These slides are prepared for students of BS Social Work. Social Workers come across clients in different age groups and categories. This subject helps them put the client into social, physical, psychological, and emotional perspectives. Dr. Imran A. Sajid Department of Social Work, University of Peshawar, Pakistan

1. Factors Influencing Human Growth
and Development
Dr. Imran A. Sajid

4. HEREDITY
 the passing of traits from parents to the child.
 the transfer of genetically controlled
characteristics from one generation to the next
Also called ‘Nature’

5. What is passed on?
1. Physical characteristics
2. Cognitive characteristics
3. Health characteristics

6. 1. Physical characteristics
 such as
◦ Height, hair colour, eye colour, skin colour etc.

7. 2. Cognitive characteristics
 such as
◦ Intelligence, aptitudes (things that can be done well),
and instinct.

8. 3. Health Characteristics
 Many kinds of health issues are also passed on
from parents to offspring.
 Any hereditary disease or resistance to disease
can be passed on.
 Doctors often ask about any disease a person’s
family has experienced because of the strong
genetic link

9.  Recessive Gene Transmission
 Some genes that cause genetic diseases interact
in a dominant-recessive pattern. I
 n these cases, two copies of the recessive gene
are required for the disease to occur.
 A person who has just one copy of the recessive
gene is termed a carrier, since he or she carries
the gene but is not affected by it. In the illustration
above, the dominant gene is represented in green,
and the recessive in blue.
 For the couple on the left, the father has one copy
of the dominant gene and one copy of the
recessive gene. The mother has two copies of the
dominant gene. Each parent can contribute just
one gene to the child.
 The four children shown on the lower left represent
the probabilities (not the actual children) for the
combinations that can result from their parents.
 The children on the far left received the recessive
gene from their father and the dominant gene from
their mother, and are therefore carriers. For any
child born to these parents, there is a 50 percent
chance that the child will be a carrier. Since none
of the children can inherit two copies of the
recessive gene, none of the children will develop
the disease.
 When both parents are carriers, however, as
shown by the couple on the right, there is a 25
percent chance that any child born has the
disease, a 50 percent chance that a child is a
carrier, and a 25 percent chance that a child does
not have the disease and is not a carrier.
 © Microsoft Corporation. All Rights Reserved.
 Microsoft ® Encarta ® 2009. © 1993-2008 Microsoft Corporation. All rights reserved.

10. GENES:
The Foundation of Heredity
 Hereditary details are contained in the genes
located in every cell of the body.
 There are about 22,000 genes comprising the
‘instruction set’ in each human cell, and they
are arranged on 23 paired chromosomes, a
chemical structure which has a single DNA
molecule running its whole length.

11. Size
 If all of the DNA molecules in your body were
uncoiled and laid end to end, it has been
estimated that they would reach to the moon
and back 6,000 times.
 There are more than 10 million million cells
(37.2 trillion) in your body – if all the oceans in
the world were divided into cups of water, there
are more cells in one body than cups of water.

12. Human variation: Why is everyone
UNIQUE?
 It is random which of the pair of chromosomes (one from the mother,
one from the father) is chosen to be present on its own in the sperm
or egg.
 With twenty-three pairs, this implies 223 or over 8 million different
combinations – each fertile person is capable of producing this
number of different eggs/sperm.
 Theoretically, therefore, there are 65 trillion different possible
fertilised eggs combining one of these from a father and one from a
mother.
 In fact, because this is a simplified account, the number of
possibilities is even larger, and this is why each person has a unique
genetic inheritance.
 The one exception is when an existing fertilised egg splits identically
into two.
 These form identical twins, a feature of approximately one in 270
pregnancies.

13. Genes and Sexual Determination
 Twenty-two of the chromosomal pairs are similar for males
and females.
 Chromosome 23 is an exception, and it controls sex.
 It comes in two forms, labelled X or Y because of their
shape.
 If the fertilised egg has the combination XX, the individual is
female; if it has the pair XY, the individual is male.
 The form of the embryo is initially female for all offspring.
 If the Y chromosome is present, it initiates the production of
testosterone in the womb, and this heavy dose of
testosterone causes the development thereafter of male
characteristics.
 Some diseases are linked specifically to the X or Y
chromosome.

