The Meselson Stahl Experiment - Biology

The three hypothesis of Dna replication were evaluated by Mathew Meselson and Franklin Stahl of the California Institute of Technology in 1958.

       The grew bacteria in a medium containing heavy isotope of nitrogen, N15 which became incorporated into the bases of the bacterial DNA.

       After several generations, the DNA of these bacteria denser than that of bacteria grown in a medium containing the isotope of nitrogen, N14

        Meselson and Stahl then, tranferred the bacteria from the N15 mediun to the N14 medium and collected the DNA at various intervals.

       They dissolved the DNA in Cesium Chloride and then spunt it at a very high speed in an ultra-centrifuge.

Read More

Biosphere

Biosphere is a thin layer of earth in which all living organism exist. Organisms within the biosphere not only adapt to the environment but also interact to modify and control chemical and physical conditions of the biosphere. An organism lives in a habitat.

     Biosphere is spread out over the surface of planet earth extending about 8/10 kilometers in the upper reaches of atmosphere and also in same distance into the depths of oceans.

     An organism responds to a variety of environment factors, and only when all of them are within the range of tolrance, it can inhabit a location. The actual location of place where an organism lives is called its habitat.

Read More

Migration to Abyssinia

The hardships and suffering of the Muslims increased. The Holy Prophet therefore, gave permission to a group of Muslims to migrate to Abyssinia. Accordingly in the fith year of prophethood, a group of eleven men and four women secretly left Abyssinia. These included Hazrat Usman and his wife Ruqayya, daughter of the Holy Prophet (P.B.U.H). Then followed another group of seventy-nine men and seven women including Hazrat Jafar, son of Abu Talib. 

       Najashi, the Christian king of Abyssinia treated the Muslims with kindness and respect and the Muslims found a safe place to live.

       When the Quraish came to know of this, they sent a deputation with some gifts to the king to request him to hand over the emigrants to them.

'       Najashi was a kind and just man. He said in reply that he could not hand over the Muslims to them until he found out the truth about their religion. He called the Muslims to his court and after hearing the speech of Hazrat Jafar who explained the principles of Islam and what the Holy Prophet (P.B.U.H) had taught them, Najashi refused to send them back.

         It is said that Najashi asked Jafar to recite some ayats from the Holy Quran and Jafar recited a portion of Surah Maryam. After hearing it, Najashi said: "By God this and the Gospel are the lights of one candle".

          Thereafter Najashi returned the gifts brought by the leaders of Makkah. Thus the mission failed and the Quraish returned totally disappointed.

Read More

Preaching By The Holy Prophet (P.B.U.H)

The revelations stopped for some time. The Holy Prophet passed this time in restlessness and anxiety, until one day, he saw angel Jibrael again, in the sky seated on a chair. The Holy Prophet became frightened and rushed home. He asked Khadija to cover him up. She covered him up, after which he received another revelation which said:

     "O thou wrapped up (in a mantle)!

Arise and deliver thy warning!

And thy Lord do thou magnify." (74: 1-3)

    In obedience to the command of Allah, the Holy Prophet invited his friends and relatives to the religion of Islam. He preached to them the Oneness of Allah and warned them of the consequences of following their evil ways. But he did not, at this stage, make any public announcement. He confined his message only to those of his close friends and relatives that he thought would give a favourable response. The first person to believe in him was his wife, Khadija, who accepted his message without any hesitation. This was followed by the acceptance of Islam by ten year old, Ali, son of Abu Talib.

     The first freed slave to accept Islam was Zaid bin Haris. The first person to become a Muslim outside the Prophet's immediate family was his close friend, Hazrat Abu Bakr.

       Within a period of three years, while the Holy Prophet was preaching his message in secret, about forty righteous and God-fearing people accepted Islam. Among them were Usman, Talha, Zubair, Abdur Rehman bin Auf, Sa'ad bin Abi Waqas and Abdullah bin Masud.

         The early converts were the people who had witnessed the prophet's private and public life very closely and had arrived at the conclusion that such a gentle and honest person could not mislead the people.

         The came another revelation that said:

"And admonish thy nearest kinsmen." (26: 214)

         In order to carry out this command, the Holy Prophet invited his relatives to his house and said to them: "Allah has ordered me to call you to Him, so who amongest you will help me in this affair and be my friend, my adviser and may deputy?" No one responded to the message except Ali, who said: "O Prophet of Allah! I shall be your helper. I will fight him who fights you." The people laughed and dispersed making fun of the Holy Prophet.

         Soon afterwards he received another revelation through which the Holy Prophet was give the order to: "Expound openly what thou art commanded, and turn away from those who join false gods with Allah." (15: 94)

Read More

Call to Prophethood - Life of Makkah

With age and growing understanding Hazrat Muhammad became more aware of the corrupt society around him and it disturbed him greatly. He could not believe the polytheistic ideas of the pagans of Makkah and often thought of God of his forefathers, Ibrahim and Ismail. He did not follow any particular method of worship, beacuse he was not aware of any, but he realized that there is a force of truth beyond this world which must have power and control over the whole universe.

