Sex Influenced Trait - Short note

Sex influenced trait occurs in both males and females but it is more common in one sex. It is controlled by an allele that is expressed as dominant in one sex but recessive in the other. This difference in expression is due to hormonal difference between the sexes. Pattern baldness is a sex influenced trait. Many more than women are bald. It is inherited as an autosomal dominant trait in males but as an autosomal recessive trait in females. A heterozygous male is bald but a heterozygous female is not. A woman can be bald only when she is...

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Reasons for Opposition - Islam

The Quraish were leading tribe in the Arabian Paninsula. They were used to idol worship that the Holy Prophet openly condemend. They took the teachings of Islam as an insult to their religion and the ways of their forefathers.   The location of the Ka'abah in Makkah gave them an important position as the custodians of the House. It was a source of income for them, particularly the priests, as the pilgrims to the Ka'abah would being rich gifts for their idols. In the rise of Islam, they saw the danger to their dignity and prestige...

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Reaction of early Muslims towards persecution

Reaction of early Muslims towards persecution        The Muslims of early days although limited in number, had very strong faith and belief in Allah and His prophet. They maintained this faith, regardless of the cosequences. For instance, the Muslim slaves who were tortured mercilessly by their masters never renounced their religion, and at times, lost their lives when given an alternative between idol worship and Islam.        The Muslims were always united under the leadership of the Holy Prophet...

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Discovery of Electrons - Cathode Rays of Properties

Discovery of Electrons:      At ordinary pressure the air inside the Discharge Tude do not conduct electricity even when the electrodes were connected to a source of very high potential of about 5000 volts.     If the pressure inside the tube is reduced and a high voltage of 5000 - 10000 is applied, an electric discharge is produced through the gas producing a uniform glow inside the tube. By reducing the pressure in the tube still further to about 0.01 tor thr original glow disappears. Rays are produced...

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Metabolism - Ananolism - Catabolism - Water

Metabolism:    All the chemical reactions taking place within a cell are collectively called metabolism. Metabolic processes are characterized as anabolism and catabolism.Anabolism:        Those reactions in which simpler substances are combined to form complex substances are called anabolic reactions. Anabolic reactions need energy.Catabolism:         Those reactions in which complex molecules are broken down into simpler ones are called catabolic reactions. Catabolic reactions...

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Reading Comprehension - Passages - Practice With Exercise

Democratic societies from the earliest times have expected their governments to protect the weal against the strong. No 'era of good feeling' can justify disc haring the police force or giving up the idea of public control over concentrated private wealth. On the other hand, it is obvious that a spirit of self denial and moderation on the part of those who hold economic power will greatly soften the demand for absolute quality. Men are more interested in freedom and security than in an equal distribution of wealth, The extent to which Government...

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Genetic Engineering Of Plants

  Today it is possible to directly alter the genes of organisms. Transgenic plants carry a foreign gene that has been introducted other into their cells so that they have new and different traits.        Cotton, corn, potato and soybean plants have been engineered to be resistant to either insect perdition or herbicides that are judged to be environmentally safe. Some corn and cotton plants have been produced that are both insect and herbicides resistant. In 1999, transgenic crops were 'planted on more than...

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Salt - Drought and Cold Tolerant Crops

The next step to solve this problem is to produce salt-tolerant crops. It is believed that the prodcution not only of salt but also drought and cold tolerant crops will reduce the need for added farm acreage by increasing agriculturl yields that will provide ... nough for a world population that is expected to nearly double ....2050Increasing The Food Quality Of Crops:         Some progress has also been made to increase the food Auality of crops. Soybeans have been developed that mainly produce the monounsaturated...

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Increasing Productivity

Genetic Engineering is also expected to increase productivity. For this purpose, stromata might be alterned to boost carbon dioxide intake or cut down on water loss. The efficiency of the enzymes RuBP carboxylase which captures Co2 in plants could be improved. A team of Japanese scientists is working in introducing the C4 photosynthetic cycle into rice. Unlike C3 plants. C4 plants do well in hot dry weather. These modifications would require a more complete enigneering of plant cells than the single gene transfers that have been done so...

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Hybridization - Short Note

Hybridization is the crossing of different varieties of plants or even species. It was used to produce plants with desirable traits. Hybridization, followed by vegetative propagation of the mature plants, generated a large number of identical plants with these trai...

