EDU PSYCHO GURU: ROLE OF HEREDITY AND ENVIRONMENT

ROLE OF HEREDITY AND ENVIRONMENT

HEREDITY

Doughs and Holland [1947] defined heredity in the following words “One heredity consists of all the structures, physical characteristics, functions or capacities derived from parents, other ancestry or species”.

What we get from our ancestral stock through our parents at the time of fertilization of the ovum of mother by the sperm of the father is in the form of chromosomes, genes and their respective classical constituents. The inheritance of traits at the time of conception makes up the native capital and endowment of on individual that are present with him in the form of sum total of the traits basically present in the fertilized ovum. These are called the heredity factors present in an individual.

Role of Heredity in generating individual Differences

Heredity factors begin their influence right from the time of conception of the child through the transmission of chromosomes and genes of its ancestral stock from its immediate parents. The role these factors in providing uniqueness to the personality of the born child and in proving to be a significant factors in generating individual difference can be explained as follows:

1. Heredity determines the sex of the child:-

There exists 23 pairs of chromosomes in the sperm and the ovum .Out of these the first twenty-two pairs of chromosomes are called autosomes. The autosomes are responsible for deciding and determining the growth and development of most of the characteristics and structural composition of our body. The remaining twenty-third pair is the sex chromosome .Whether the baby to be born should be a bay or a girl and what sex-linked characteristics should it possess , are decided by the mechanism of sex chromosomes of the father and the mother . Let us have a deeper understanding of this mechanism.

There are two different types of sex chromosome, X chromosomes (usually big in size) and Y chromosome (comparatively smaller than X). In a male child one member of the sex chromosome is X chromosome (Contributed by the mother) and the other is Y (contributed by the father). In a female child, these sex chromosomes, one from each parent, are X chromosomes.

All eggs have X chromosomes, but sperm cells may contain either type. Therefore, a mother’s role in the determination of her baby’s sex is quite neutral. At the time of conception she can contribute only one type of sex chromosome, I e X-chromosome. Much depends upon the possibility of the type of sex chromosomes X or Y that may be transmitted by the sperm cell of the father. It X chromosome is transmitted, the child will be female and it Y chromosome is transmitted it will result in a male child. Thus, the father is biologically more accountable for determination of the sex of his baby to be.

2. Heredity contributes significantly towards physical constitution.

Most of the attributes related to our body make-up, its constitution and functioning are well decided and guided by heredity, some children have blue eyes, and others have black or brow. Certainly, this difference is actually brought out by their genetic differences; same is the case with the colour and texture of the skin and hair, height, facial outlook and appearances, blood types, finger prints etc…

The son or the daughter of Japanese or a Chinese national can easily be recognized on the basis of physical structure inherited by theme from their parents. An Afghan or a German boy or girl will definitely have well built body structure and tall stature in comparison to an average Indian boy or a girl. This differences is definitely created by means of their respective heredity contributions.

Besides such differences in the physical constitution , structure and body make – up , hereditary factors are also said to be the sole cause for some diseases like tuberculosis , cancer , hemophilia , schizophrenia and other abnormalities .These diseases are result of defect in genes and chromosome and are passed on to subsequent generations.

Along with other necessary physical aspects, the physiological set up of our mind is also well inherited by the child.

The role of heredity as a determinant of physical constitution or bodily make –up become questionable, especially in situations in which the

a. Parents are of black colour while the child is white.

b. Parents are extraordinarily genius while the child is an idiot;

c. Child does not inherit the blindness , lameness or mental disorder of his parents: and

d. Child does not resemble any of his sisters or brothers.

3. Contribution of heredity towards the birth of twins and the related individual.

Sometimes there are births of twins and multiples. Very often they are found to differ much from their siblings in many aspects. Not only are the twins found to differ from their counterparts inspite of their commonness in their heredity stocks, but also they different as individual.

There are two distinctly different types of twins namely identical twins and fraternal twins.

Identical twins: - usually fertilization of one ovum produces one off spring . Sometimes however, when the ovum splits as a result of fertilization the two parts fail to unite together. The result is that each part develops into a complete individual. The twins formed thus are called identical because they carry exactly the same genes. They possess almost the same characteristics and are definitely of the same sex.

