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Success is how high you bounce when you hit bottom
10:08

10 Differences between Pioneer Community and Climax Community


Pioneer community vs Climax community
Ecological succession is the gradual replacement of one community with another till reaching a final stable climax community over a period of time
The first set of species or community that develops in a bare area in ecological succession is the pioneer community.
Pioneer species facilitate succession.
The final steady stable self sustaining community in an ecological succession is called the climax community. Climax community is in equilibrium with physical environment also as long as the environment remains unchanged
10 Differences between Pioneer Community and Climax Community
Pioneer community
Climax community
It is the first community that appears in a bare area during ecological succession (primary community)
It is the final stable biotic community that appears in an area during ecological succession (final community)
The establishment of the pioneer community is the first step in ecological succession (first seral stage)
The emergence of the stable climax community is the final step in ecological succession (last seral stage)
Pioneer community appears on a previously uninhabited area
Climax community establishes in a previously occupied area by other seral communities
Pioneer community consists of generally small sized species
Climax community consists of species of different sizes that are well adapted to the environment
The species in the community are tolerant to extreme environments
The species in the climax community are comparatively less tolerant to extreme environments
*Pioneer species are generally ‘r-selected’ species that are fast growing, shade intolerant and short lived
Climax species are k selected species that are slow growing, shade tolerant and long lived
Pioneer species are good colonizers but poor competitors
Climax species are poor colonizers but good competitors
Pioneer species are generally with numerous small seeds capable of dormancy, well dispersed by animals or wind, low density, pale, non-durable timber
Climax species are generally with few larger seeds capable of dormancy, well dispersed by animals or wind, low density, pale, non-durable timber
Responsible for soil formation and modifies the environment favoring the colonization of other species of next seral stage
The environment has been modified and made suitable for the emergence of species of climax community by the species of previous seral stages
Pioneer community is replaced by the species of next seral communities
Climax community is a stable community where invasion of other species will not generally happen for a long period
Examples of pioneer species: Lichen in lithosere (rocks),
Pioneer community: Phytoplanktons in hydrosere
Examples: Climax species: White spruce (Picea glauca) climax species in the Northern forests of North America.
Giant sequoia tree in sequoia forests
Climax community: forest
*Exceptions: Lichens are pioneer species on rocks, but slow growing
Reference
1. Guariguata, M. R., & Ostertag, R. (2001). Neotropical secondary forest succession: changes in structural and functional characteristics. Forest ecology and management, 148(1-3), 185-206.
2. Tobin, A. J., & Dusheck, J. (2005). Asking about life. Cengage Learning.
09:49

5 Differences between Nitrogen fixation and Nitrification


Nitrogen cycle is a continuous series of natural processes by which nitrogen passes successively from air to soil to organisms and back to air or soil involving principally nitrogen fixation, nitrification, decay, and denitrification.

The major processes in nitrogen fixation are
1. Nitrogen fixation: Conversion of atmospheric nitrogen to ammonia (NH3) in soil
N2 + 8 H+ + 8 e+ 16 ATP → 2 NH3 + H2 +16 ADP +16 Pi
2. Nitrification: biological oxidation of ammonia (NH3) to nitrite (NO2-) and then to nitrate (NO3-)
3. Nitrate assimilation: Soil nitrate (NO3-) used by plants for synthesis of N containing biomolecules like proteins, nucleic acids
4. Ammonification: Formation of ammonia (NH3) from N containing biomolecules of dead organisms
5. Denitrification and Anammox. : Reversal of nitrification where nitrate (NO3-) is converted to N2 and released to atmosphere
Refer this post for simple step wise explanation: 5 steps in N2 cycle with notes on Anammox
5 Differences between Nitrogen fixation and Nitrification
Nitrogen fixation
Nitrification
Nitrogen fixation is the conversion of nitrogen (N2) to ammonia (NH3) or compounds that can be readily utilized by plants for the synthesis of nitrogen containing bio-molecules like amino acids, nucleic acids etc 

