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Saturday, April 17, 2010

Set free to accomplish goal

Set free to accomplish goal
Creativity is key to succeed in any mission.It enables a person to think in a dynamic way and finally accomplish his or her goal.A person becomes creative when he or she is allowed to work freely in a peaceful way with no hindrance or obstacles at all.SO,I am fully convinced with the statement that says "People accomplish more when they are allowed to do things in their own way."
A child is born free when he comes to this world.Initially,the mind of child is in inert stage but slowly he gains proper knowledge from the world.The child grows into adult with the passage of time and finally gains more information.His creative power increases.If he is allowed to do things in his own way then he can become a perfect individual of tomorrow.A child has many goals and aims in his life.He wants to do something very unique.He sets his goal in very high limit and put great efforts to achieve it.If the environment allows him to work freely then he can achieve those goal quite easily.But as the world is full of disturbances and hindrance ,so it becomes difficult for child to succeed in his task.
There are few people who have achieved their goal and become known through out this world.They became model to this world as they were able to make such discoveries that helped in the improvement and betterment of society.Moreover their creation was unique and extraordinary.They were able to achieve these things as they were allowed to do works in their own way.Like,Sir Issac Newton formulated Gravitational Law when he saw an apple fall from the tree.Similarly,Galileo discovered telescope when he wished to see heavenly object.Likewise,Sir Albert Einstein established relation between mass and energy which has been beneficial to human kind till now.There are many examples which has reflected the necessity of leaving a person to their free state to achieve goal.They have become successful in getting their target when they were liberated.
However,some of the people might think that people can achieve goal more perfectly when they are bound with a certain perimeter so that they don't have to worry of the worlds problem.But in my opinion,those captured people can only limit their mind within that boundary.They are unable to free their self and their creativity gets down which hinder their development to accomplish their goal.The more we try to limit ourselves the more violent we become.Limiting ourselves within small boundary is the main cause of violation.The more we think the more we are able to win over this world and shower this world with full of presents like our few ancestors did.
Finally,a free mind is a successful mind.To accomplish target it is necessary for the person to feel himself free.Then only it is possible to gain their desire.Restriction is not the key for development.As human beings did not restrict themselves to few invention;thus we are now able to surf the whole universe within fraction of seconds.Therefore,people accomplish more when they are allowed to do things in their own way.

Sunday, April 11, 2010

Sex linked Inheritance,Linkage with gene and chromosome

LINKAGE :
The persistent association of genes located in same chromosome which are inherited together in same position from one generation to another is called Linkage.Gene present in the same chromosome is called linked gene.
The main significance of linkage is that it reduces the possibility of variation in gametes unless crossing over takes place.
CHROMOSOME THEORY OF LINKAGE:
Morgan and castle formulated the Chromosome theory of Linkage according to which he listed the following points:
1)Gene which show phenomenon of linkage are located in same gene.
2)They are arranged in linear fashion in the chromosome.
3)The strength of linkage depends upon the distance between the linked genes in the chromosomes.The closely located genes show strong linkage while the widely located genes show weak linkage.
4)The number of genes per individual is far more than the number of chromosome pair.Thus,each chromosome bears many gene.
5)Linked gene remain in their original combination during the course of inheritance.
TYPES OF LINKAGE:
1)COMPLETE LINKAGE:
The linkage in which character are inherited together in their original combination for two or more generation in continuous and regular fashion is called complete linkage.There is always parental combination's and no any recombination.Margon reported complete Linkage in Drosophila.
Morgan crossed a wild Drosophila having grey body and normal wings(BBVV)with a black body and vestigial wing(bbvv).All the hybrids in F1 generatio have grey body and normal wings(BbVv).when F1 male hybrids are crossed with a double recessive female having black body and vestigeal wing(bbvv),in F2 generatio the offspring of 2 types in equal proportions are produced.These offspring's resembled their grandparents.
Parents Grey,Normal * Black,Vestigeal
BBVV bbvv
Gametes BV * bv
F1 generation BbVv

Test cross F1 male grey,normal * female black,vestigeal
BbVv bbvv
gametes Bv bv * bv

Test cross Grey ,normal * Black,Vestigeal
ratio BbVv bbvv
50% 50%
The result indicates that the grey body character is inherited along with normal wings.Its Suggest that the genes are linked together.

2)INCOMPLETE LINKAGE:

Incomplete linkage is defined as the separation of linked gene due to crossing over.In this type of linkage,genes are widely located in the chromosome. Incomplete linkage was demonstrated by Hutchinson in maize plant.He crossed a maize plant having coloured and full seeds(CCSS)with Colourless and shrunken seeds(ccss).The F1 hybrids appeared with coloured and full seed(CcSs).When the F1 hybrids are crossed with double recessive parents
(ccss),they showed four types of progeny in the following ratio:

Parents Coloured,Full * Colourless,Shrunken
CCSS ccss
Gametes CS * cs
F1 hybrids CcSs

Test cross F1 coloured,full * Colourless,Shrunken
CcSs ccss
Gametes CS Cs cS cs * cs
Progeny Coloured full coloured shrunken colourless full colourless shrunken
CCSS CcSs ccSs ccss
48% 2% 2% 2%

SEX LINKED INHERITANCE:
There are two types of chromosomes in living organism.They are:Sex linked Inheritance
1)Autosomes:
Chromosomes bearing genes for somatic organs are autosomes.There are 22 pairs of autosomes in human beings.genes linked with the autosome shows autosomal Linkage.
2)Sex chromosome/Allosome:
Chromosome that determine the sex of the species is called sex chromosome.Human has one pair of sex chromosome.Sex chromosome in female is X and in male is Y.Gene linked with sex chromosome show sex linkage.In most of the animal including human beings,female have two alike rod shaped chromosome"XX" while male has one rod shaped chromosome"X" and another hooked shaped chromosome"Y".
Genes located in X chromosome is sex linked gene and the pattern of inheritance of such gene is called sex linked inheritance.These genes are inherited along with X chromosome.In most of the animals,Y chromosome is genetically inert.it may or may not contain genes.Genes present in Y chromosome are called holandric genes.

