Alhassanain(p) Network for Heritage and Islamic Thought

Evidences for existence of God

Knowing God according to the Holy Quran

The Holy Quran has used many simple and very basic techniques to prove the existence of God; methods, which are nice as well as easy to understand for everyone. This style is not complex and difficult like thereasonings employed by philosophy, that it may not be understood by all. This most simple method does not require prefaces and advanced learning. Every person can benefit from it in accordance with his or her awareness and knowledge. That simple and beautiful method is called as ‘evidence of order’ that awakens the innate natures of seeking God. Therefore study and contemplation on the secrets and peculiarities of the created world is one of the best ways of knowing God.

In a large number of verses, Quran has mentioned examples of the astonishing aspects of universe and wants man to think in the right way and to conclude the existence and being of the Almighty Allah from the order and compatibility. According to Quran, each phenomenon of the world is a divine sign (Ayah). Ayah implies a sign or a mark. If man sees the phenomena of the world as they are, he would begin to believe in existence of their creator; although Quran is not a book of natural science that it may discuss secrets of the phenomena of the world in detail and expose them to man. But it has mentioned in brief their astonishing aspects only to prove the existence of the maker of Universe so that it may awaken the minds of those who have the faculty of thinking; and that it may call their attention so that they may discuss and be curious about the exposition of astonishing secrets of Nature and in this way they may begin to have faith in the creator of the world. In addition to this, they may also benefit to secure the needs of life and inhabit the world.

That is why it can be said that the science of knowing man, knowing animals, knowing plants, knowing lands, knowing space, physics and chemistry are the best ways to know God.

In the Holy Quran, there are numerous verses which mention examples of the astonishing aspects of creation which awaken the nature of man to seek God, so that he may begin to have belief in the existence of a wise and a powerful creator through his conscience. So that he may see the creator of the world with the eyes of his conscience and that he may become attached to Him. These verses can be divided into different groups and each of them talk of one particular aspect:

A) Verses that emphasize contemplation on the creation of man:

The Almighty Allah says in Quran:

فَلْيَنظُرِ الْإِنسَانُ مِمَّ خُلِقَ * خُلِقَ مِن مَّآءٍ دَافِقٍ * يَخْرُجُ مِن بَيْنِ الصُّلْبِ وَ التَّرَآئِبِ

“So let man consider of what he is created: He is created of water pouring forth, Coming from between the back and the ribs.” (86:5-7)

And He says:

وَمِنْ آيَاتِهِ أَنْ خَلَقَكُم مِّن تُرَابٍ ثُمَّ إِذَآ أَنتُم بَشَرٌ تَنتَشِرُونَ * وَمِنْ آيَاتِهِ أَن خَلَقَ لَكُم مِّنْ أَنفُسِكُمْ أَزْوَاجاً لِّتَسْكُنُواْ إِلَيْهَا وَ جَعَلَ بَيْنَكُم مَّوَدَّةً وَرَحْمَةً إِنَّ فِى ذَلِكَ لَآيَاتٍ لِّقَوْمٍ يَتَفَكَّرُونَ

“And one of His signs is that He created you from dust, then lo! you are mortals (who) scatter. And one of His signs is that He created mates for you from yourselves that you may find rest in them, and He put between you love and compassion; most surely there are signs in this for a people who reflect.” (30/20-21)

And He says:

وَمِنْ آيَاتِهِ خَلْقُ السَّمَوَاتِ وَالْأَرْضِ وَاخْتِلاَفُ أَلْسِنَتِكُمْ وَ أَلْوَانِكُمْ إِنَّ فِى ذَلِكَ لَآيَاتٍ لِّلْعَالِمِينَ * وَمِنْ آيَاتِهِ مَنَامُكُم بِالَّيْلِ وَالنَّهَارِ وَابْتِغَآؤُكُم مِّن فَضْلِهِ إِنَّ فِى ذَلِكَ لَآيَاتٍ لِّقَوْمٍ يَسْمَعُونَ

“And one of His signs is the creation of the heavens and the earth and the diversity of your tongues and colors; most surely there are signs in this for the learned. And one of His signs is your sleeping and your seeking of His grace by night and (by) day; most surely there are signs in this for a people who would hear.” (30/22-23)