    A few years before the conferment of prophethood, he became more and more fond of solitude. He started retiring for days with a supply of dates, oatmeal and water into a cave in a nearby mountain, known as Hira. There he pondered and meditated over the condition of his people. These spells of loneliness and meditation because more frequent as he approached the age of forty.

    One day towards the end of Ramazan, he was at the mount of Hira, when angel Jibrael appeared before him and asked him to read. This was so sudden and unexpected that startled by the strange voice, he answered: " I cannot read ". Then he felt that he was being hugged and squeezed so hard that he thought that he would die of suffocation. He was then released and the request to read was repeated. "I cannot read", said Muhammad (P.B.U.H) again. The angel hugged him and asked him to read. Muhammad (P.B.U.H) was afraid of being squeezed a third time, So he asked: "What shall I read?" The angel the recited the following verses:

Proclaim (or read) in the name of thy Lord and Cherisher,

Who created

Created man, out of a (mere) clot of congealed blood.

Proclaim! And thy Lord is Most Bountiful,

He who taught (the use of) the pen.

Taught man that which he knew not" (96: 1-5)

      Muhammad recited these verses after the angel and the words were imprinted on his mind. This was the first revelation and the beginning of prophethood of Hazrat Muhammad. He was then forty years old.

       Muhammad (P.B.U.H) was greatly shaken by this experience and he ran out of the cave. Suddendly, he heard a voice and raising his head in the sky, he saw the same angel in the form of a man filling the whole horizon and saying: "O Muhammad (P.B.U.H), you are the messenger of Allah and I am Jibrael." Whichever may he looked, he saw the same vision and heard the same voice. He stood there until the angel disappeared.

       After the experience, he came home a bit shaken at his selection for this great and noble mission. He feared the thought of the huge and tremendous task of this mission. He narrated the incident to Hazrat Khadija. She comforted him and assured him that no harm could come to a man of his nature and the Allah would perotect him from all evils. Then she look him to her cousin. Warqa in Naufal, who was a scholarlyn person and had embraced Christianity.

         After hearing what had happened to her husband at the mount of Hira, he said that it was the Angel Jibrael who had always brought revelations to previouse messengers of God. He also informed her that his enemies would turn the new Prophet out of his city.

Read More

Fruit Set & Fruit Ripening

Germinating pollen grain is not only in important structure for safe transfer of gametes and insurance for fertilization but also a rich source of auxis as well as commonly stimulating the tissues of the style and ovary to produce move auxin. This auxin is necessary for fruit set i.e. retention of the ovary, which becomes the fruit after fertilization. Without it abscission of flowers normally occurs, leading to low fruit yields.

Fruit Ripening: 

     After fertilization the ovary and the ripe seeds continue to produce auxins which stimulate fruit development.

       Developing seeds are not only a rich source of auxins and gibberellins but also of cytokinins. These growth substances are mainly associated which development of the embryo and accumulation of food reserves, in the seed and sometimes in the pericarp (Fruit Wall).

Climatric: 

       Fruit ripening is often accompanied by a burst of respiratory activity called climatric. This is associated with ethane production, which helps in ripening of the fruit.

Read More

Fixing of Black Stone (Hajra al-Aswad) - Holy Prophet (P.B.U.H)

 The Ka'abah is situated at the lowest part in the valley of Faran and was always flooded by rain water. The people of Makkah tried various methods to stop this flooding. But all their efforts failed and the building was damaged by floods. They therefore, deciced to rebuild it. The task of rebuilding the Ka'abah was divided among the leading families of Makkah and the work was completed in harmony, without any dispute. But when the time came to place the black stone or Hajr -al- Aswad in its proper place, a dispute arose among the chiefs of Makkah. Everyone wanted the honour of placing the Holy Stone in its proper place. There was fear of bloodshed. But then a proposal came from a wise, old man who said that the first person to enter the Ka'abah the following morning, should decide the issue. His suggestion was accepted by all. 

    Next morning, the first person to enter the Ka'abah was Hazrat Muhammad (P.B.U.H), who at that time was thirty-five years old. The people of Makkah agreed to accept his decision.

      He asked the leaders of the different families of Quraish to hold the four corners of a sheet of cloth which he spread on the ground. Then he placed the Black Stone in the middle of the sheet and asked them to lift it up together. When the sheet reached the proper height, he lifted the Black Stone and laid it in its place with his own hands. Thus, an explosive situtation was resolved peacefully by the wisom and foresight of Hazrat Muhammad (P.B.U.H).

Read More