CRISS CROSS INHERITANCE:

The inheritance in which parents transmits their sex linked traits to their grandchildren of same sex through their offspring of opposite sex is called criss cross inheritance.For eg:Father transmits their sex linked traits to their grandson through daughters.

SEX LINKED INHERITANCE IN DROSOPHILA:

Sex linked genes were reported for the first time by American Zoologist T.H morgan while studying colour in Drosophilla melanogaster.Morgan,while working in Drosophilla found a male fly with white eye colour in the culture of red eye Drosophilla.The normal eye colour of Drosophilla is red.Actually the gene for white eye arose as a mutation of gene for red eye.Morgan and his associates,from numbers of crosses found that the inheritancce of eye colour in Drosophila was associated with sex chromosome of the parents.Drosophila has a pair of sex chromosome.Female has alike rod shaped chromosome XX whle male has One rod shaped chromosome X and another hook shaped chromosome Y.
Morgan crossed a red eyed female and white eyed male.The F1 hybrid were red eyed out of which half were male and half were female.When the red eyed male and red eyed female of F1 generation were intercrossed then all the F2 females were red eyed and out of two F2 males half were red eyed and half white eyed.

Parents Red eyed female (RR) * White eyed male(WW)
Gametes XR XR XW Y

F1 hybrids XRXW XRXW * XRY XRY

Red eyed female Red eyed male

F1 hybirds Red eyed male(XRY) Red eyed female(XRXW)
Gametes XR Y * XR xW
f2 Hybrids XRXR XRXW XRY xwY
Red eyed female Red eye male white eyed male

Thus,this shows that the white eye character is transmitted from grandfather to grandson through daughter.

CHARACTERISTICS OF SEX LINKED INHERITANCE:

1)Criss cross inheritance:
It is type of sex linked inheritance in which parents passes their sex linked traits to their grand child of same sex through offspring but of opposite sex.
2)Sex linked traits are recessive.
3)Males suffer more from sex linked disorders.
4)Recessive gene can express in female only in homozygous state otherwise female are only carriers.
5)Traits governed by sex linked recessive gene:
a)Produce disorders in male.
b)Express when represented by single allelle because Y-chromosome don't carry any allele.
c)Seldom occurs in father or son.
d)Fail to appear in female unless their father also posses the same and mother is carrier.
6)Traits governed by sex linked dominant genes:
a)Produces more disorder in female.
b)All the femal offspring will exhibit if father produces the same.

SEX LINKED INHERITANCE IN HUMAN BEINGS:
1)COLOUR BLINDNESS:
It is a condition in which a person is unable to distinguish between red,green or both colours from other colours.It is also known as Red Green colour blindness.or Daltanism.THe gene for this red green colour blindness is present on X chromosome.
eg.
When a colour blind man(XcY) marries a normal woman(XX) then all their male and female children are normal but the female children are carrier.If carrier female marries a normal male than two normal visioned female,one normal visioned male and one colour blind male is produced.
Parents Colour blind man(XCY) * Normal woman(XX)
Gametes XC Y * X X
F1 hybids XCX XCX XY XY
carrier females normal male

Carrier females(XCX) Normal male(XY)
Gametes XC X * X Y
F2 hybrids XCX XCX XCY XY
Carrier female colour blind Normal male
male
2)HAEMOPHILIA(BLEEDERS DISEASE):
A disease in which suffering people donot have ability for blood clotting is called Haemophilia.As Queen Victoria of England was its carrier it is also known as Royal disease.The pattern of inheritance is criss cross.
If a normal woman marries a haemophilic man then both the F1 sons are normal whereas F1 daughters are normal but carrier.When carrier female marries normal male then the F2 daughters are normal whereas among two F2 sons,one son is normal and the other is Haemophilic.
Parents Normal woman(XX) Haemophilic man(XHY)
Gametes X X * XH Y
F1 hybrids XHX XHX XY XY
Carrier female normal male

Parents Carrier female (XHX) Normal male(XY)
Gametes XH X * X Y
F2 hybrids XHX XX XHY Xy
Carrier female Normal female Haemophilic maleNormal Male

Friday, April 9, 2010

Pollination:Self and Cross Pollination

Pollination:Self and Cross PollinationPOLLINATION:
Pollination is transfer of pollen grains from anther to stigma of same or another flower of same or different plant with or without the help of external agencies is known as pollination.The self pollinated flowers are generally small,inconspicuous,colourless,odourless and nectarless.

TYPES OF POLLINATION:

1)SELF POLLINATION(AUTO GAMY):
The transfer of pollen grains from anther of a flower to the stigma of same or genetically similar flower is called self pollination.

CONDITION FAVOURING SELF POLLINATION:

1)HOMOGAMY:
This is the condition where the anther and stigma of bisexual flowers mature at the same period.
2)CLEISTOGAMY:Pollination:Self and Cross Pollination
Some bisexual flowers never open but remains closed which finally favour the self pollination.
Eg:ground nut
ADVANTAGES OF SELF POLLINATION:
1)It preserve the parental character.
2)It does not need any external agency.Hence shows greater re abilities.
3)It is necessary for species which are at great distant from each other.
4)It is advantageous to those plants which do not produce nectar and juices.
5)It is more economical as it does not consume energy for large population.
6)Pollen grains are not wasted.
7)Maintains the purity of races from one generation to another as no variation takes place.
DISADVANTAGES OF SELF POLLINATION:
1)The useful characters can not be introduced.
2)The undesirable characters do not eliminate.
3)The offspring are readily susceptible to disease.
4)It does not reveal any variability so they may fail in long run.
5)Continuous self pollination can lead to death of species.
6)No variation are produced as a result of no evolution taken place.
7)Weak progeny are produced.