And He says:

وَاللَّهُ أَخْرَجَكُم مِّن بُطُونِ أُمَّهَتِكُمْ لَا تَعْلَمُونَ شَيْئاً وَجَعَلَ لَكُمُ السَّمْعَ وَالْأَبْصَرَ وَالْأَفْئِدَةَ لَعَلَّكُمْ تَشْكُرُونَ‏

“And Allah has brought you forth from the wombs of your mothers - you did not know anything - and He gave you hearing and sight and hearts that you may give thanks.” (16:78)

And He says:

نَحْنُ خَلَقْنَاكُمْ فَلَوْلَا تُصَدِّقُونَ / أَفَرَءَيْتُم مَّا تُمْنُونَ / أَأَنتُمْ تَخْلُقُونَهُ أَمْ نَحْنُ الْخَالِقُونَ‏

“We have created you, why do you not then assent? Have you considered the seed? Is it you that create it or are We the creators?” (56:57-59)

And He says:

هَلْ أَتَى‏ عَلَى الْإِنسَانِ حِينٌ مِّنَ الدَّهْرِ لَمْ يَكُن شَيْئاً مَذْكُوراً * إِنَّا خَلَقْنَا الْإِنسَانَ مِن نُّطْفَةٍ أَمْشَاجٍ نَّبْتَلِيهِ فَجَعَلْنَاهُ سَمِيعاً بَصِيراً

“There surely came over man a period of time when he was a thing not worth mentioning. Surely We have created man from a small life-germ uniting (itself): We mean to try him, so We have made him hearing, seeing.” (76:1-2)

Points

Important points are mentioned in the above verses for man to contemplate on:

1. Previously man was nothing, except a mixed sperm, which underwent various stages to finally assume the shape of man. This process is worth contemplation and study.

2. Human beings are created in pairs so that they might reproduce and also derive comfort from each other; and God has put love and mercy amongst them, which is one of the divine signs.

3. He created human beings in various colors and races, who speak different languages and this is also a remarkable sign and it is worth contemplation.

4. In the beginning man was not aware of anything and he leant everything from eyes, ears and other senses and conscience. And this too is an astonishing sign worth contemplation and study.

5. Sleep, rest and willingness to obtain livelihood is also a great divine sign.

If man looks at his beautiful structure and ponders well on the extraordinary system and its astonishing aspects, he would conclude that it has not come into being on its own by coincidence. On the contrary it has a wise and a powerful creator.

B) Verses that emphasize contemplation on creation of plants, fruits and human foods:

The Almighty Allah says in the Holy Quran:

وَهُوَ الَّذِى أَنزَلَ مِنَ السَّمَاءِ مَاءً فَأَخْرَجْنَا بِهِ نَبَاتَ كُلِّ شَىْ‏ءٍ فَأَخْرَجْنَا مِنْهُ خَضِراً نُخْرِجُ مِنْهُ حَبّاً متَرَاكِباً وَمِنَ الْنَّخْلِ مِن طَلْعِهَا قِنْوَانٌ دَانِيَةٌ وَجَنَّتٍ مِنْ أَعْنَابٍ وَالزَّيْتُونَ وَالرُّمَّانَ مُشْتَبِهاً وَغَيْرَ مَتَشَبِهٍ انظُرُواْ إِلَى‏ ثَمَرِهِ إِذَا أَثْمَرَ وَيَنْعِهِ إِنَّ فِى ذَ لِكُمْ لَأَيَتٍ لِقَوْمٍ يُؤْمِنُونَ‏

“And He it is Who sends down water from the cloud, then We bring forth with it buds of all (plants), then We bring forth from it green (foliage) from which We produce grain piled up (in the ear); and of the palm-tree, of the sheaths of it, come forth clusters (of dates) within reach, and gardens of grapes and olives and pomegranates, alike and unlike; behold the fruit of it when it yields the fruit and the ripening of it; most surely there are signs in this for a people who believe.” (6:99)

And He says:

وَفِى الْأَرْضِ قِطَعٌ مُّتَجَوِرَ تٌ وَجَنَّتٌ مِّنْ أَعْنَبٍ وَ زَرْعٌ وَ نَخِيلٌ صِنْوَانٌ وَغَيْرُ صِنْوَانٍ يُسْقَى‏ بِمَآءٍ وَ حِدٍ وَ نُفَضِّلُ بَعْضَهَا عَلَى‏ بَعْضٍ فِى الْأُكُلِ إِنَّ فِى ذَ لِكَ لَأَيَتٍ لِّقَوْمٍ يَعْقِلُونَ

“And in the earth there are tracts side by side and gardens of grapes and corn and palm trees having one root and (others) having distinct roots - they are watered with one water, and We make some of them excel others in fruit; most surely there are signs in this for a people who understand.” (13:4)

And He says:

فَلْيَنظُرِ الْإِنسَانُ إِلَى‏ طَعَامِهِ/ أَنَّا صَبَبْنَا الْمَآءَ صَبّاً / ثُمَّ شَقَقْنَا الْأَرْضَ شَقّاً / فَأَنبَتْنَا فِيهَا حَبّاً / وَ عِنَباً وَقَضْباً / وَزَيْتُوناً وَنَخْلاً / وَ حَدَآئِقَ غُلْباً / وَفَاكِهَةً وَأَبّاً / مَّتَاعاً لَّكُمْ وَلِأَنْعَامِكُمْ

“Then let man look to his food, that We pour down the water, pouring (it) down in abundance, then We cleave the earth, cleaving (it) asunder, then We cause to grow therein the grain, and grapes and clover, and the olive and the palm, And thick gardens, And fruits and herbage, a provision for you and for your cattle.” (80:24-32)

And He says:

أَفَرَءَيْتُم مَّا تَحْرُثُونَ / أَأَنتُمْ تَزْرَعُونَهُ أَمْ نَحْنُ الزَّ ارِعُونَ / لَوْ نَشَآءُ لَجَعَلْنَاهُ حُطَاماً فَظَلْتُمْ تَفَكَّهُونَ‏

“Have you considered what you sow? Is it you that cause it to grow, or are We the causers of growth? If We pleased, We should have certainly made it broken down into pieces, then would you begin to lament.” (56:63-65)

And He says:

ألَّذِى جَعَلَ لَكُمُ الْأَرْضَ مَهْداً وَسَلَكَ لَكُمْ فِيهَا سُبُلاً وَأَنزَلَ مِنَ السَّمَآءِ مَآءً فَأَخْرَجْنَا بِهِ أَزْوَاجاً مِّن نَّبَاتٍ شَتَّى‏ / كُلُواْ وَارْعَوْاْ أَنْعَامَكُمْ إِنَّ فِى ذَ لِكَ لَآيَاتٍ لاُِّوْلِى النُّهَى‏

“Who made the earth for you an expanse and made for you therein paths and sent down water from the cloud; then thereby We have brought forth many species of various herbs. Eat and pasture your cattle; most surely there are signs in this for those endowed with understanding.” (20:53-54)

Points

Some very important points are mentioned in the above verses also so that man may ponder over them:

1. Man is in need of different types of foods, and vegetation and plants guarantee this need and produce food for him.

2. Plants depend on water for their own growth, which falls from the sky as rain.

3. Although trees and shrubs grow from the same earth and use the same water, they produce different kinds of fruits and grains.

4. Plants, like animals are also created in pairs.

5. Creation of fruits, grains, vegetables are remarkable and deserve contemplation and attention. In these verses, Quran has called attention to the world of plants and vegetation to highlight astonishing aspects of the plant kingdom so that all may become aware of God creator and that they may benefit from them and their fruits.

