Human Male reproductive System

2:03 AM

External Genitalia:
Male reproductive system consists of external genitalia which consist of a pair of testes which lie outside the body, in the sac like scrotum.
Man reproductive organ which is used to transfer the sperms into the female productive tract.


                  The Male Reproductive System

      Component                                           Function

         Testes                                                                                    Produce sperm and male sex steroids
         Epididymes                                                                          Store sperm
         Vasa deferentia                                                                    Conduct semen to urethra
         Sex accessory glands                                                           Produce similar fluid that sperm.
         Urethra                                                                                Conduct sperm to outside
         Penis                                                                                    Organ of copulation
         Scrotum                                                                              Provides proper temperature for testes

Each testis consists of highly complex duct system called seminiferous tubules, in which repeated division by the cells of the germinal epithelium produce spermatogonia.

These increase in size and differentiate into primary spermatocytes which undergo meiotic division to form secondary spermatocytes and spermatids.
Eventually the spermatids differentiate into mature sperms.

              Spermatocytes  ⟶  Spermatids  ⟶  Sperms

Fluid secreted by sertoli cells provides liquid medium , protection and nourishment to sperms while they are in the tubules.

The sperms are then transferred to the main duct of the male reproductive tract, the vas deferens, which forms highly convoluted epididymis.

Discharge Of Sperms:
The sperms then pass through the urogenital duct and are discharged out. 
The male reproductive system consists of two testes that produce sperms, ducts that carry the sperm and various glands. 

Between the seminiferous tubules are interstitial cells which secrete testosterone.

This hormone is essential for the successful of sperms and also control the development of male secondary sexual characteristics during pubert

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What Is Sexual Reproduction, Fertilization, Oviparous

9:20 PM

Asexual method of reproduction is a primitive form of reproduction than the sexual reproduction. Sexual reproduction is leading to production and union of gametes. Meiosis and genetic recombination played a major role in the development of more complex forms of life and types of gametes.

From identical gametes (isogametes) to the heterogametic stage of motile male gametes (Sperms or antherozoid) and no-motile female gametes eggs (ova).

Sexual reproduction has advantage over asexual reproduction.

Male and female differentiation:

  Both in animal and plants, evolution of sexual reproduction also lead to the differentiation of sexes (male and female). Organisms are either having one sex i.e. hermaphrodite or bisexual.

Advance mode of sexual reproduction has uni-sexuality in animals. But in plants bisexuality in general is retained. Despite the bisexuality (tape worm, earthworm etc). The cross fertilization is ensured for maintaining the advantage of genetic recombination


It is the process which leads to union of gametes. Fertilization may occur outside of the body or inside the body of the female.

External Fertilization:

External fertilization occur in aquatic environment where male gametes can swim towards the female gamete in water medium. Development is also external due to the constant stable condition of water (Forg, fish etc).

Internal Fertilization:

In terrestrial condition fertilization is internal. Sperms are lodged into the female body where fertilization occur.


In reptiles and birds, internal fertilization may lead to external development. They lay shelled eggs to protect the developing embryo from harsh terrestrial conditions. Such animals are called oviparous.


In mammals, internal fertilization leads to internal development and development of embryo is accomplished inside the female body, which give birth to young one-such animals are called viviparous.


In some mammals like Duckbill platypus (arachnids), internal fertilization lead to internal development of the young one in a shelled egg and when development completed , shelled egg is laid which hatched the offspring. This is called ova-viviparous condition.

Protective view:

viviparous and ova-viviparous animal provide more protection to their young one during development. Nourishment is provided either through stored food in the egg or through placenta by the mother.

What Is Sexual Reproduction, Fertilization, Oviparous What Is Sexual Reproduction, Fertilization, Oviparous Reviewed by SaQLaiN HaShMi on 9:20 PM Rating: 5


9:40 PM


The word ''pollution'' mean the destruction of the purity of atmosphere. The pollution of atmosphere is not a new problem. In the past, this problem did not pose a threat to the health of the people. But under modern condition of life, this problem has assumed an alarming proportion. Every country of the world is faced with this problem. Even America, Britain and Japan are worried about pollution. They are making serious efforts to overcome it. It has posed a serious threat to the life of living species. Our rivers, seas, land and air have become polluted. The animal and other living species cannot survive in the dirty atmosphere.

''There are many factor which corrupt and pollute the atmosphere.'' 

(i) First is the ''uncontrolled growth of technology and vast industrial production.'' The mills factories and foundries emit smoke, gases and poisonous fumes and in this way corrupt the atmosphere.