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Production Of Salt Tolerant Plant

Production of salt tolerant plant has been a dream of genetic engineer. Recently salt - tolerant Arabidopsis has been produced. For this scientists first identified a gene coding for a channal proteins that transports Na+ along with +H across a vacuole membrane. Isolating Na+ in a vacuole prevents it from interfering with plant metabolism. Then the scientist cloned the gene and used K to genetically engineer plants that overproduce the channel protein. The modified plants thrived (increased) when watered with a salty solution. Irrigation,...

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Marriage to Khadija - Life in Makkah

At that time lived in Makkah, a wealthy and respectable widow, Khadija, daughter of Khuwalid, who was the great grandson of Qussai. She was very impressed by the honesty and goodness of Hazrat Muhammad (P.B.U.H). She was forty years old and twice widowed. She had two sons and a daughter from her previous marriages. On account of her exceptional character, she was known as Tahira, the pious one.  She requested Hazrat Muhammad (P.B.U.H) to take her merchandise to Syria against a share in the profits. She also sent her slave Maisara with...

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Desert Ecosystem In Pakistan

 In Pakistan the desert ecosystems are found in western Punjab (Mianwali and Bukhar) where it is known as "Thai". In southern Punjab Pur (Cholistan), Khan Pur and Rahim Yar Khan also have deserts.       In Sindh this desert ecosystem is called "Thar". These biomes are found on every continent often around 20 to 30 north and south latitude and also in the rain shadows of major mountain ranges. Desert includes a variety of environment. At one extreme are certain areas of the Sahara or Chile, where it virtually never rains...

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Torque & Moment Arm

Torque:  The turning effect of a force about a certain point is called torque. Torque is the resultant of cross product between position vector of the point of application of the force and the force. It is a vector quantity. In SI units, the unit of torque is N-m. Conventionally clockwise torque is taken as negative and anti clockwise torque is taken as positive. When direction of both r and F are reversed then torque, does not change. In rotational motion, the torque is equal to...

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Reading Comprehension Exercise (Passage No: 1)

Questions / MCQS 1. Before man invented writingA. Literature was passed on by word of mouth.B. Prayers were considered literature.C. Literature was just singing and dancing.D. There was no literature.2. As for war songs and prayers each generation.A. Added something of its own to the stock.B. Blindly repeated the songs and prayers.C. Composed its own songs and prayers.D. Repeated what has handed down to it.3. The first war-song.A. Was inspired by God.B. Developed spontaneously.C. Was a song traditionally handed down.D. Was composed by leading...

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Reading Comprehension - Passages, Practice For Entrance Exam - ECAT and MCAT

The history of literature really began was the earliest of the arts. Man danced for joy round his primitive camp fire after the defeat and slaughter of his enemy, He yelled and shouted as he danced and gradually the yells and shouts became coherent and caught the measure of the dance and thus the first war song was sung. As the idea of God developed prayers were framed. The songs and prayers became traditional and were repeated from one generation to another, each generation adding something of its own.        As...

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Al-Sadiq and Al-Amin - Life in Makkah

In his early life, the Holy Prophet worked as a shepherd and look care of the family's and neighbour's herds. When he grew up, he started to trade. Unlike other businessmen of the time, he was extremely honest and fair in his dealings. Hazrat Sa'ad, his businessmen partner said: "I was a partner of Muhammad (P.B.U.H) in business. I always found him very honest in his dealings; he never picked quarrels, nor made any false statement" (Allama Shibi Naumani: Sirat-un-Nabi).   His honesty and truthfulness impressed the people to such...

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Mutation

Mutation is any change in the amount, organizations of content of genetic material. Mutation may be obvious and observable by cytological techniques. Some changes in chromosomes are called chromosomal abberrations. They may be invisible when they are in genes. Both types of mutations when passed from adult to the offspring alter the hereditary instructio...

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Harb-Ul-Fijar - Life in Makkah of Hazrat Muhammad (P.B.U.H)

Hazrat Muhammad (P.B.U.H) was about fifteen years old when a sacrilegious war or Harb-ul-Fijar broke out between the Quraish and Hawazin tribes. The war was so called because it was fought during the sacred months when fighting was forbidden.     Hazrat Muhammad (P.B.U.H) accompanied his uncles, but he did not take an active part in the war. He only collected the arrows thrown by the enemy and handed them over to his uncles.      This was a major event in the life of Hazrat Muhammad and one which must have...