It is a two step process that converts ammonia (NH3) to nitrate (NO3-)

Nitrogen fixation is the first step in nitrogen cycle that fix atmospheric nitrogen to soil as ammonia (NH3)
Nitrification is a major step in the nitrogen cycle in soil where soil ammonia (NH3) is converted to soil nitrate (NO3-)
Nitrogen fixation occurs by a) biological Nitrogen Fixation, b) non-biological N2 fixation by lightning, volcanic eruptions etc and c) Industrial N2 fixation called Haber-Bosch process. More than 70% of Nitrogen is fixed by biological methods
Nitrification is the biological oxidation of ammonia (NH3) to nitrite (NO2-) and then to nitrate (NO3-) by nitrifying bacteria
The microorganisms involved in Nitrogen fixation are called nitrogen fixers or diazotrophs
The microorganisms involved in Nitrification are called nitrifying bacteria
Nitrogen fixers are either symbiotic or free living.
Nitrogen fixers include some bacteria like Rhizobium in symbiotic association with leguminous plants, blue green algae like Anabaena and lichens like Collema.
Nitrification is carried out by two groups of bacteria; nitrite bacteria like Nitrosomonas which converts ammonia (NH3) to nitrite (NO2-) and nitrate bacteria like Nitrobacter that converts nitrite (NO2-) to nitrate (NO3-)
02:28

Difference between Renewable resources and Nonrenewable resources (Renewable vs Nonrenewable resources)

Exhaustible resources are of two types: Renewable and nonrenewable.
Renewable resources: They are exhaustible natural resources which get replenished, recycled or reproduced and can last forever provided they are not used beyond their renewability. it include biotic and abiotic resources. 
Nonrenewable resources: They are exhaustible natural resources which can not be gained or reconstructed once they have been used up due to lack of recycling or regeneration. 
Renewable vs Nonrenewable resources
Renewable resources:
  1. They are  exhaustible resources which get regenerated or recycled
  2. Renewable resources can last forever if used judiciously
  3. Availability can be increased by enhancing their renewability without causing depletion.
  4. They include edaphic resource (soil or land), water resources and biological resources or bioresouces (living organisms and their products-agriculture, aquaculture, poultry, livestock etc),soil  fertility, forests, underground water etc

Nonrenewable resources:
  1. Nonrenewable resources are exhaustible resources  which do not get regenerated or recycled
  2. They are going to get exhausted sooner or later whether or not used judiciously
  3. Availability can be increased only by increasing their extraction but it will cause early depletion.
  4. Fossil fuels (coal, lignite, petroleum), Mineral deposits, metals, natural gas are examples.
02:02

Difference between Inexhaustible and Exhaustible Resources


Resources are the sources of supply or support, generally held in reserve”.It include useful information, valuable services and essential materials. Resources are of two main groups:
 1)Human resources: wisdom, knowledge, experience, expertise, labour
 2)Natural resources: natural occurring resources of the biosphere, which can support and sustain life.
The natural resources are classified in different ways.
i) Based on origin, natural resources are classified into abiotic and biotic resources.

    a) Abiotic resources: Not obtained from or produced by living organisms.
         example of abiotic resources: Land, water, air
    b) Biotic (organic) resources
         example of biotic resources: Living organisms and their products
Difference between Inexhaustible and Exhaustible Resources
ii) Based on the abundance, availability, recycling and regeneration, natural resources are classified into Inexhaustible and exhaustible resources
 a) Inexhaustible (Non depletable)
  1. The resources have no change of getting depleted or exhausted
  2. The resources are present in unlimited or infinite quantities
  3. Excessive and improper use may result in their pollution .
  4. Example of Inexhaustible resources: Solar energy, (cosmic resources) wind power, hydro power, rain fall (climatic resources)
b) Exhaustible (Depletable):
  1. The resources have every chance of getting depleted or exhausted. 
  2. The resources have finite supply
  3. Excessive and improper use may result in wastage and depletion of the resources.
  4. Example of Exhaustible resources: Forests, grassland, fossil fuels, minerals,