Fraternal twins:- Normally, in a woman during each menstrual period , only one ovum is matured but it may happen that two or more ova may mature simultaneously and get fertilized simultaneously by two different sperms . The result is that two different zygotes are produced. The individuals thus produced are known as the fraternal twins or non-identical twins. They have different combination of chromosomes and genes as both ova are fertilized by different sperms. Fraternal twins therefore, are sure to differ in many traits. They need not belong to the same sex.

The above information about twins and multiples helps us draw a conclusion about the role of hereditary factors in bringing individual difference as the following:-

1. Twins are bound to differ from siblings as they are inherited from different sets of chromosomes and genes.

2. Fraternal twins differ from each other on account of the inheritance of different combination of and genes chromosomes.

3. As far as identical twins are concerned, they may exhibit too much of similarities and resemblance on account of their common heredity stocks.

ENVIRONMENT

Meanings and definitions of environment as the following:-

Borning , Langfield and Weld [1961]

“The environment is everything that effects the individual expect his genes”

Woodworth and Marquis [1948]

“Environment covers all the outside factors that have acted on the individual since he began life”

Before birth, the mother’s womb is the place where these forces play their part. The foetus gets its nourishment from the blood stream of its mother. The physiological and psychological states of the mother during pregnancy, her habits and interest, all influence the development of the foetus. After birth, the child is exposed to numerous environmental forces that are purely external. These can be divided in to two parts – physical forces and social or cultural forces. Food, water, climate, physical atmosphere of the home, school, village or city, the natural resources available are included in the physical forces : while the parents , members of the family , friends and classmates , neighbor, teachers , the communication and recreation, religious places, clubs, libraries etc… are included in social forces .

These different environmental forces have a desirable impact on the physical, social, emotional, intellectual, moral and a esthetic development of the individual. Their influence is a continuous one begins with the emergence of life and follows till death.

Role of environment as determinant of individual differences

Hereditary factors are transmitted to the off springs at the time of their conception by the immediate parents, through their respective chromosomes and gene. In this way, actually the role of heredity ends with conception. What goes on inside the womb after conception are thus internal environmental influences. These forces play their role approximately for moths till the birth of the child and are in fact responsible in many ways for shaping the individual. In its true sense they differ not only from mother to mother but also from one child to another of the same mother. Let us now try to understand the influence of internal environment.

A foetus gets its nourishment in the womb indirectly through the mother. Therefore, whatever the mother the mother eats or drinks have an impact on the growth and development of the child. Not only the quality of her diet but also the environment available to her during pregnancy is quite important for the baby. It the mother remains tense, worried, anxious and emotionally aspect or mentally perturbed, then it may eventually have an adverse effect on the growth and development of the baby .

Individual differences in children are e thus certainly caused by the variations and differences existed in the physical and mental health of their mothers during pregnancy. It is said that about Mahabharata you might be knowing Abhimanyu had learnt the art of entering into chakravyuh when he was in his mother’s womb. It may seem an exaggeration but it is certain that what happens with the mother and the child from time of conception till birth is responsible for generating significant individual differences.

At the time of delivery also, the environment available to the mother and the child affects the well –being, growth and development of the child. Here the individual differences may be caused by situations like premature or mature delivery, normal delivery or a caesarean delivery, hygienic or unhygienic conditions, and the general atmosphere at the time of delivery.

After birth , all things related to the external environment – physical , sociological , cultural and psychological influence and affect each and every aspect of the growth and development of the child in every step and at all times , these external environmental influences available to each child are quite different in nature as well as in effect . One may argue that children of the same parents or members of the same family have the same environment. But this never possible, no matter how hard one may try. Even a mother cannot claim playing equal attention, care and affection to all her children. While in most Indian homes male children get preferred treatment over female children, two even real be treated in the same way by their own parents. The same is also true in the case of students being taught by the same set of teachers in the same set-up. No teachers can provide exactly the same treatment to all of his students .Thus as reality speaks, all children cannot be brought up in the same home cannot reside in the same neighborhood, cannot get education in the same institution or get the same social, cultural and psychological set up, hence, individual’s are bound to differ significantly from each other in various ways.

Rincy. B

Social Science