C) Verses that emphasize contemplation on the importance of rain and water:

The Almighty Allah says in the Holy Quran:

إِنَّ فِى خَلْقِ الْسَّمَوَ تِ وَالْأَرْضِ وَاخْتِلَفِ اللَّيْلِ وَالنَّهَارِ وَ الْفُلْكِ الّتِى تَجْرِى فِى الْبَحْرِ بِمَا يَنْفَعُ الْنَّاسَ وَمَآ أَنْزَلَ اللَّهُ مِنَ الْسَّمآءِ مِنْ مَّآءٍ فَأَحْيَا بِهِ الْأَرْضَ بَعْدَ مَوْتِهَا وَبَثَّ فِيهَا مِنْ كُلِّ دَآبَّةٍ وَتَصْرِيفِ الْرِّيَحِ وَالْسَّحَابِ الْمُسَخَّرِ بَيْنَ الْسَّمَآءِ وَ الْأَرْضِ لَأَيَتٍ لِّقَوْمٍ يَعْقِلُونَ‏

“Most surely in the creation of the heavens and the earth and the alternation of the night and the day, and the ships that run in the sea with that which profits men, and the water that Allah sends down from the cloud, then gives life with it to the earth after its death and spreads in it all (kinds of) animals, and the changing of the winds and the clouds made subservient between the heaven and the earth, there are signs for a people who understand.” (2:164)

And He says:

أَفَرَاَيْتُمُ الْمَآءَ الَّذِى تَشْرَبُونَ / أَأَنتُمْ أَنزَلُْتمُوهُ مِنَ الْمُزْنِ أَمْ نَحْنُ الْمُنزِلُونَ / لَوْ نَشَآءُ جَعَلْنَاهُ أُجَاجاً فَلَوْلَا تَشْكُرُونَ‏

“Have you considered the water which you drink? Is it you that send it down from the clouds, or are We the senders? If We pleased, We would have made it salty; why do you not then give thanks?” (56:68-70)

And He says:

اللَّهُ الَّذِى خَلَقَ السَّمَوَتِ وَالْأَرْضَ وَأَنزَلَ مِنَ السَّمَآءِ مَآءً فَأَخْرَجَ بِهِ مِنَ الثَّمَرَتِ رِزْقاً لَّكُمْ وَسَخَّرَ لَكُمُ الْفُلْكَ لِتَجْرِىَ فِى الْبَحْرِبِأَمْرِهِ وَسَخَّرَ لَكُمُ الْأَنْهَرَ

“Allah is He Who created the heavens and the earth and sent down water from the clouds, then brought forth with it fruits as a sustenance for you, and He has made the ships subservient to you, that they might run their course in the sea by His command, and He has made the rivers subservient to you.” (14:32)

Points

1. These verses describe the beautiful water cycle in nature. The water in oceans evaporates through heat of sun and appears in the sky in form of clouds; and then through the movement of the winds, is transferred to different parts of the earth, where it falls in form of rain and becomes available for human beings, animals and plants. This is one of the divine signs that He has created such a novel system.

2. Although sea water is saline and bitter, rain water is sweet and potable.

3. Water, which is the nectar of life for plants, animals and human beings; was created as a liquid, so that it may flow in the form of streams to be made available for all and also used as mode of transportation (shipping).

Creation of water and its cycle in nature is one of the amazing signs of His creation and for those who have sense, it is worth contemplation; and the order, coordination and connection between human beings, animals, plants, heat of the sun, wind and earth show that these are the best evidences of the existence of a wise and powerful creator.

Orderliness and coordination in the world

Look at a book; it consists of millions of letters and thousands of words, all of them in a proper arrangement. What is the relation between these letters and words? Are they placed haphazardly besides each other without any system? Or they are arranged in a systematic manner?

After you read the book, you conclude that all the letters, words, sentences and different sections of it are perfectly connected to each other and appropriately placed one after another in order to achieve a single aim. These letters and words are arranged in a particular way and each of them has a peculiarity. You will understand well that an aim was followed in arrangement and compilation of these letters and words. You will also realize that the compiler of the book possessed intellect and understanding and was previously aware of his work and he arranged the letters and words with foresight and aim in this particular way; and that he is an expert of his field. In an organized collection, each of its parts is related to others and follows a single aim. Every part is having a particular position and function, that if it is placed in another place or does not perform its function, its job would remain incomplete and the intended aim would not be realized.