It may be of two types: 
b (i)Renewable resources (Edaphic resources, water resources, bioresouces)
 b (ii) Non renewable resources(Fossil fuels, Mineral deposits, Biological resources)
Read more: Difference between Renewable and Non renewable Resources 
09:43

5 Differences between Energy Flow and Nutrient Cycling


Ecosystem is the structural and functional unit of nature. It is a stable life supporting system that involves extensive interactions between biotic and abiotic components. The two most fundamental processes in any ecosystem are the flow of energy and the cycling of nutrients.
Definition of Energy flow: The transfer of energy from one trophic level to another in a non-cyclic and linear manner through food chain and food web is called energy flow. Each step in the food chain is called trophic level.

Nutrient cycling is the cyclic back and forth movement of chemical elements between organisms and their physical environment of an ecosystem. It generally starts from nutrient pool (air, soil) to producers, producers to consumers, consumers to decomposers and then back to nutrient pool.
Differences between Energy Flow vs Nutrient Cycling
Energy Flow
Nutrient Cycling
The transfer of energy from one trophic level to another in a non-cyclic and linear manner through food chain and food web is called energy flow
It is the cyclic  movement of nutrients between living organisms and their physical environment in an ecosystem
The flow of energy is non-cyclic, linear and unidirectional as the energy lost is not available to the previous trophic level
Nutrients moves in a cyclic manner between living organisms  and their physical environment
In energy flow, the ultimate energy source is the sunlight
Nutrient source always belongs to earth often atmosphere or lithosphere (reservoir pool)
During energy flow, energy is lost at each trophic level primarily as heat and used by organisms for respiration
Nutrients are recycled in an ecosystem without any loss
Energy from sun enters as light and exits an ecosystem mainly as heat
Nutrients such as carbon, nitrogen, phosphorous, sulphur etc present on earth are used, recycled and reused in an ecosystem
In energy flow, the energy is not  recycled during decomposition by decomposers, but is released mostly as heat
Microorganisms such as bacteria, fungi etc (Decomposers) plays a prominent role in cycling of nutrients without any loss
07:12

10 Differences between Conventional and Nonconventional sources of energy

Energy is defined as the capacity of a substance or a body to do work. Conventional sources of energy refer to the energy sources that have been traditionally used for many years. These energy sources are non-renewable and likely to be depleted due to its extensive use. Non-conventional energy sources are alternate energy resources to the conventional energy resources but in limited use due to lack of feasible technology.
10 Differences between Conventional and Nonconventional sources of energy
Conventional vs Non conventional Sources of Energy 
Conventional Energy Resources
Non-conventional  Energy Resources
It refers to the traditional sources of power or energy like firewood, coal, petroleum etc
It refers to recently developed sources of energy from sun, wind, tides etc
Energy sources are non-renewable
Energy sources are renewable
Comparatively expensive to maintain, store and transport
Initial expenditure for energy generation is high but cheaper in the long run
Following established technologies for energy production
Require new feasible technologies; still under research and development
Energy sources which are fixed in nature
Generally energy sources are not be fixed in nature
Available in limited quantity; exhaustible
Available in plenty; inexhaustible
Causes large scale pollution; not eco-friendly
Generally Eco-friendly source of energy
Causes green house effect and major culprit in climate change and has serious health consequences
No such issues as energy source is ecologically safe
At present, widely used energy source
Presently limited use; feasible technologies are yet to be developed
Examples: coal, petrol, diesel, LPG etc
Examples: solar energy, wind energy, hydroelectric power etc
10:08

Difference between Blood serum and Blood plasma (Blood serum vs Blood plasma)

Blood is a fluid connective tissue. It is an extremely complex substance carrying a wide variety of cells and substances to all areas of he body. Blood is often described as seat of the soul since it performs several vital functions of the body . A normal  healthy man has about 5.5 litres of blood.