(ii) Second, the discharge of the gases and poisonous smoke is infecting rivers, lakes and oceans. The massive use of pesticides corrupt the atmosphere also. Apart from this, the countryside is being effected by the radiation and waste disposal of nuclear power.

(iii) Third, the ever increasing pollution of the world has also contributed to the uncleanliness of the atmosphere.

(iv) The automobile like buses, cars, rickshaws etc emit smoke in large quantity and defile the environment. 

(v) Man has restored to the game of destroying trees, plants and natural sights in order to fulfill his material needs.

Pakistan is an under developed country. It is also faced with the problem of pollution. Pakistan has a high rate of pollution growth. It has spread a network of mills, factories and foundries. Science and technology have occupied the scene. The use of automobiles has multiplied. The land has been turned barren by the use of pesticides. The government of Pakistan is fully aware of the seriousness of this problem. A national pollution ordinance is on the anvil.

Pollution is a serious danger to the health of man, living species, crops and animals. If it is not checked, it would endanger animal and human life. It will cause many ailments to men. This problem has become, more grave for us because we depend too much on waterways. Our crops, our fields and our forests will soon disappear.

Our government should take effective steps to improve the quality of atmosphere. All activities which pollute the atmosphere must be curtailed.
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10:03 PM



T.V is the latest and wonderful invention of science. In the recent past, the dish antenna was used to receiving signals from T.v station. A large concave reflector was used to receive radial waves from outer space or from T.V station. It has now been replaced by the cable. The dish antenna is no longer in use.

The new system of receiving signals from the T.V station is manipulated by the cable companies. The cable companies use very huge and professional antenna with modern and sophisticated mechanism and satellite station to telecast the programs of T.V station. The cable has also added great comfort to the users of cable. The users of internet enjoy all type of programs, when connected with the cable system.

The cable plays an important role in connecting us with other parts of the world within no time. It has turned the entire world into a global village. Now it has become possible for a television viewer to watch and see programs going on at any T.V station. It has become a matter of mood and choice to switch on any channel and watch the T.V program of your liking. This has linked us with the entire world.

The cable has provided us an opportunity to have the latest information of anything within no time. It has become a means to furnish us news about any incident going on in any part of the world.

Let a person commit any crime. It is sure to brief us about it within fraction of a second. Let a person beat his wife. The cable is there to make a record of it. It enters our private and public life. If a government is toppled down in any part of the world, the cable is there to connect us with its minor details. It give us information of the business trends of various things supplied to the market. The communication of news and pictures from one part of the world to the other stir our imagination and we are loaded with a treasure of information within no time. The cable has replaced the newspapers and magazines. The published material which used to furnish us information in the past has been put to the shade.

'' The cable has provided us a rich source of entertainment.''

Now we do not depend on our own songs, films and plays being telecast. We can switch on our T.V and a whole world of entertainment is before us. We may choose the form of entertainment according to our own mood. The cable has bestowed upon us great choice and opportunity to be entertained. There is no limit to it. It has enable us to judge which T.V station is dong better. We are always after the best...A comparative study of different channels-----is there to broaden our vision. The competition among different T.V channels has urged them to prepare better programs for their viewers. The spirit of competition has urged each one of them to strive for the better and excellent.

Now the monopoly of one T.V station on our time on our time and attention is over. Different channels with their colorful programs of entertainment and information may catch our attention. Our own T.V channel can only survive if it competes with other T.V channels.

'' The cable has entered all fields of our life with its rapid means of information and entertainment.''

Our education, travel, industry and business all depend on it. Its influence on our social, cultural and economic life cannot be set aside by any other means of information. Worldwide information and entertainment at one time is not possible by any other scientific discovery.


However the cable has its negative points also,

  • The use of internet, and T.V viewing can open the doors to a complex kind of cultural invasion.
  • The roots of our own culture are likely to be eroded.
  • The various forms of songs, dances, forms of worship, celebration of event may upset our mind and confuse us.
  • Morals can be affected badly.


Election In Pakistan

5:40 AM


Election are very important for a democratic country. The concept of democracy is linked with elections. Elections are the means to elect the result of the country. The system to elect the rulers by the exercise of the will of the people is very old. It take back to the ancient Greece and Rome. Later on, the system was adopted in a different way by the Muslim Caliph. In the modern age, the rulers of a democratic country are chosen by mean of casting votes. The votes are cast to elect the representative of the people. 

'' The arrangement done to cast the votes is called election.'' 

Election in Pakistan are held to elect the representatives of provincial Assemblies, National Assembly and the Senate. The four provinces have their provincial assemblies. There is party system in Pakistan. The party who returns majority of the representatives forms the government. In the same manner, the party who is in majority at the federal level forms central Govt. The election to senate is based on the equal number of seats, in each province. The senate is the upper house in Pakistan. There are elections to local bodies also. They are also conducted on the above mention pattern.