Can you have the feeling that it came into being on its own coincidentally without any aim? Can you imagine that an existing being without sense and perception - for example the wind - has pulled the pen across the paper and this book was produced through this process? You can never imagine that the book came into being automatically without an objective and cannot in any way presume that it came into existence through a thing lacking sense and perception and it coincidentally took the shape of this book. Because you know that every phenomenon has an appropriate cause and if someone was to make such a supposition, you would laugh at him and consider his statement senseless. Therefore the presence of the book and systematic arrangement of its words lead us to conclude the following:

Firstly, that the book is having a writer or a compiler.

Secondly, that the writer is wise, intelligent and expert in his field and that he followed a particular aim in his work.

In the same way, every orderly and aimed mechanism leads you to conclude that it has a wise and an aware maker and as much complex that machine, as much would be the capability of its maker.

The great book of creation is also having letters, words and sentences; every existing thing and phenomenon are words and sentences of this great book. Occurrences and phenomenon of the world are not haphazard and random, on the contrary like letters and words of the book; they have order and coordination throughout. In this great book, you would see that in the structure of human body, which is a book of creation, there are hundreds of systematic and orderly mechanisms and in the structure of each of them you would see precision and accuracy. This system is made up of various organs that work in unison. They cooperate with each other and fulfill the needs of each other. Every system of the human body is like a huge workshop. And all these workshops are connected to each other. All the physical organs of man work in order and coordination, so that man can continue to live.

Human body also is unable to survive all by itself. On the contrary, it depends on various other existing things like water, air and different types of nourishments; trees, plants and animals; and also various natural minerals of the earth. He cannot live without them and he is also dependant on the heat and light of the sun, the orderly movement of the earth and the rotation of the days and night and the different seasons.

So much so, that you would say that all of them shape a single real entity in which perfection, organization and compatibility is maintained. Look at this great book of creation; that is this world, carefully and take note of its searching and beautiful words; you would definitely see coordination and system in them. What do you see? You would well understand that this great creation has not come into being by coincidence and without any objective. Senseless and imperceptive Nature could not have brought into existence such a precise system. It cannot write such a meaningful and aimed book. By looking at the world and by understanding its connection and coordination, you would nicely be able to discover its actual cause. You would conclude the world is a creation of a wise and powerful being, who created it with a particular aim and who is also controlling it. You would see this system everywhere; every phenomenon you study, you will become aware of the knowledge and power of the God, creator of the world. And this way of looking and pondering is the best way to recognize God; and it is called as the evidence of order.

Numerous verses of Quran emphasize contemplation on the creation of the earth and the heavens, sun and stars, animals and plants, systematic appearance of day and night, physical development of man, differences of colors, faces and languages in order to discover the creator of the world.

Water Cycle

Green Leaves

Digestive System

Mechanism of Sight

Circulatory System

Water Cycle

Distribution of water between existing things is very remarkable and amazing. The real sources of water are the seas, oceans and lakes. Water is distributed throughout the earth from these bountiful sources.

Water of oceans, seas and lakes, under the effect of the heat of sun, turns to vapor and rises to the sky. Vapors wander in sky with the movement of winds. When temperature and pressure reach a particular level, they appear in form of clouds and float to various parts of the earth by the movement of fast and slow winds, where they drop as rain, soaking up the earth and giving rise to vegetation and greenery. Rain water then seeps into the earth and is stored in it for needful times. The stored water sometimes erupts from the lap of mountains in form of springs or human beings make efforts to dig wells and gain from the life-giving sources of water in the earth.

Drops of rain, in special circumstances, fall to the ground slowly and beautifully in form of snow. Snow which is very beneficial for vegetation as it turns into water gradually and seeps into the earth and is stored underground or emerges as springs and rivers and becomes available for those who need it and in the end return to the seas.

The quality of the rising of vapor and its being transferred from one place to another by the help of wind itself deserves contemplation. If wind power had not been there, how the clouds would have been distributed in the atmosphere? How they would have traveled here and there? If the heat of the sun had not been there, would the water of the sea have turned into vapor? If the water had only turned into vapor at temperature of a hundred degrees, would it have been sufficient for existing beings? Would human life have been possible in those circumstances? If rain had not fallen down in drops, what difficulties it would have brought? For example, if rain fell from the sky in one place in form of a stream, what would happen? Would it have been able to seep into the earth in a gradual manner and be stored in it?