Blood is formed of plasma and formed elements such as RBC, WBC and blood platelets

Functions of blood:
  •      Regulate body temperature. 
  •      Maintains a constant pH and water balance 
  •      Defence against pH and water balance 
  •      Transport digested food materials, respiratory gases and waste materials
Difference between Blood serum and Blood plasma (Blood serum vs Blood plasma)

Plasma is the matrix or the extracellular fluid of the blood tissue. It is straw coloured, non living, and slightly alkaline aqueous fluid with pH of 7.4. About 30-35% of blood is plasma.
Plasma contains: Water (About 91%), Plasma proteins (about 7%), Organic substances and inorganic substances (2%)
Functions of Plasma:
  • Transport: Plasma transport the digested food products like glucose, amino acids, fatty acids, etc.
  • Body immunity: one type of globulins called immunoglobulins act as antibodies. They inactive invading microorganisms and their toxins.
  • Prevention of blood loss:  Fibrinogen helps in blood clotting and thus prevents blood loss. During blood clotting the soluble fibrinogen is converted into insoluble fibrin.
  • Retention of fluid in blood
  • Maintenance of blood pH: Plasma proteins act as acid base buffers and thus maintain the blood pH by neutralizing strong acids and bases.
  • Regulation of body temperature: Plasma helps in the uniform distribution of heat all over the body, and in conducting heat to skin for dissipation.
Difference between Blood serum and Blood plasma 
( Blood serum vs Blood plasma)
Blood plasma
1. Fluid portion of the blood in the form of matrix i.e., fluid-blood corpuscles.
2. Flas fibrinogen and other clotting materials
3. Take part in blood clotting
4. It is straw colored clear liquid
Blood serum
1. Fluid collected after colt retraction
2. Does not have all these
3. Does not take part in blood clotting
4. It is pale yellow colour
10:55

10 Differences between Cell wall of Gram positive and Gram negative Bacteria

 Gram staining  is a special technique which is used to stain bacteria. This technique was developed by Christian Gram in 1884. The stain  stain used in Gram staining is called Gram stain. Chemically Gram stain is a weakly alkaline solution of crystal violet or gentian violet.

On the basis of cell wall structure and its staining ability with Gram stain, bacteria are grouped into two categories. They are Gram positive bacteria and Gram negative bacteria
Cell wall of Gram positive bacteria
Cell wall of Gram negative bacteria
Cell wall is single layered and primarily made up of peptidoglycan
Cell wall is double layered and with an outer membrane outside to Peptidoglycan layer
Gram positive cell wall retain the primary stain of Gram staining (crystal violet) and appear purple after alcohol treatment
Gram positive cell wall lose the primary stain of Gram staining (crystal violet) after alcohol treatment; and appear pink with counter stain (safranin)
Thick peptidoglycan layer of about 20 to 80 nm
Peptidoglycan layer thin and single layered (about 5 to 10 nm thick)
Periplasmic space is absent
Periplasmic space* is absent
Outer membrane is absent
Outer membrane is present outside to Peptidoglycan layer (about 7.5 to 10 nm thick)
Teichoic acid is present
Generally Teichoic acid is absent
Generally **Porins are absent
Porins are present


Very low lipid content (2-5%)
Very high lipid content (15-20%)
Generally Lipopolysaccharide (LPS) is absent**
Lipopolysaccharide (LPS) is present
Lysozyme degrade peptidoglycan wall cause lysis of cell (sensitive to lysozyme)
Lysozyme cannot degrade Gram negative bacteria as Peptidoglycan is protected by outer membrane
(resistant to lysozyme)
Example of Gram Negative Bacteria


* The region between cytoplasmic and outer membrane of the Gram-negative bacteria is called the periplasmic space
*Porins produce large, open, water-filled channels that allow the influx of normal, hydrophilic nutrient molecules and the efflux of waste products but exclude many antibiotics and inhibitors
 **only one Gram-positive organism, Listeria monocytogenes, has been found to contain LPS