TERMS USED: GEITONOGAMY:
Pollination between flowers of same plant is called geitonogamy.It may require external agency like insects,winds etc.

XENOGAMY:
Pollination between flowers of different plant is called xenogamy.

2)CROSS POLINATION(ALLOGAMY):

cross pollination is transfer of pollen grains from anther of one flower to stigma of genetically different flower.Cross polination is accompanied with external agencies like wind,water,animals etc.

EXTERNAL AGENCIES THAT BRING CROSS POLLINATION: 1)ANEMOPHILY:
Pollination which takes place by the help of wind is called anemophily.Wind picks up the pollen grains from the dehisced anther of a flower and drops them on the stigma of other flowers.
CHARACTERISTICS:
a)Anemophilous plants grow in large group.This ensures the pollination of flowers of all the plants.
b)In many herbaceous plants the flowers are produced above the fooliage.This ensures the exposure of flowers to the wind.
c)in deciduous anemophilous trees,flowers are produced before leaves(Peach,apple).
d)A high proportion of pollen grains are wasted in wind pollination.Therefore,plants produce large qunatities of the pollen.
e)Pollen grains are small,light or dusty and can be blown to large distances.
f)Pollen grains are light and inwettable.
g)In anemophilous flowers,the non essential floral organs are either absent or reduced.This make the flowers small,inconspicuous and devoid of colour,nectar or smell.

2)HYDROPHILY:
The pollination which takes place by means of water is known as hydrophily.It occurs only in aquatic plants.however,many aquatic plants with emerged flowers have other modes of pollination.
Eg:Lemma,Zostera,Vallisneria
TYPES OF HYDROPHILY:
a)HYPOHYDROPHILY:
It occurs below the surface of water.
Eg:Zostera,Ceratophylum,Hydrilla
b)EPIHYDROPHILY:
It occurs over the surface of water.
Eg:Vallisneria

3)ZOOPHILY:
The pollination which takes place by the means of animal is known as zoophily.It is of different types:
a)ENTOMOPHILY:
The pollination by means of insects is known as entomophily.
CHARACTERISTICS:
i)The flowers are large and bright in colour;and if small,they are grouped into inflorescence.Eg:Marigold
ii)They have scent and nectar.
iii)the pollen grains are large with sticky wall.
iv)Some flowers like violet,pansy and orchids have bright lines and spots on their petals which help the insects to the nectar.

b)ORNITHOPHILY:
Pollination that takes place with the help of birds is known as ornithophily.
Eg:Bombax,Begonia,Butea monosperma(flame of forest)
FEATURES:Pollination:Self and Cross Pollination
i)The flowers produces large amount of nectar.
ii)The corolla is funnel shaped which enable the bird to sip the nectar.
iii)The petals are of bright colour like red so that they can be seen from large distances.
iv)the stigma are sticky.

c)CHIROPTEROPHILY:
The pollination that takes place with the accompany from bat is known as chiropterophily.
Eg:Anthocephalos cadamba
CHARACTERISTICS:
i)The flowers are of dull colour.
ii)The flower consists of large amount of nectars and juices then ornithophilous flowers.
iii)The flower produce large number of stamens.

d)MALACOPHILY:
The pollination that takes place by the support of snail is called malacophily.
Eg:Arisaema(Snake or cobra plant) and arum lilly

DEVICES TO ENSURE CROSS POLLINATION:
1)DECLINY OR UNISEXUALITY:
This is the condition where the plants are dioecious(unisexual)which unable them to cross pollinate.
2)DICHOGAMY:
This is the condition in bisexual flowers where the anthers and stigma mature at different time.Dichogamy is of two types:
a)PROTOGYNY:
stigma matures earlier than anther of same flower.Eg:Mirabilis
b)PROTANDRY:
Anther mature earlier than stigma of same flower.Eg:cotton,sunflower
3)SUPPRESION OF ONE SEX:
In some bisexual flower,one of the two sex organ(either stamen or carpel)is completely suppressed and becomes sterile.
4)PREPOTENCY:
In certain plants pollen grains of one flower germinate on the stigma of another flower more rapidly than the same one.
5)SELF STERILITY:
Pollen grains of a flower are incapable of completing growth on the stigma of same flower due to mutual inhibition.
6)HETEROSTYLY:
This is the condition of occurrence of two or more than two types of flowers which have different lenth of styles and stamens.
Eg:Oxalis(trimorphy),Primula(dimorphic)
7)HERKOGAMY:
In certainn flower there may be some physical barrier between anther annd stigma so that self pollination becomes impossible.
Eg:Calotropis
ADVANTAGES OF CROSS POLLINATION:
1)Useful characters can be introduced in plants.
2)Undesirable characters can be elimated.
3)It increase the adaptability of varieties towarsds the new environment.
4)The seeds produced are usually large and more vigorous.
5)A phenomenon of hybrid vigour can be observed in this method.
6)Seed production never falls below an average minimum.

DISADVANTAGES OF CROSS POLLINATION:
1)It depends on external organisms for pollination to occur.
2)It is less economical.The plant consume large amount of energy in production of large no of pollen grains.
3)Some of very good characters of variety are likely to be spoiled.
4)Due to cross pollination,some undesirable characters can remain in variety.
5)It fails in oxalis.
6)Pollen grains are lost.