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Half-al-Fazul - Life in Makkah of Hazrat Muhammad (P.B.U.H)

As a result of Fijar war thousands of lives were lost. When the leaders of Makkah saw the effects of the war, they formed a league called Half-al-Fazul with the object of maintaining peace in the region; also for suppressing any violence and injustice and for upholding the rights of the weak, the poor and the destitute.    The alliance was called al-Fuzul after three of the main participants each of whom was called al-Fazal. It is also suggested that this alliance was called al_Fazul because it was made for a noble cause: the...

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Excretion In Plants - Support & Movement

Waste products of catabolism are used by green plants in their anabolic process Green plants do not excrete nitrogenous wastes, on the contrary they recycle breakdown products of nitrogen metabolism. Metabolism of plants is mostly carbohydrate based and its end products CO2 and water and far less harmful than the nitrogenous wastes produced by proteins metabolism in animals.          Certain substances which accumlate to levels in excess of plants need, such as water, carbon dioxide, oxygen and certain ions, are...

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Conditions of Arabia at the time of the birth of the Holy Prophet (P.B.U.H)

Conditions of Arabia at the time of the birth of the 'Holy Prophet (P.B.U.H)'            At the time of the Prophet's (P.B.U.H) birth, the world had completely forgotten the message of the creator and was lost in the wilderness of polytheism. Arabia was steeped in the worst form of idolatry. The Ka'abah was full of idols and every household had its own idol. Stones and trees were also worshipped. There was no belief in life after death and no feeling of responsibility for one's actions. There...

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Why hydrophytes do not have cuticle on stem or leaves?

  The plants (such as water lily), which are found in freshwater habitat either partly or completely submerged are termed as hydrophytes. They do not have any difficulty in obtaining water. The stems and leaves of hydrophytes generally lack cuticle. Their stomata are large and present on the upper surfaces of leav...

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Short note on 'Hydrophytes & Halophytes" - Homeostasis

Hydrophytes:     The plants (such as water lily) which are found in fresh water habitat either partly or completely submerged are termed as Hydrophytes. They don't have any difficulty in obtaining water. The stems and leaves of hydrophytes generally lack cuticle. Their stomata are large and present on upper surface of leaves.Halophytes:       The plants growing in salt marshes close to sea are termed as halophytes eg: glasswort and cord grass. They have to absorb water from such a soil which has higher...

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Why Plant cell does not burst even if placed constantly in hypnotic solution?

 If a plant cell is placed in pure water or solution of higher water potential than the solution in its vacuole, the water moves from outside the cell (endosmosis) and ultimately into the vacuole. As a result, the cell swells or becomes turgid such as external solution is called hypotonic . Further allowing the cell into such hypotonic medium does not cause art internal hydrostatic pressure or pressure potential due to which further up take of water in cytoplasm is resisted and finally sto...

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Cytokinesis - In Animal and Plant Cell

Cytokinesis In Animal Cell:          late telophas the astral micro tubules send signals to region of the cell. Where actin and myosin are activated which form contratile ring, followed by cleavage furrow, which deepens towards the centre of the cells dividing the parent cell into two daughter cells.Cytokinesis In Plant Cell:                         At cytokinesis, in plant of contratile ring a membrane structure phragmoplast is formed from vesicles...

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Cytoplasmic Organelles & Membrane System

1- Endoplasmic Reticulum:       The electron microscope reveals a complex network of channels, the endoplasmic reticulum (ER) which extends from plasma membrane to the nuclear membrane. It is an elaborate. tube like system of lipoprotein. There are two types of endoplasmic reticulum: (a) Agranulated or smooth endiplasmic reticulum (SER) and (b) Rough or granulated endoplasmic reticulum (RER). Smooth endoplasmic reticulum is not associated with ribosomes. It is found in steroid producing cells like adipose cells (fat...

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Detail about ' Chromosomes ' - Kinetochore

Chromosomes are present in the nucleus of the cell. Chromosomes are can only be seen when cells are dividing. In nature cell, each chromosome consists of two very thin threads called chromatids.  They share common point of attachment called centromere, a disc shaped protein struture called Kinetochore is present to which spindle fibres attach during cell division. Centromere has functional relation to movement of chromosome. Chromosome is of thin threads called chromonema, at the beginning...

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Secondary growth In Plants - Stems & Roots

Apical or primary growth increases the length of stems and roots. Secondary growth is the increase in diameter of stem and root due to activity of secondary meristem called cambium. Initially the cambium is restricted to a series of small group of cells. The first step in secondary growth involves the linking of these groups to form a ring of cambium, tissue between xylem and phloem. It is achieved by radical cambium, of cambium cells. Cells of cambium ring divide tangentially to form secondary...