Quality of rain and snow in purifying the atmosphere is also remarkable and worth pondering. If rain and snow had not absorbed the toxins and dirt of the atmosphere, would you have been able to breathe?

Now you must have noted what valuable qualities are present in water, snow and rain. How the sea and sun, wind and cloud and rain etc. act in a precise coordinated way to provide means of life for us and other existing things.

What does this system and coordination prove? Is it not the best proof that intelligence and determination had a role in the creation of this magnificent world? Does this system and coordination not tell us that a wise and a powerful being has created this world? And that He created man and other existing things and all that they need?

Now, that we have mostly understood well the value, importance and qualities, we must see what the Almighty Allah has fixed as our duty before these bounties. He has commanded us to enjoy the benefits of these bounties and be obedient and thankful to Him. That we drink it and give to others; that we may purify ourselves and our surroundings through it. We should take care that we must not waste it, that we should be thrifty in using water so that others may not have to face its shortage. We must not pollute rivers, streams, seas and sea shores. We should try to save underground water bodies and use this great divine bounty in a nice way, on which human, animal and plant life depends to populate the earth and to guarantee the needs of all.

The Almighty Allah says in the Holy Quran:

وَجَعَلْنَا مِنَ الْمَآءِ كُلَّ شَىْ‏ءٍ حَىٍّ

“…and We have made of water everything living.” (21:30)

And He says:

أللَّهُ الَّذِى يُرْسِلُ الرِّيَاحَ فَتُثِيرُ سَحَاباً فَيَبْسُطُهُ فِى السَّمَآءِ كَيْفَ يَشَآءُ وَيَجْعَلُهُ كِسَفاً فَتَرَى الْوَدْقَ يَخْرُجُ مِنْ خِلاَلِهِ فَإِذَآ أَصَابَ بِهِ مَن يَشَآءُ مِن عِبَادِهِ إِذَا هُمْ يَسْتَبْشِرُونَ

“Allah is He Who sends forth the winds so they raise a cloud, then He spreads it forth in the sky as He pleases, and He breaks it up so that you see the rain coming forth from inside it; then when He causes it to fall upon whom He pleases of His servants, lo! they are joyful.” (30:48)

And He says:

هُوَ الَّذِى أَنزَلَ مِنَ السَّمَآءِ مَآءً لَّكُم مِّنْهُ شَرَابٌ وَمِنْهُ شَجَرٌ فِيهِ تُسِيمُونَ‏ / يُنبِتُ لَكُم بِهِ الزَّرْعَ وَالزَّيْتُونَ وَالنَّخِيلَ وَالْأَعْنَبَ وَمِن كُلِّ الَّثمَرَ تِ إِنَّ فِى ذَ لِكَ لَأَيَةً لِّقَوْمٍ يَتَفَكَّرُونَ

“He it is Who sends down water from the cloud for you; it gives drink, and by it (grow) the trees upon which you pasture. He causes to grow for you thereby herbage, and the olives, and the palm trees, and the grapes, and of all the fruits; most surely there is a sign in this for a people who reflect.” (16:10-11)

Green Leaves

All of us require food and we cannot survive or work without nourishment. Trees and plants prepare food for us. The green leaves of plants are small food-making workshops; they work and produce food for us.

Plants and trees obtain water and minerals from soil through roots and transport them to the leaves through stems.

Carbon dioxide also, which is present in the atmosphere enter the leaves through numerous tiny pores and light and solar energy also heats up the leaves.

At that time, the workshop of green leaves starts working and prepares food with the help of the sun.

Plants produce more food than what is required for their own use; they use some of it and the rest is stored for us.

Sheep and cows also require food and they graze on green grass and feed on grains and produce for us milk, cheese and meat. Fowls also feed on grain and produce eggs and chicken for us.

All animals and beasts are in need of plants and the food of all of them is prepared through green plants. No human being or animal can produce their food without the help of plants. All are in need of plants.

Human beings are in need of plants and animals, and animals require plants and plants require water, soil, carbon dioxide and sunlight to prepare the food.