Thursday, April 8, 2010

Mutation with Ploidy

Mutation with PloidyMUTATION:
Mutation is sudden change in the hereditary of an organism due to change in number of chromosome, structure of chromosome or change in molecular level of DNA.
Mutation was coined by Hugo De Vries, a Dutch Botanist. He worked on Evening Primrose and observed 834 mutation out of 54343 plants.
Mutation which occurs naturally is called spontaneous mutation where the mutation which occurs artificially by chemicals or physical agents are called as induced mutation. The agents that induce mutation like mustard gas, x-rays, alpha, Betta or gamma rays are called mutagens.The product of mutation is called mutant.

TYPES OF MUTATION:

1) MICRO MUTATION/GENE MUTATION/POINT MUTATION:

Gene mutation is defined as change in the structure of individual gene.It induces just one or two bases in DNA molecule.Thus its is also called as Point Mutation.Gene mutation occurs due to following change in DNA and RNA:

a) Frameshift Mutation:
The mutation which is caused by either addition or deletion of nitrogenous bases of DNA or m RNA is called as Frameshift Mutation.One deletion is neutralized by one addition or vice versa.
i)Addition Mutation:
The point mutation caused by the addition of one base pair of a gene is called addition mutation.
Eg:Addition of G on base sequence:
GAT GAT GAT
addition of G
GAT GGA TGA
ii)Deletion Mutation:
The point mutation caused by deletion of one base pair of gene is called deletion mutation.
Eg,Deletion of G on base sequence
GAT GAT GAT
? deletion of G
GAT ATG ATG

b) Substitution Mutation:

One base pair replaced by a different one is called substitution mutation.It is of two types:
i) Transition:
The mutation which occurs by the substitution of one purine by another purine or one pyrimidine by another is called Transition.
Purine(A,G)
Pyrimidine9C,T0
A--G
C--T
ii)Transversion:
The mutation which occurs by the substitution of one purine by another pyrimidine or vice versa is called Transversion.
Eg;
A -T
C-G

2) CHROMOSOMAL MUTATION/MACRO MUTATION/LINE MUTATION

The mutation which is caused by the change in structure or number of chromosome is called chromosomal mutation.It is of two types:
a)Chromosomal abbreviation:
The mutation which is caused by the change in the structure of chromosome is called chromosomal abbreviation.These are of following types:
i)Deficiency:
Loss of terminal segment from a chromosome is called Deficiency.Eg
ABCDEF-ABCD
Ii) Deletion:
Loss of intercalary segment of chromosome is called Deletion.
Eg.
ABCDEF-ABEF
iii)Duplication:
Sometime the part of chromosome gets repeated in the same chromosome called duplication.Eg
ABCDEFGH-ABCDEFEFGH
Iv)Inversion:
Segment of chromosome being inverted and reunited is called inversion.
Eg:
ABCDEF?ADCBEF
v)Translation:
Exange of segment between non homologous chromosome is called translation..
Eg.
ABCDEFGH/MNOPQRST?ABCDEFST/MNOPQRGH

b)Genomatic mutation or Ploid:

Mutation caused by the change in the number of chromosome is called Ploidy or Genomatic mutations.It is of following type:
A)ANEUPLOIDY:
The addition or loss of one or more chromosome from the complete set is called Aneuploidy.Thus the total number of chromosome is not an exact multiple of the haploid number(n).
Eg(2n+1) Trisomy or (2n-1)monosomy

TYPES OF ANEUPLOIDY:
1)Hypoploidy:
Loss of chromosome for complete set.It is of following types:
i)Monosomics:
Loss of one chromosome from complete set is called monnosomics.It is represented as 2n-1.
ii)Nullisomic:
Loss of single pair of chromosoms from a pair of complete set is called nullisomics.Its is represented by 2n-2.

2)Hyperploidy:

Addition of chromosome in complete set.It is of following type:
i)Trisomic:
Addition of one chromosome is called trisomic.It is represented as 2n+1.
ii)Tetrasomic:
Additon of a pair of chromosome is called tetresomic.It is represented as 2n+2.

B)EUPLOIDY:
It include addition or loss of complete one set or more than one set of chromosome in diploid organism.The total number of chromosome is exact multiple of halploid number.They are of following type:
a)Monoploidy:
It involves loss of one set of chromosome from a diploid set resulting offspring having only one set of chromosome.
Eg:Male wasp,bee
b)Polyploidy:
Addition of one or more sets of chromosome is called polyploidy.Organism with more than two sets of chromosomes is called polyploidy.
Types of Polyploidy:
i)Autopolyploidy:
Autopolyploidy are those polyploids which are derived from the multiplication of the same basic set of chromosome.Autopolyploidy is formed due to replication of chromosomes during interphase and separation of chromatids during anaphase but fails to cytoplasmic cleave during cytokinesis.Autoploids are more fertile,vigour and large sized.
If a diploid species has two sets of chromosomes (AA) an autoploid willl have four similaf genome(AAAA)
Eg:Plum,Strawberry,grapes
ii)Alloploidy:
The polyploidy formed due to doubling of chromosomes number in a F1 hybrid which is derived from two distinct species is called alloploidy.
SpeciesX * SpeciesY
AA BB

AB diploid F1 hybrid

AABB

Cause of polyploidy:

It occurs in nature due to failure of chromosome to separate at the time of anaphase either due to non disjunction or due to non formation of spindle.
Advantages of Polyploidy:
1)Polyploidy is often associated with advantageous features such as increased size,hardness and resistance.This is called hybrid vigour.
2)Polyploidy is one of the source of Variation and help in evolution of new Varieties.
3)Seedless variety of watermelon,tomatoes,grapes etx have been produced by triploids.
4)Desease resistant and high yielding species of crop plants such as hybrid wheat,hybrid paddy are produced by allopolyploidy.
5)Polyploid plants have more morphological genetical and physiological advancement over a normal diploid plant.
6)Polyploid plant often faces the ecological hazards more boldly.