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Short note on 'Growth Correlations

The growth of plant organ is related with the growth of other organs which takes place in different directions. This reciprocal relationship is known as correlation.          Apical dominance is most important correlation found in plants. During growth of apical bud growth of lower axillary bud is suppressed when apical bud is removed the growth of axillary bud is initiated. It means active growth of apices control the development of lateral buds. Auxin is responsible for apical dominance and also for inhibiting...

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Symbiosis - Brief Description

Symbiosis:             There is an association between two organisms, which brings benefit to both the organisms. This association is called Symbiosis.Root Nodules:  The legume plants, pea and bean are the hosts to symbiont bacteria, which inhabit roots forming root nodules. The root nodules bacteria fix nitrogen in soil air, converting it into amino acid, which the host uses. In returen, host provides bacteria will food and protection.Mycorrhiza:  Mycorrhiza is an association between the roots...

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The Character Of Happy Life (Summary)

The Character Of Happy Life (Summary)     This is one of the best known poems of sir Henry wot ten. In this poem he describes the life and character of a really happy person. In his open ion, the happy man in the real sense is he who is slave to none. He is free in his thinking and ideas. He keeps his emotions under his control. He has no lush of name or fame. He does not allow any one to flatter him. He keeps his life free from scandals. He prays God for heavenly rewards. His best companions are religious books and true friends....

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Lucy Gray (Summary)

William Words Worth is great writer of romantic age. He is called the poet  nature for he has interpreted nature in almost all his poems.     'Lucy Gray' is closer to the northern ballads. It describes the tragedy of a Little girl Lucy Gray. She lived on a wild plain her parents. Once her mother had gone to the nearby town for some work. Her father asked her to go to the town as he felt the coming night would he stormy night. Being an obedient child, she gladly set out for the town but unfortunately the storm came before...

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Lines From The Deserted Village (Summary)

Oliver Gold Smith is a great poet of his age. He was born in Island. He transferred and Irish to an English setting.    Is this poem the poet remembers his loveliest village, Auburn and the happy days of his youth. He says that his my village was the most beautiful village of the area. It was very fertile land. The villagers, In spite of hard work and hard life were very happy with their simple delights of life. When ever they were free, they engaged many games and usually used to play these games under the shades of trees. They...

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Under The Green Wood Tree (Summary)

William Shakespeare is regarded as the greatest dramatist in English literature. This song is taken from his popular comedy 'As you like it'. The song is sung by lord Amiens in the forest of Arden, living in exile, along with the banished duke.    In this poem the poet presents a contract between city or court life and the life in the forest. He praises the life of forest and says that there is no one hatch conspiracies against them. They have no rivals in the forest. They are enjoying a very peaceful life. They are exchanging...

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The Abbot Of Canterbury (Summary)

This poem is written by an anonymous poet which tells us an interesting story about king John, the cruel king of England and the abbot of Canterbury. Once the conspirators poisoned the ears of king John against the abbot  of Canterbury. They informed him that Abbot had grown very rich and he was gaining popularity among of area. Therefore he decided to kill him. King John called the Abbot in his court and put the charge of treason on him. The Abbot refused the charge of treason but he put him three typical questions and laid the conditions....

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Germination & Types of Germination

Germination is a process in which seed becomes awaken (active) and starts growth and development to form seeding.       Some environmental factors breaks the seed dormancy and it starts to germinat.Types of Germination: Epigeal Germination: (Epi=above, Geo = Earth)                                         It is a kind of germination during which cotyledons are carried above the soil. It is due to rapid growth of hypocotyl,...

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Rudolf Rassendyll - Character of the Novel (The Prisoner Of Zenda)

Rudolf RassendyllIntroduction:   Rudolf Rassendyll the foremost character of the novel, is the best creation of Anthony Hope Hawkins. Anthony has presented him in such way that he has become immortal in the field of English literature. Anthony Hope has stolen all the sincerity, faithfulness and generosity of this earth to create the character of Rassendyll and make his character to all times to come, a dynamic, smart, handsome and bold hero of the novel, who captures the attention of the reader at the very outset. And as the novel...

