged almost 40,000hecyares of land and 250 villagers

The movement uses various tools of protest such as satyagraha ,Jal samarpan, Rastaroko , Gaonbandn demonstration and rallies hunger strikes and blockade of project.

HABITAT

Habitat is defined as the place where an organisms lives .

The term  "HABITAT " is defined by E.P. Odum in 1971.

And also defined as the specific set of physical environment which surrounds , influence and is utilised by a species population or a community.

Or, In simple , habitat is a natural environment inhabited by a particular organisms 

Example of habitat are - Forest, Grassland, Ponds, Lakes, Desert, River, Valley, Saline soil etc .

So a habitat consists of both biotic and abiotic factors .

Habitat mainly  2types i) Microhabitats

                                         ii) Monotypic                                                             habitat

Depending upon the organisms habitat may be 3 type

a) Terrestrial Habitat  Ex- Land, desert                                                    

b) Fresh Water Habitat  Ex- Ponds, Lake , River

c) Marine Habitat   Ex- Ocean

d) Estuaries Habitat Ex- semi enclosed costalt body.

i) 

ii)

COMPONENTS OF ENVIRONMENT

COMPONENTS OF ENVIRONMENT

• Atmosphere Blanket of gases surrounding the earth.

• Hydrosphere- Various water bodies present on the earth.

Lithosphere Contains various types of soils and rocks on the earth.

Biosphere- Composed of all living organisms and their interactions with the environment.

Atmosphere

•The atmosphere forms a protective shell over the earth.

• The lowest layer, the troposphere, the only part warm enough for us to survive in, is only 12 kilometers thick.

The stratosphere is 50 kilometers thick and contains a layer of sulphates which is important for the formation of rain.

. It also contains a layer of ozone, which bsorbs ultra-violet light

HYDROSPHERE

• The hydrosphere covers three quarters of the earth's surface.

• A major part of the hydrosphere is the . marine ecosystem in the ocean, while only a small part occurs in fresh water.

Fresh water in rivers, lakes and glaciers, is perpetually being renewed by a process of evaporation and rainfall.

. Some of this fresh water lies in underground aquifers.

Human activities such as deforestation Create serious changes in the hydrosphere.

LITHOSPHERE

The crust of the earth is 6 or 7 kilometers thick and lies under the continents.

• Rocks, when broken down. form soil on which man is dependent for his agriculture. Their minerals are also the raw material used in various industries

Environmental

We can see many things around us. Some of them are living such as, the birds, animals and our friends whereas others are non-living like the tables, chairs, books, mountains and water. These living and non-living things which we see around us form our environment.

The elements in our environment help us to live on Earth. The soil helps plants to grow, air is needed for breathing and water is needed for drinking.

Are plants living or non-living?

Many of our activities harm and bring changes in the environment. The waste generated by ourdaily activities make our environment dirty and impure This has led to pullin Pollution is of four types-Air Pollution, Water Pollution, Land Pollution and No Pollution.

Air Pollution

Air gets polluted due to smoke from factories and vehicles, bursting of firecrackers and burning of garbage. It causes breathing problems like asthma and bronchitis

Water Pollution

Air pollution

Industrial waste

Garbage in the

Water pollution is caused due to the following

reasons.

1. Throwing garbage into the river.

2. Releasing industrial wastes into water bodies.

3. Bathing animals.

4. Washing clothes, utensils and people bathing in rivers.

Water pollution is very harmful. If a person drinks such polluted water, he falls sick. Diseases like typhoid, jaundice and cholera spread due to polluted water.

Washing of clothes in the river.

NARMADA BACHAAO ANDOLAN

The most popular movement in the environmental history of india is the movement against the Narmada river valley project .

The Narmada is the largest west flowing river on the Indian peninsula.

The Narmada wind's itself 1.312 km long words to the Arabian sea through lovely forested hills rich agricultural plains and narrow Rocky gorgeous in a series of falls.

More than twenty one millions people live in the Valley , mostly in villages .

Many tribal groups .

Such as the Bhils and the gonds occupied the forested uplands.