Reason for Triticum aestivum to become Hexaploid:
A Hexaploid species of wheat was artificially synthesized in 1946.A species of wheat Triticum monococcum(2n=14) was bred with wild grass Aegilops speltoids(2n=14) to produce a different species of wheat called emmer wheat(Triticum durum 2n=28),a tetraploid condition. Emmer wheat is again crossed with another species of wild grass Aegilops squarrosa(2n=14) to produce the wheat Triticum aestivum (2n=42) a hexaploid(6n) condition.
Triticum monococcum X Aegilops speltoids
2n=14 2n=14
Triticum durum
4n= 28

Triticum durum X Aegilops squarrosa
4n=28 2n=14


Triticum aestivum
6n=42
Hexaploid condition

ARTIFICIAL INDUCTION OF POLYPLOIDY:
Conchicine is the mostly and widely used chemical for artificial induction of polyploidy.It inhibits the formation of spindle fibre during mitosis.It is greatly used in horticulture because plants treated with it are more resistant.

CAUSES OF MUTATION:

Mutation may occur naturally and is called spontaneous mutation.But if the mutation is induced artificially with the help of chemical agents then it is called induced mutation.The main cause of mutation is chemical agents like mustard gas,X-rays,UV radiations etc called mutagens.These chemical agents are responsible for causing mutation.

MUTATION FREQUENCY:

The rate at which mutation occurs is called mutation frequency.It is very low in most organism.Genes with rapid mutation rate is called mutable or unstable gene.

ROLE OF MUTATION IN EVOLUTION:

1)Mutation provides a bulk of hereditary variations on which natural selection operates.
2)Mutation helps the organism to adjust in the new environment condition.
3)Various new plants of desired character have been created by mutation.
4)Useful characters can be introduced in the organism.
5)High production of disease resisting varieties of crops.
6)Mutation are useful for understanding the basic principles of inheritance.

RESULTS OF MUTATION:
Mutation produces different types of effects like lethal,advantageous ,neutral visible or invisible.Mutation may produce sudden and large changes or may produce small and insignificant changes.the mutation that produce any significant visible changes are detected and the mutations that fail to produce any phenotypic variation are lost undetected .Certain mutation induce physiological changes.they may influence the inability or fertility of organism.
A mutation generally results in the loss of function of genes such as:
1)Mutation changes the sequence of nitrogenous bases in the gene that cause the change in codons and the alters the sequence of amino acids.Therefore,the mutated polypeptide chain may have modified or reduced or no functional activity.
2)Mutation may lead to the formation of a termination of an incomplete polypeptide chain.This lead to the loss of normal functioning of genes.

Wednesday, April 7, 2010

Mobiles:Fashion or need

Mobiles:Fashion or need
Mobiles are the devices through which communication has become easier and faster.It is an electronic device used for mobile telecommunication over a cellular network of base stations known as cell site..In this modern world ,it is useless to tell what mobile is because every one is so familiar with it in day to day life.From morning to night, people use it.Mobiles have become a true friend to everyone.Life can not be imagined without a mobile phone today.This reflect how important mobile has become.More then this,mobile has become an integral part of our life and thus it has made us dependent upon it.

A mobile has got many advantages.Communication has become faster and much easier due to mobile.Precious time is saved by use of mobile.Nowadays,many software's are also included in mobile set itself.So,mobile has become quite versatile.Not only communication but different games are involved in mobile phone.Similarly,mobile phones can be used as a television also.Chinese has invented such mobile devices through which television can also be accessed easily.Mobile phones market is increasing day by day.It has been estimated that over 4.6 billions mobile will be sold by 2009.So, its popularity is increasing day by day.Not only mobiles have made life easier,it has also helped to improve economic condition of many countries.Mobile industries are being established day by day.Many people are keen in learning about mobile technology.Establishment of various mobile industry has given employment opportunity to many people.Similarly,the country's economic condition has been boost up.For example:China has been successful in increasing its economy to 9% due to development in technologies and mobile is one of the them.In world more than 2 billion people are using Chinese mobiles.This shows how mobile help to improve economic condition.

Despite of these aspects question now arises whether mobile phones are being used for communication purpose or for fashionable purpose?Young generations are buying expensive mobiles for showing purpose rather than communication.If question is asked to them ,then reply comes in this way:
"My friend brought an N-series latest mobile,So I must also buy one otherwise I will lose my prestige in front of him."This has become reason for global market of mobile rather than its advantage of communication.Mms has promoted porn pictures.So,mobiles phones are being misused.While manufacturing mobiles phone,the inventor must take all these thing in mind and manufacture mobiles phone or else the young generation will be useless.Similarly,chating with friends for more than hours and hours has dawdled the time of student.As student are future of nation,so development of countries lie in the hand of mobile phone manufacturer.Mobile manufacture company must not create such expensive mobiles.This must be controlled.

IMPROVEMENT IN TECHNOLOGY

21st century is called as "Era of Science and Technology".Is it right to tell this?Have you ever though this before why people call this era as" Era of Science IMPROVEMENT IN TECHNOLOGYAnd Technology?"But with no further dilemma in your mind:this is in fact age of Science and technology.There is no need to explain why?You can judge by yourself by looking around naked eyes.What do you see around?Don't tell nature and its beauty.Besides that what do you see?Its the creation of great Scientists.