The elections are conducted and arranged by an election commission. The election commissioner often belongs to judiciary. He is said to be an impartial and fair person. The election commissioner seeks the help of different departments to conduct the election. The judiciary and army are there to help the election commission for a smooth and fair election. The school and college teachers, the bankers and other public servants practically conduct the election.

''They conduct polling on the election day.''

Election comping starts with the announcement of election programmer. Every village, town and city of the country bustles with activity. All the contesting parties, their workers and supporters become busy like a bee. They start canvassing. The banners, posters, portraits in support of the candidate are displayed. Rallies and processions are taken out. Workers and supporters wear badges on their bodies. Slogans are raised in support of their candidates. Fiery speeches are made. The whole atmosphere is charged with tension. The acts of violence are committed. The political animosity reaches its climax. At some places, murders are committed.

Polling day becomes the center of activity. Media men visit different polling stations and keep the people aware of the on going process of polling. Voters rush to the polling station. The workers and supporters of each candidate knock at the door of the people and persuade everyone to cast vote in favor of their candidates. The voters are offered vehicles to reach the polling station. They are served with soft drink and other tasty eatables.

The supporters of each candidate remain at the polling station till the end of elections. They raise slogans and make signs of victory in favor of their country. After the results, the supporters of winnings party fire crackers and beat drums. They go to their candidate in the form of procession, raising slogans in his favor. Election system in Pakistan is not without its faults. After the election, the losing parties claim that the elections were rigged. They are not willing to accept their defeat. But on the whole, elections are tree, fair and impartial.
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Well Come Back

11:24 PM




Well Come Back Well Come Back Reviewed by SaQLaiN HaShMi on 11:24 PM Rating: 5

Psychologists At Work In Various Field

9:11 PM


Psychology is made up of many sub fields, each with its own subject matter, theories and methods. We will discuss sub fields of psychology and psychologists at work in various field.
Many people mistakenly believe that almost psychologists analyze and treat abnormal behavior . However, the range and scope of psychology is much broader than its common misconception would suggest. We can examine the major branches and specialty areas of psychology as applied in today,s world. Psychologists working in various field are:

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What is Psychology

8:43 PM

Psychology is the scientific study of behavior. It is not only to understand people but has also great practical implication for society. It includes not just what people do but also their thoughts, feelings, perception, memories, reasoning processes, and even in one sense, the biological activities that keep their bodies functioning.
When psychologists speak of "studying" behavior, their interests are equally broad. It is not enough simply to describe behavior. As with another science--and psychologists clearly consider their discipline a science--psychology attempts to explain, direct, modify, and ultimately improve the lives of the people and the world in which they live.
Psychologists seek to achieve these goals through scientific methods. They do not consider it sufficient to rely on insight, intuition, and logic to study behavior, too often, people are simply wrong their guesses about human behavior (Kuhn, 1990).
By using scientific procedures, psychologists are able to fine answers to questions about the nature of human behavior that are far more valid than that what mere intuition and guesses provide. And what a variety and range of questions psychologists pose.


  • How do we see colors?
  • What is intelligence    ?       
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Traffic Problem in a Big City and How We Control Traffic

2:45 AM


Life in a big city now-a-days has become very difficult and complicated. A big city offers us many social, economic and political problems which make our life very hard and tough. The first problem which we come across in a big city is uncontrolled growth of population. This has generated the traffic problem. The traffic problem in a big city has gone beyond proportion. The traffic jams in a big city are a daily occurrence.

    .Traffic jams make the march of life slow and unsteady. 

Men and women going to their place of work are at once halted. They do not reach their office in time. The children are delayed to reach the school. The patients do not get medical aid in time. They have to stop on the way. Sometimes, the traffic is jammed for hours together. The small babies in the laps of their mother cry for milk, but they do not get it.
The traffic jams also leave psychological effect on our mind. The passengers delayed due to traffic jams feel frustrated and angry. They blow out their horns out of frustration. The sense of loss continuously hangs heavy on their head. They delayed performance of work or duty may bring to them untold misery or loss.
Traffic jams is the modern age reflect an ugly mark on the beautiful face of the city. They are the negation of progress. In this age of science and technology, such jams cannot be favorable by anybody. They are a denial to the culture growth of a city.
"Lets us find out the reasons for the creation of traffic jams in a big city"

The first reason, of the creation of traffic jams is the unchecked growth of population. The population in a big city is increasing very rapidly. People from village come to settle in the cities. Our villages do not offer them the facilities and comforts of daily life. They come to the big cities in search of jobs and modern facilities of life. This thing has increased the bulk of traffic on the road.