14. HEREDITY AND BEHAVIOUR
1. Family Studies
2. Twin Studies
3. Adoption Studies

15.  In family studies, the focus is on the
investigation of blood relatives to see how
similar they are with respect to some trait (for
example, the occurrence of a mental disorder
such as schizophrenia).

16.  English scientist Sir Francis Galton (1822–
1911), who coined the phrase “nature and
nurture.”
 Galton studied the families of outstanding men
of his day and concluded, like his
cousin Charles Darwin, that mental powers run
in families

17.  Bad Seed Theory of Crime
◦ Criminal behaviour runs in families

18.  Twin studies compare identical twins and
fraternal twins for various similarities in
appearance and behavior to see which
traits/behaviors are affected by genetic
makeup.

19.  For intelligence as assessed by IQ tests, the
correlation, an index of resemblance (0.00
indicates no resemblance and 1.00 indicates
perfect resemblance), is 0.85 for MZ twins and
0.60 for DZ twins for studies throughout the
world of more than 10,000 pairs of twins.

20. Adoption Method
 In some cases when twins have been adopted
into separate families, it is possible to expand
the information and determine which traits are
affected by environment rather than heredity.

21.  A 20-year study begun in the 1970s in the
United States of intelligence of adopted
children and their biological and adoptive
parents showed increasing similarity from
infancy to childhood to adolescence between
the adopted children and their biological
parents but no resemblance between the
adopted children and their adoptive parents.

22. Heredity and Intelligence

23.  A 2003 Twin studies of adult individuals have
found a heritability of IQ between 57% and 73%
[1].
 A 2014-15 Twin Study showed heritability for IQ
as high as 80%[2] and 86%[3].
1. Bouchard, Thomas J., and Matt McGue. "Genetic and environmental influences on
human psychological differences." Developmental Neurobiology 54.1 (2003): 4-45.
2. Plomin, Robert, and Ian J. Deary. "Genetics and intelligence differences: five special
findings." Molecular Psychiatry 20.1 (2015): 98-108.
3. Panizzon, Matthew S., et al. "Genetic and environmental influences on general cognitive
ability: Is g a valid latent construct?." Intelligence 43 (2014): 65-76.
27%
73%
14%
86%

24. Heredity and Emotion
 Empathy is the biggest component of emotional intelligence,
but empathy itself consists of two separate abilities.
Cognitive empathy is the ability to recognize another
person's emotions. Affective empathy is the ability and desire
to respond to another person's emotions with an appropriate
emotion of your own.
 They found that genetic variations accounted for about 10
percent of a person's empathy or lack thereof.

25. Genes and Dishonesty?
 A “twins study” led by Peter J. Loewen, of the
University of Toronto, reveals that attitudes
about everyday dishonest behavior have a
large genetic component.
 According to the researchers, genes are
responsible for 26% of their subjects’ views on
avoiding taxes and 42% of their views on taking
unnecessary sick leave.

26. Genes and Aggression: Pakhtun vs
Chitrali
Chitral, 79.4, 50%
Dir, 80.9, 50%
Mean
DIR,
Pakhtun
Chitral,
Non-Pakhtun
Inzimam. (2018). Association between Ethnicity and Aggression: A Comparative Study

27. Aggression and Tolerance amongst
Pakhtun and Chitrali
Chitral Dir
Aggression 58.84 59.8
Tolerance 79.4 80.9
Aggression, 58.84 Aggression, 59.8
Tolerance, 79.4 Tolerance, 80.9
10
20
30
40
50
60
70
80
90

29. IMPLICATIONS FOR SOCIAL
WORKERS
 The client’s family history is necessary in
determining the cause of a problem the client is
currently facing.
 In order to put the client’s behaviour in context,
family history is necessary.
 For social workers working in criminal/juvenile
justice, knowing family crime history helps
understand the client.