You are able to access the whole world by staying in a room;you can know about the Universe by just changing the channel of your television;you are able to communicate with people staying at South pole ,you being in North pole;you can go from one place to another without any discomfort...and lots and lots of more which you are using is boon given to us by the great Scientists.Life has become more easier,more faster and more safer which our forefathers were not able to observe.This reflect the development in technology.The development in technology has reached such height that it is difficult to think further improvement in technology.But hats off to those scientists who are continuously working day and night for helping ordinary people by bringing improvement in technology.

With advantages comes drawbacks.Einstein creation E=MC2 has been wrongly used by some dictators in making nuclear weapons.The invention of atom bomb is taking life of all living organism and destroying earth piece by piece .If this continues iIMPROVEMENT IN TECHNOLOGYn same ratio then we have to search another place to live.People are forgetting who they are and are behaving like animals who are even better than those humans who use their power in negative way.Killing each other for the sake of power is simply a cruel deed.People are fighting for short term pleasure and happiness.They are running behind wealth but they have forgotten the fact that when they rest in peace then they will take nothing with them.They will simply die taking nothing along with them.So,its useless to fight in name of wealth,fame cause these all are sort term things.

Despite all of this,the development of technology is so rapid that after few minutes new things are been discovered.The things which our ancestor could not use are been used by us and the things that we are not using will be used by our upcoming generation.This shows that improvement in technology is steady process which will take place till the end of Universe.There is no doubt that even after the end there will be a new beginning and beginning means further development of technology and finally its improvement.We human beings may leave this world but our creation such that technology will remain alive for ever and ever;and thus make us immortal.This shows how we have made our life safer and easier by discovering new technology and our willingness to invent more and improve them.

Tuesday, April 6, 2010

Opportunity and Time: important in bringing friends


There is a well known saying that time and tides wait for none.It is like arrow left from a bow i.e once,it is released it never returns.Similarly,opportunity is the chance to achieve new things.If opportunity is not grabbed within time then nothing is possible.Whether it is wealth or relationship time and opportunity plays a vital role in achieving both of them.So,in my opinion I disagree with the statement that "neither opportunity nor time can determine intimacy."

The flow of time can be compared with the flow of river.It can never be stopped.There is a life cycle going around and we are part of this cycle.Unless propeThere is a well known saying that time and tides wait for none.It  is like arrow left from a bow i.e once it is released,it never  returns.Similarly,opportunity is the chance to achieve new things.If  opportunity is not grabbed within time then nothing is possible.Whether  it is wealth or relationship time and opportunity plays a vital role in  achieving both of them.So,in my opinion I disagree with the statement  that r time comes, we can not do anything.Friends are one of the most important parts of human life.Man is social animal and to live in society he needs friends.To make friends opportunity and time has an essential role.Certain time comes when two people meet each other.After meeting with each other,it is up to them whether they become friend or not.Here,time plays a nice role.If that two people spend few days with each other then they can become friends but not true friends.To become close friends they have to spend many years.So,time plays a part to bring closeness among each other.When it comes in context of opportunity then there are certain moments when two people get a chance to speak with each other and then establish a relationship.

Similarly,time and opportunity helps a person to create a friendly environment.A person can make many friends but not true friends.Its only time that will decide who will stay for ever and ever.Like Adolf Hitler.a dictator of Germany and Musollini,an autocrat from Italy were considered as best friends.It was time and opportunity that made them close friends.The starting of World war II made them ever more close than before.Similarly,Albert Einstein ,the great scientist was a German but contributed to USA in the World War II.It was once again time and opportunity that made Einstein to move to USA and help the country.Similarly,capitalist and communist groups were also created on the basis of time.In addition to this,its opportunity and time that increases love,closeness among family members than other people.We love our family members more than we do to others because we stay more time with them.

However,some people might think that time and opportunity is just a thing.Friends can be made by looking at them;it is not essential to spend more time to make friends and opportunity is also not required.They are simply superfluous things.But the aftermath of such friendship is not long lasting,it is like love at first sight.Such friendship can not bring any love,affection,closeness or overall intimacy.Thus,time and opportunity has essence role in bringing happiness in life.

Finally,I would like to support the fact that time and opportunity together plays an important role in bringing intimacy.It is not possible to make true friends.Person must grab proper opportunity and wait for while to make good friendship and life lasting relationship.So,I disagree with the statement that" neither time nor opportunity can determine friendship."

Monday, April 5, 2010

Function of nerves and types of nervous system

Function of nerves and types of nervous system
PERIPHERAL NERVOUS SYSTEM:
The peripheral nervous system consists of nerves arising from brain called cranial nerves and from spinal cord called the spinal nerves.
A)CRANIAL NERVES:
There are 12 pairs of cranial nerves in man.These are arising from the ventral side of the brain.Each is given a name according to its distribution.Each is numbered with Roman numerical according to the order in which its superficial origin.The deep origin of a cranial nerve refers to its nuclei of origin and termination of brain.The Nature,distribution and functions of the cranial nerves with branches are as follows:

No. Name with main branches Origin from brain Distribution Nature Function
1 Olfactory Olfactory lobe Olfactory epithelium Sensory Smell
2 Optic Optic chiasma Retina of eyes Sensory Vision
3 Ocumulator Crura cerebri Four muscles of eye ball Motor Eye movement
4 Trochlear Mid brain Superior Oblique Motor Eye movement
5 Trigeminal Pons Varolii Eye,eyelids,tongue Both sensation
6 Abducens Pons Varolii External rectus muscle Motor Eye movement
7 facial Pons Varolii Palate tongue,lower jaw Both Movement salivation
8 Auditory medulla Internal ear cochlea Sensory Equilibrium in hearing
9 Glossopharyngeal Medulla Tongue,pharynx Both Taste,Salivation,Swallowing
10 vagus Medulla Larynx,Heart,lungs Both Movement
11 Spinal accessory Medulla pharynx,larynx,neck Motor Movement
12 Hypoglossal Medulla Neck and tongue motor Movement