The Narmada valley is the site of one of the world largest multipurpose water project , the Narmada river Development project which involves the construction of thirty large dams and many small ones on the river and it's fifty one main tributaries .

The project will transform the valley and lives of its residency and will increase food production and hydropower generation in Gujarat , Madhya Pradesh and Maharashtra 

HARDY- WEINBERG'S PRINCIPLE

Hardy-aweinberg principles gives the geneticists a tool to determine when evolution is occurring .

Population geneticists use Hardy- Weinberg principle to calculate a starting point allele frequency and than compare it to frequency measured at some future time .

Hardy-weinberg's use the binomial expression p^2+2pq+q^2=2 to calculate the genotypic and allele frequency of a population.

cDNA LIBRARY

The copy of DNA formed on mRNA is called cDNA .

1,000- 30,000 types of various mRNA sequences can be obtained from a typical eukaryotic cell .

cDNA library and cDNA clone bank are the population of such viruses where each virus has at least one cDNA inserted plasmid is present .

In a complete viral population each member has from outside DNA sequence.

It is easy to make clone bank of those viruses which have DNA as genetic material 

Example - Influenza virus and Reovirus , etc .

Prokaryotic gene has no introns ,so cDNA is the continuous copy of mRNA while eukaryotic entrance brake the DNA molecules in small segments called exon.

BIOETHICS

Bioethics are a set of standards that may be used to regulate our activities in relation to biological works .

The major bioethical concerns are as follows:

Introduction of transgenes from one species to another violates the integrity of species .

Transfer of human genes to other animals and vice versa is against ethics.

Making of clone.

May cause risk to biodiversity .

Suffering to animals used in biotechnology will increase .

BIOWAR

The use of bioweapons originated in 5th century .

Biowar is the use of biological weapons against humans and their crops and animals 

A bioweapon is a device which carries and delivery pathological and biological agents or toxins to a target 

Recently Anthrax bacterium was sent by post after attack .

It causes anthracis

Misconceptions About Biological Weapons :

1) Technically difficult .

2) Will not be used because use is morally repugnant .

3) Rarely used no change of use of biological weapons in near future.

ENVIRONMENTAL MOVEMENT

A few important environmental that were organised in India are discussed.

1- Bishnoi Movement: 

This movement was led  by Amrita Devi in which around 363 people sacrificesd their lives for the protection of their forest .

This movement was the first of its kind to have developed the strategy of hugging or embracing the trees for their protection spontaneously .

Bishnois of Rajasthan - The first Chipko movement khejarli in1970

Bishnois of Rajasthan are known as a conservation society .

They follow the teachings of Guru Jambeshwar who poreched them to follow 29 laws .

They first Chipko movement was organised by Bishnois in 1730 AD . This story of first Chipko movement is described in following lines .

Khejari of khejadi is a village in Jodhpur district of Rajasthan India 26 k. m. South east of the city of Jodhpur .The name of the town is derived from khejari trees , which were in abundance in the Village .

In this village 363 Bishnois, led by Amrita Devi sacrifice their lives in 1730 AD while protecting green khejari trees considered sacred by the community ,by hugging then this incident is the first even of Chipko movement in the recorded history .

Amrita Devi protested against king's men attempting to cut trees as it was prohibited in Bishnoi religion .

The malevolent feudal party told her that if she wanted the trees to be spared .

She should give them money as bribe .

She refused to acknowledge this demand and told them that.

She would consider it as an act of ignominy and insults to her religious faith .

She said that she would rather give away her life to save the greens trees .

It is at that stage she spoke these words.

"Sar Santey Rukh Rahe To Bhi Sasto Jan "

Meaning of this- If a tree is saved even at the cost of one's head it's worth it

THE LARGEST BOTANICAL GARDEN OF WORLD

The largest botanical garden of the world  is ROYAL BOTANICAL GARDEN.

This botanical garden is present in England.

The botanical garden is about 300 acres near London .

That is the world biggest collection of living plants .

It is also known as Historical Rock Garden.

The botanical garden was inaugurated in 1932.

While most visitors are there for the flowers exhibits .

This ONECO world heritage site has made great contribution to the botanical garden.

It's world cross attraction including a treetops walk way