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Act III Of The Silver Box (Summary)

Author:   John Galsworthy is a well-known novelist and play writer. His work contains a great deal pf criticism of British society, particularly of the values of the well-to-do professional class. As a writer his greatest contribution to the philosophy of his period in his advocacy of solid ism. In plays, short stores as well as novels he has advocated on equitable distribution of wealth. He has great sympathics with the unfortunate, therefore the great novelist Joseph Con red calls him a "Humanitarian Novelist".Summary:  ...

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The World As I See It (Summary)

Author:   Abbe rt Einstein was born in Germany. He is the most famous scientist, mathematician physicist of the current century. He moved to the United States of America and became an American citizen. He contributed a lot to the field of science. His work was mostly based on reasoning and Mathematics. He was the man who put forward the theory of relativity. On account of his achievements in physics, he was awarded the Noble prize for physics in 1941.Summary:    In the essay " The world as i see it" Einstein has...

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Fritz Van Tarlenhein - Character of The Novel (The Prisoner of Zenda)

Fritz Van TarlenheinIntroduction:    Fritz Van Tarlenhein belongs to an aristocratic family of standsan. He is a soldier by profession. He is loyal to king and adept in his field. He has a loving heart which is full of sincerity.Physical appearance:    Fritz is young, handsome and attractive. He has a well-built body and has pleasant manners.As a Friend:     As a friend is very sincere. He appreciates Rudolf Rassendyll as he finds in him an openhearted and sincere man. This feeling soon becomes...

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Colonel Sapt - Character of The Novel (The Prisoner of Zenda)

Colonel SaptIntroduction:   Colonel Sapt an experienced soldier, is an important character of the novel, "The Prisoner of Zenda". He is one of the faithful servants and well-wishes of king Elphberg. He plays a very active part in releasing the king. He is a short-statured, middle age but well-built man.As a monarchist:    Sapt is a monarchist and serves for the cause of king and country with great  devotion. He is a brave and courageous soldier. Being a monarchist he makes hectic and sincere efforts for the...

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Princes Flavia - Character of The Novel (The Prisoner of Zenda)

Princess FlaviaIntroduction:   Princess Flavia is the most important and sensible female character of the novel. 'The Prisoner of Zenda'. She is angel-like and has bewitching beauty. She is cousin of Rudolf Elphberg, the real king of Ruritania and is the next heir to the throne. She is in her teens, but she is so graceful and dignified that she looks every inch a queen. By virtue of her character that she wins the respect of all those who come in contact with her.A Polite and Intelligent girl:    In her personality...

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Madam Antoniette De Mauban - Character of The Novel (The Prisoner of Zenda)

Madam Antoniette de MaubanIntroduction:    Madam De Mauban is a rich window. She has very attractive and charming personality. She is not Ruritanian by birth, but she has came from Dresden. She moves in the fashionable circles of society and therefore very well know and popular among elites. Due to her beauty many people are ambitious to win her heart.An ambitious and shrewd lady:    Madam de Mauban is an ambitious lady. She therefore wants to attain high position in life. She aspires to become queen, therefore...

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Black Michael - Character of The Novel (The Prisoner of Zenda)

Black Michael (Duke of Strelsan)Introduction:      Black Michael is the villain in the noval. 'Prisoner of Zenda'. He is the half brother of the king. Rudolf Elphberg. He is not the legal heir to the  throne, because his mother belonged to low family. Therefore he is always busy to capture the throne. He is called Black Michael because of his black hair. While the king Rassendyll and Elphberg who belong to the royal family have red hair. His character is also black. Therefore, he is properly called Black Michael.A...

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Rudolf Elphberg - Character of The Novel (The Prisoner of Zenda)

Rudolf ElphbergIntroduction:     Rudolf Elphberg is the real king of Ruritania, and is half-brother of Black Michael, who makes him prisoner in the castle of Zenda. He is well-educated and has passed much of his time abroad. He is very fond of wine. When he sees wine before him, forgets every thing. That's why Black Michael succeeds in making him unconscious and then makes him prisoner in the castle. King Elphberg is a young man. He is handsome to look at all and tall and has good looking stature. The distinctive mark...

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Equilibrium - Physcis

Equilibrium:     Shows an iron ring on which two equal forces are acting in opposite directions. Obviously the ring will remain at rest. This shows that both the forces F 1 and F 2 cancel the effect of each other and the ring remains at rest. This is only possible if forces F 1 and F 2 are equal and opposite and acting along the same line. In this case the resultant of these forces is Zero.    In case the two forces acting on the ring were not equal, the ring...

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