Trigeminal is the largest cranial nerve whereas Vagus the longest cranial nerve.Nature of the Cranial nerve can be found out by following statement:
"Some Say Marry Money But My Brother SaY Bad Boy Marry Money"

B)Spinal Nerve:
There are 31 pairs of Spinal nerves.Paired Spinal nerve emerges from sides of spinal cord and find their way through the vertebrae into the corresponding muscle segments.The spinal nerves are as follows:
1)Cervical:8 pairs(neck)
2)thoracic:12 pairs(in thorax)
3)Lumbar :5 pairs(in the upper part of abdomen)
4)Sacral :5 pairs(in the lower part of abdomen)
5)Coccyxgeal:1 pair(in the tail region)
Each spinal nerve carries both sensory and motor impulses.It originates by two roots-a dorsal root with a ganglion outside the spinal cord and a ventral root with no external ganglion.The dorsal root contains mostly sensory fibres,carrying afferent impulses to the spinal cord.

AUTONOMIC NERVOUS SYSTEM:
The involuntary nervous system which controls and coordinates various function that are carried independently in the body like control rate of heartbeat,the movement of alimentary canal is called autonomic nervous system.It consist of two systems:
1)SYMPATHETIC NERVOUS SYSTEM:
IT is also called thoracic-lumbar outflow because its preganglionic fibres join the spinal cord only in the thoracic and lumbar region.It consists of 2 sympathetic nerves or chains running from the head to the end of sacral regions one on each side of the vertebral column.Preganglionic fibres arise from the spinal cord and pass through ventral roots of spinal nerves.The sympathetic nerves stimulate the adrenal glands to secrete adrenaline.The post ganglionic fibres of sympathetic nerve systems release adrenaline at their nerve endings,so these are called adrenergic nerve fibres.
FUNCTION:
Sympathetic nervous system stimulates increase in heart beat,dilates blood vessels in muscles but constricts peripheral vessels thereby increasing blood pressure,dilates the eyes and increases respiration but slows down the gastro intestinal secretion.
2)PARASYMPATHETIC NERVOUS SYSTEM:
It is also called cranio-sacral out flow because some of the cranial nerves and sacral nerves are involved.It consists of ganglia,preganglionic and post ganglionic fibres.The preganglionic fibres are joined to the cranial nerves of III,VII,IX,X and to the second,third and fourth sacral spinal nerves.So these form CranioSacral Outflow.These form Synapses with neurons of the parasympathetic ganglia.Parasympathetic ganglia are present either near or inside the visceral organs.These are isolated ganglia and are not interlinked to form a chain.
Post ganglionic ganglia are small sized axons of neurons of parasympathetic ganglia and supply smooth muscles and glands or visceral organs.these form a network in the wall of the visceral organs called Aurebach Plexus.Post ganglionic ganglia release acetylcholine in their nerve endings,so these are cholinersic nerve fibres.
FUNCTION:
Sympathetic and parasympathetic nerves supply the same organs but their effects are usually antagonistic(opposite).The parasympathetic stimulation slows down the heart beat,decrease blood pressure ,constricts the pupil of eye and bronchi but speed scretion of gastric tract.These are the opposite functions of sympathetic system.

Thursday, April 1, 2010

RESENT THE FLAWS IN OTHER

 RESENT THE FLAWS IN OTHER
Flaws are the mistakes that has been committed by us.Being a human being its natural to make mistakes.Mistakes made by us is very common and we often try to hide it.However some people might think that we realise our mistakes and accede it.But the fact is that we frequently resent the flaws to others.So, I agree with the statement that "we often resent in others the flaws that we possess".
No one is perfect in this world.So,its natural to commit mistakes by us.But we have the habit of concealing the truth so that we might not feel abase from others.We try to think ourselves superior than others.When we make the flaws we do not like to comment on it but when the same flaws is made by others then we keep on pointing the mistakes that they have made. Its the human nature.Pointing others is as simple as eating but realising is like lifting a mountain by your hand.Its very difficult to reveal the mistake in front of everyone.Very few people have the guts to reflect their mistakes.
Likewise,concealing mistakes are often to dangerous.It might lead to path of destruction and deterioration.Mistakes are like poison which may take life of the person who have committed that.Its very important to correct the mistake once performed rather than to repeat it.But we don't have the habit of realising it.Rather than doing that we simply blame others for the act.This things mainly happen in courts.The criminal who has performed the bad deeds escapes by the advocators who fight their case.They blame the charge of those villians to other innocent people.This happens in reality where truth is always concealed.Its very difficult to face the fact as they are always bitter.But once we have that habbit of facing the flaws we make then our life is enlighten just like Lord Buddha.Buddha was ordinary man but his act of facing the truth led him to immortality.
However,some people might consider that they always reveal their mistakes and ofter do not make flaws.But in my opinion they are non other than charlatan.They have ability to dupe the innocent people and consider themselves to be right always.But in reality they are non other than a fraud who must be punished more severely.Being human ,everyone wants to be perfect and feel superior but its impossible.So,the people who think this way must change their habit before its too late.
Finally,I would like to conclude by saying that we often try to pass our deeds to others than realising it and facing the aftermath.But the reality is the same what is mentioned above.As Adolf Hitler had to die when he made a mistake of sending his troops to Russia for war,just like that we have to face severe consequences if we do not realise from the mistake we make.So,its necessary for us not to blame flaws to other.Anyway,I am fully convinced with the statement "we often resent others for the flaws which we often possess."