30. Do not forget the
Power of Environment/
Socialization/ Nurture/
Learning

31. REFERENCES
 Robert Plomin, Behaviour genetics, in Britannicca
Encylopedia,
https://www.britannica.com/science/behaviour-genetics
 Heredity, in Cliffnotes, https://www.cliffsnotes.com/study-
guides/psychology/psychology/psychology-biological-
bases-of-behavior/heredity
 Minda Zetlin, Do you have Emotional Intelligence? It
could be in your genes. https://www.inc.com/minda-
zetlin/emotional-intelligence-is-partly-genetic-new-
research-shows.html
 The Lying Gene, Haward Business Review,
https://hbr.org/2014/03/the-lying-gene

32. The nature/nurture debate
 Much research has been devoted to
understanding the relative influence of genes
and environment
 in shaping us. Eye colour is determined by
genes; which language I speak is totally
determined by
 experience; a human’s ability to use language
is determined by genes.

33. Environment and Behaviour

34. Maze: puzzle made of connecting parts.
Tolman’s
Maze
Experiment

35.  Rats: one maze trial/day
 One group found food
every time (red line)
 Second group never
found food (blue line)
 Third group found food on
Day 11 (green line)
◦ Sudden change, day 12
 Learning isn’t the same
as performance

36. Edward L. Thorndike’s Law of Effect
 This law states that behaviors
that are followed by pleasant
consequences will be
strengthened, and will be
more likely to occur in the
future.
 Conversely, behaviors that
are followed by unpleasant
consequences will be
weakened, and will be less
likely to be repeated in the
Thorndike’s Puzzle box
Lab Experiment

37. CULTURE AND BEHAVIOUR
 What do you do with the deceased persons?

38. In Tibet, Sky Burial is performed where the body
is chopped, mixed with flour and left to be eaten
up by scavenging bird

39. Yanomomi of Brazil mix the ashes of the corps
with fermented Banana. The mixture is consumed
by all the tribes people.

40. Culture and Aggression:
 Do you think people living in Jungle
environment will be aggressive?

41. Yanomomi Tribe of Brazil thinks
Aggression is Natural
 Living in Forests of Brazil and heavily nature dependent

42. Semai of Malaysia live quite
peacefully.
 Living in Forests of Malaysia and heavily nature
dependent• Culture shapes human nature.

43. Culture and Eating patterns:
What does a mouse mean to you?

44. Roasted Mouse in Hai Duong, Vietnam
 To the people of Hai
Duong in Vietnam,
Field Mouse means
Rich Food Diet
 The field mouse meat
is white and sweet-
smelling just like
chicken.
http://hoanganhship.com.vn/index.php?language=en&nv=news&op=print/NEWS/The-roasted-field-mouse-the-feature-of-special-culinary-culture-31
Cultural Shock

45. Cultural Shock

46. Feeding Dog, Philippine
Cultural Shock

47. Raosted Dogs, Hanoi, Vietnam, and
parts of ChinaCultural Shock
Cultural Shock is Personal
disorientation when experiencing an
unfamiliar way of life.

48. Implications for Social Workers
 Environmental Influences
◦ family composition
◦ family position in society
◦ family socioeconomic status
◦ knowledge of the family
◦ availability of healthy diets
◦ Housing
◦ diseases present in family and child

49.  Cultural Influences
◦ Must be considered when assessing growth and
development
◦ Customs vs. work demands from different cultures

50.  Nutritional Influences
◦ Begins during the prenatal period
◦ LBW/preterm can result from poor prenatal nutrition
◦ Socio-economics may impact growth
 Health Status of the Child
◦ Certain diseases may affect growth & development
◦ Endocrine and cardiac status included here

51.  Family / Parental Attitudes / Child-rearing
Philosophy
◦ Critical in growth and development, esp. emotional
growth
◦ Intellectual growth must be included here as well
◦ Chronic illness can be combated with a loving
environment and close family relationships