Now let us see who has created the sun, so that it may shine on the earth and distribute light and energy for the plants to produce food for us. Who has created these systematic and coordinated trees and plants and given to the green leaves the power of producing food?

That wise and powerful being is God, who is all knowing and all powerful.

That wise and powerful creator loves us so much that through foresight He has created everything that we might ever need. We also love Him; we thank Him for His bounties, accept His guidance and follow them - who can guide our life better than Almighty God?

Digestive System

We require food for health, survival, movement and work. Materials required by our body are present in the foods that we eat. But most of them are not absorbed into our body in their original form; on the contrary they have to be digested. Digestion is the process of breaking up the food that we eat into a form that can be absorbed into our body to produce nourishment. And this important function is performed through the digestive system. Digestive system consists of a tube which begins from the mouth and ends at the last outlet (anus). Passing through this small workshop, food undergoeshundred of thousands processes and fine and amazing reactions and becomes digested and absorbable. So many elaborate processes take place, which can hardly be described over here. Some of them are mentioned by way of examples.

We shall divide the digestive tract into parts and explain the function of each part in brief.

Mouth: Some organs are present in the mouth which are effective in digestion: lips, tongue, teeth (in particular way), jaws and three pairs of salivary glands.

When the morsel enters the mouth, the lips close the entrance so that the food may not fall out. The tongue rotates in the mouth and places the morsel under the teeth. The lower jaw moves up and down so that the morsel may be chewed and become soft. All this time, the salivary glands secrete liquids and enzymes on the surface of the morsel so that it may help in digestion. Secretion of salivary glands continues at other times also and keeps the tongue and lips moist to facilitate speaking and breathing and also to help in the sense of taste.

Throat and the process of swallowing: Three passages are present in the gullet, the nasal tube, respiratory tube and the food tract, which is connected to the stomach. Food must not enter the air tube or it would disrupt breathing and we would choke. When the morsel in the mouth is ready to be swallowed, the tongue gathers it and sends it to the throat. At that same time the uvula is raised and closes the nasal tube. The air tube is also closed by the epiglottis. The only thing open at that moment is the food tube and the morsel enters it and by the worm like movements is propelled to the stomach.

Circular muscles in the last part Esophagus (cardia ) is normally contracted and it prevents the stomach juices from entering the esophagus, but on receiving worm-like motions to this end, the contraction of muscles goes away and the entry of food to the stomach is facilitated.

Stomach: The food matter remains in the stomach for a period of time. Different types of foods stay in the stomach for different lengths of time. After the food enters the stomach, weak contractions appear in its muscles. They become stronger and more frequent gradually. These contractions in the form of worm-like waves begin from below (cardia ) and throughout the length of the stomach travel to the pyloric sphincter, and as they reach the pyloric sphincter they become stronger and causing the softening of food matter and its mixing with the gastric juices. There are numerous glands in the inner wall of the stomach that secrete enzymes and special liquids on the surface of the food; with this action starch is converted into glucose and protein is changed to amino acids. Also the food matter is converted into smaller particles fit to be absorbed by the different cells of the body. The food matter through these actions and reactions assumes the form of a paste, which is called as chime and after that it gradually enters the duodenum.

Duodenum: The initial part of the small intestine is called duodenum. When the food enters the small intestine, it first passes through the duodenum and at this place through pancreas and gall bladder liquids are sprayed on its surface, which affect digestion of food in a systematic manner.

Small intestine: The food does not stay in the small duodenum; on the contrary it passes through it into the small intestine. Matter resultant from digestion of food through the small intestine is absorbed and enters the blood stream, so that with the circulation of blood it may come at the disposal of all the cells of the body. The inner surface of the small intestine has numerous folds through which the digested food is absorbed into the blood stream and transferred to the liver.

Large intestine: The large intestine is the last part of the digestive tract. When food enters the large intestine no useful or absorbable matter remains in it. Things that remain behind in it are a quantity of water, salts and a little undigested food matter. The walls of the large intestine absorb the water and salts and in the end, half solid excrement including dead and alive bacteria and indigestible matter remains in the rectum till it is excreted through the anus.