ROBOTS:HELPER TO MODERN WORLD

ROBOTS:HELPER TO MODERN WORLDA robot is automatically guided machine cable of doing work on its own.The word robot can refer to both physical robots and virtual software agents.A robot is a machine that reduces human effort.Invention of robots is great achievement in human world.It has changed the meaning of mankind.Robots have proved to be boon to us.

Life has become easier due to robots.They look physically like human beings but lack mind.So,they can be called as human but without mind.They are right hand of human beings.They are helping us in each and every field.The things that can not be done by human beings ,can be done by robots.They can be found in every field.Scientists design robots on the basis of the requirement.ForROBOTS:HELPER TO MODERN WORLD general purposes they design simple robots whereas for complicated process they design robots with better programming.A robot can be found everywhere.It can be found helping us in household activities or can be found in industries performing heavy works.A robot can perform work which 100 workers can do.If comparison is done, robots perform work faster and with more accuracy than 100 workers.

Nowadays,robots are preferred in industry rather than workers.The industries are in great profit with the invention of robots.It is because the chairperson does not have to pay wages to his laborers .There is no worry of any strikes if robots are hired.Similarly,the chairperson does not have to give any holidays.Works are performed with accuracy and on time.So,robots are replacing humans.This can be considered as a problem.It is creating unemployment to several workers.So,these laborers might undergo strike.The government must understand this problem and act soon.Despite of this,use of robots are increasing rapidly.So,it won't be wrong in saying that robots have become an integral part of our life.It has become an honest slave for us.Within few year this world will be full of robots.

Robots can not be threat to us unless we provide them with wrong programming.So,thinking this that the robots will take over the world is simply apocryphal.The fact is that robots are menially a servant of human beings and not more than that.So,its useless to think about the increasing population of robots.How developed a robot might be but it can never replace the place of human beings.This earth is place to live for only living beings but not the creation of living beings i.e human beings.Simply,it can concluded that invention of human beings can only make our life simpler,easier and more comfortable.So,from all of the above discussion robots are the true helper of this modern world.

EITHER EDUCATION OR EXPERIENCE IMPORTANT

EDUCATION OR EXPERIENCES I
Education is system of gaining knowledge by learning again and again through various sources whereas experiences are the things which you learn after facing the things before.Although people might consider these to things to be correlated but the fact is that they are separate terms with distinct meaning.They can be compared just as water and ice.In my opinion,education is far more better than experience.

Education is a process of knowing something by virtue of learning.When a child is born,the first thing he gains is education from his mother.Then he goes to school and gains more education and develops his brain.Further he goes to colleges and finally university to gain information of various things.With the passing of time the child becomes a mature man and is able to deal with this world.The child prepare himself to become a citizen of country by education.Education is a key factor for the development of a person.Without education his life can be considered as animals life.The great leaders like Barak Obama are well educated and are able to run great and big countries.If they were simply experienced but not educated they wouldn't have reached that post today.

Similarly,experiences can be gained if you are educated.When you get education then only you can know of something.Thats the first step of experience i.e knowing somethings.With the passage of time you can gain experiences by facing the world.But you can not get education unless and until you learn it.Likewise,the gift of education can be gained in the form of experiences.The things which you learn when applied in life will give you a proper result and outcomes.Thats the true gift of education when you apply it for the development of country and betterment of people.

However some people might think that education and experiences are like two sides of coins.They are correlated.But in my opinion,they are like day and night,fire and water,ice and liquid.They might be considered to be correlated but are far different if detail analysis is done. Just like fire provides hotness and water provide coldness ;like wise education provides path for experiences.So,education and experiences can be considered to be different.

Face book dominating world

FACEBOOK:A GLOBAL CONNECTING SITE
Face book has become one the most entertaining and popular site currently used by FACEBOOK:A GLOBAL CONNECTING SITEpeople of all ages.It has established itself as one of the best communicating site.Face book is social networking site in which one can upload their images,add friends and send them messages.Created by Howard university students,Mark zuckerberg along with other two friends on February 2004,face book enables anyone to built complete application that members can choose to use.Face book has take global market.More then 200 million people has been using this application.

Face book has brought million of people together.This is its most advantageous feature.The friend which you have lost during your childhood is in your contact now.This has proved to be boon to us.Its phote sharing market has made people to know about each other more properly.Development of facebook has hinder progress of some other site like Hi5.The progress of face book is so much that it has recently earned 4 billion dollars.Such site has helped to improve the economic standard of the owner.Previously,face book was created only for Howard students.But now it is released all over the world.The various application available in face book has enabled full time entertainment for its visitors.So,there are many advantages of its been in top.

Despite of its controversies,its popularity is increasing day by day and rapidly.People are so keen in using face book that they have forgotten what their day to day life routine is.Face book has become a great threat to students.Most of the students all over the world are using this site.It is estimated that more than 6 millions people are using face book daily.If they ratio goes on then the whole world will be using this.Face book has become a threat to development of country.People working in office are currently using this chatting site and sharing their thoughts daily.It is good to communicate with people but spending whole day with this is not good.In this session of economic crisis,instead of working hard the workers are wasting their precious time.

So,using face book is good but spending all your precious time in using this is not acceptable.Thus,some countries like China has banned face book.So,it depends on the user how they utilize or take face book as.If they use it for time pass then they are simply killing their time.But if they are simply making a network then it is helpful to them for their coming future.It depends on how you use.Thus face book is one of the most globally dominated site that the people all around the world is using.