The second reason, the roads of the cities are narrow and uneven. They are not in a good position. They cannot withstand the pressure of traffic. As a result of the traffic jams, the flow of traffic is halted.

The third reason the traffic is controlled and put under heavy control when a V.I.P or President or prime Minister comes to the city. The road is fully banned for the flow of traffic from where the V.I.P has to pass. Another route is re-directed for traffic. The heavy flow of traffic creates jams.

Fourthly, the slow vehicles marching ahead of motorcars sometime put up resistance in the smooth flow of traffic.

                                           MEASURE TO CONTROL TRAFFIC

We can control the traffic jams by adopting the following measures:

  • The rapid increase of population should be stopped by taking different steps. The villages should be urbanized. The migration of the villagers to the cities should be discouraged.
  • The traffic police must be made alert and vigilant.
  • The roads should be widened and put in a good shape.
  • Some roads should not be reserved for the V.I.P,s. They should visit big cities as an ordinary citizen.
Traffic Problem in a Big City and How We Control Traffic Traffic Problem in a Big City and How We Control Traffic Reviewed by SaQLaiN HaShMi on 2:45 AM Rating: 5

The Modern Periodic Table

12:19 AM

If elements are arranged according to their ascending order of atomic number, their chemical properties repeat in periodic manner❞.
In order to make the periodic table more useful and accrue, a few improvements were made by Mosley in the Mendeleev,s periodic table.


(1) After the discovery of x-rays, Mosley in (1931) discovered the atomic number of elements. "Atomic number is the number of protons present in the nucleus of an atom"
According to Mosley, atomic number is the fundamental property of an element while atomic masses  is not is not a fundamental property, as one element has different atomic masses for different isotopes. Hence periodic table was rearranged according to ascending order of  atomic numbers. This improvement which was made by Mosley, was called modern periodic law. According to modern periodic law:
❝ If elements are arranged in the ascending order of their atomic numbers , their chemical properties repeat in a periodic manner.❞

(2) An other improvement was the addition of an extra group (group VIII) at the extreme right of the Periodic Table. This group contains noble gases, which had not been discovered in Mendeleev,s time.

(3) An other confusion in Mendeleev,s table was that elements like Be, Mg, Ca, Sr, Ba, Zn, Cd, and Hg were placed in one vertical group, while according to their properties , they belonged to two different categories. The same was true for so many other elements placed in the same vertical group. In modern Periodic Table, the confusion was removed by introducing two types of vertical groups, A and B. In modern periodic table Be, Mg, Ca, Sr and Ba are placed in group IIA and Zn, Cd, Hg in group IIB.

(4) Position of isotopes was adjusted because the periodic table was based on atomic number.

(5) Position of Lanthanides and actinides was also adjusted.
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Dimitrie Mendeleev,s Periodic Table

10:11 PM


In 1871, a Russian chemist, Dimitrie Mendeleev gave a more useful and comprehensive scheme of the classification of elements. First of all he arranged the elements into periods and groups. Vertical column are called group and horizontal rows are called periods. Mendeleev,s periodic table consist of eight(8) groups and twelve(12) periods. He arranged the elements according to their ascending atomic masses and studies their behavior.
If elements are arranged according to their ascending atomic masses, he found that elements with similar chemical properties appeared at regular intervals.❞
❝The appearance of properties of elements after regular intervals is called periodic law or periodicity❞


 Mendeleev left some gaps in his table for elements, which had not yet been discoverer, and by considering their positions in the Periodic Table he predicted properties of these elements. For example, germanium was not known at that time but Mendeleev was confident that this element must exists so he predicted   its properties. A few years later, germanium was discovered its properties were same as predicted by Mendeleev.
Mendeleev corrected the atomic mass of Be. It was though to be 13.5 which was wrong. He proposed the atomic mass of Be to be 9.


(i) The basis of Mendeleev,s periodic table was atomic mass. It did not give the idea of structure of atom.
(ii) Position of hydrogen could not be deceived by Mendeleev.
(iii) Lanthanides (85 − 71) and Actinides (90 − 103) were not placed properly.
(iv) Position of isotopes was not indicated.
(v) According to atomic masses, the position of following pair of elements was not regular:

                  Ar           K      Co        Ni         Te           I
                 39.9        39     58.9      58.6      127.6     126.9

Dimitrie Mendeleev,s Periodic Table Dimitrie Mendeleev,s Periodic Table Reviewed by SaQLaiN HaShMi on 10:11 PM Rating: 5
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