Something about the Biological and Psychological bases of human behaviour. Nervous system and endocrine system play the most vital role in behaviour formation.

2. Biological Bases of Behaviour.
 1. Human Anatomy and physiology- Brief
 2. Biosocial Aspects
 3. The Evolutionary Perspective
 4. Genes and Behaviour
 5. Receptor-effector-connector mechanisms-
the Neural Bases of behaviour.
 6. Endocrine System and Behaviour
2

3. • The nature of psychology is bio-social.
• It thrusts upon the behavioral events of
human beings.
• MAN CONSTANTLY INTERACTS
WITH THE ENVIRONMENT
Biosocial
3

4. • Man consistently engages in interaction with
the environment.
• Sensory nerve impulses are transducted to
the brain
• Brain sends motor impulses to the organs of
response.
• The effector organs produce a response
which is called behaviuor.
• This brain mediated receptor effector
mechanisms which produce a behaviour is
called physiological or biological basis of
behaviour 4

5. • BILOGICAL BASES OF BEHAVIOUR
Evolutionary process
Genetics
Neural bases
5

6. Evolutionary Perspective
• Human beings (Homo sapiens) are the most
developed species among the millions of
organisms on earth.
• Organisms show variations among themselves
and others.
• These variations are the main cause Evolution
• Evolution refers to gradual and orderly biological
changes that results in species from the
preexisting forms in response to the changing
adaptational demands of the environment.
• EVOLUTION 6

7. Comparison of evolutionary change in human
brain
7
The largest brains are those of sperm whales, weighing about 8 kg (18 lb).
An elephant's brain weighs just over 5 kg (11 lb), a bottlenose dolphin's 1.5 to 1.7
kg (3.3 to 3.7 lb), whereas a human brain is around 1.3 to 1.5 kg (2.9 to 3.3 lb)

8. Evolutionary Perspective
Evolution follows natural selection.
Natural selection leads to survival of the
fittest.
Fitness refers to the ability of the
organism to survive and contribute its
genes to the next generation
8

9. EVOLUTIONARY PERSPECTIVE
Landmark features in the evolutionary history
of Man
•Bipedalism
•Encephalization
•Language
development
9

10. Bipedalism
• Ability to walk upright on two legs.
• Hands became free to operate tools and
explore the environment.
• Human beings became better adapted to the
environment.
Movie-1
10

11. Encephalization
• Refers to evolutionary change in structure
and size of brain
• Weight of human brain is 2.3% of the body
weight.(1.3 TO 1.4 Kg)
• Due to this specialized brain tissue human
beings became capable of complex activities.
11

12. Language development
• Language made human interactions much
more effective than any other animal.
• Lead to cultural evolution.
• Tool and medium for effective communication
• Through the biological process of evolution human
beings stand at the top of the evolutionary ladder
• Evolution is a continuous process
lang
uage12

13. ENVIROMENTAL INFLUENCE ON EVOLUTIONARY
TRENDS
• There used to gender
based division of labor
in the early human
society
• Now the gender based
differentiation in
human society is
deteriorating day by day
as part of the survival of
the fittest
13

14. Sex determination
• Sex determination is based on the ‘x’ or ‘Y’ sex
chromosomes present in the sperm
• The ovum contains two ‘X’ chromosomes as
the sex chromosomes.
• Sex of the child entirely depend on the
chromosome of the sperm cell.
14

15. GENES AND BEHAVOIUR
• The development of human
being…. Is the climax of all
wonders -Conkun EG
• Human beings with all these
potentials have developed
from tiny threads of life
called Chromosomes
• Gametic cells unite to form
Zygote which contains 23
pairs of chromosomes
Human Chromosomes
15

16. Chromosomes
• Chromosomes contain
DNA in them.
• James Watson Francis
crick, and Maurice
Wilkins studied
extensively on DNA.
• DNAs contain Genes
which are the bearers
of Heredity
James Watson
Francis Crick
Maurice Wilkins
16

17. • Genes are also called
the “master code”
• They contain the blue
print of life.
• Sometimes there will be
abnormalities in the
number of
Chromosomes leading
to syndromes.
Down’s
Syndrome
Klinefelter’s
Syndrome
17

18. • During gamete formation meiotic division
occurs.
• During this process there is exchange genetic
material.
• In the Zygote the genes function in a chance
selection method leading to Character
difference in offsprings.
18

19. Genotype and Phenotype
• The genetic make up of an organism is called
‘genotype’.
• The observable characteristics of an organism
is called ‘phenotype’.
• The given gene can exist in several different
forms
• Change of gene from one form to another
form also can occur ,called mutation.
• Mutation also leads to variation and at last
speciation Movie 1 19

20. The science that focuses on the genetic bases of
behavioral traits such as intelligence, mental
disorders etc .is called
Behavioral Genetics
20

21. NATURE AND NURTURE
CONTRAVERSY
• Despite similarities in
inheritance ,children differ
from their parents in
behavioral and
psychological attributes.
• Heredity (nature) and
environment (nurture)
have significant role to
play in the development
of behavior.
21

22. Socio-biology
• Socio-biology is the systematic study of the
biological basis of social behavior.
• The central assumption of sociobiology is
that the key purpose of human life is to pass
along genes in future generation.
• The evolutionary history evidences the fact
that human beings posses built in
programmed behavioral predispositions. Eg.
Competition, Aggression, Altruism etc.
22

23. INHERITED STRUCTURES
• Under the guidance of heredity, organisms
living in a normal environment, undergoes a
process of growth involving three major sets
of structures .
1. The Nervous system
2. The Endocrine glands
3. The Muscles
First two systems are intensively studied to
understand the Biological bases of behavior
23

24. THE NERVOUS SYSTEM
• Behavior of an organism involves the
coordination of receptors, effectors and
adjustors .
• Nervous system plays the role of the
adjustors.
• So it is important to know nervous system in
detail to understand more clearly about
human behavior.
24

25. THENERVOUSSYSTEM
25

26. 26

27. Nerve Cell
 The basic structural and functional unit of the nervous system is called a
nerve cell or neuron.
 Each nerve cell consists of a central portion containing the nucleus, known
as the cell body, and one or more structures referred to as axons and
dendrites.
 The dendrites are rather short extensions of the cell body and are involved
in the reception of stimuli.
 The axon, by contrast, is usually a single elongated extension; it is
especially important in the transmission of nerve impulses from the region
of the cell body to other cells. 27

28. 28

29. Types of neurons
Sensory or Afferent neuron
Motor or efferent or efferent
neuron
Interneuron or connector neuron
29

30. Monitoring neural
activities
• A specialized cell designed to transmit
information to other nerve cells, muscle, or
gland cells, the neuron is the basic working
unit of the brain.
• The brain is what it is because of the
structural and functional properties of
interconnected neurons.
30

31. • It contains between one billion and one
trillion neurons, depending on the species.
• The neuron consists of a cell body containing
the nucleus, cytoplasm, and an electrically
excitable output fiber, the axon.
• Most axons also give rise to many smaller
branches before ending at nerve terminals.
31

32. • Neurons signal by transmitting
electrical impulses along their axons,
which can range in length from a tiny
fraction of an inch to three or more
feet.
• A neuron is a long cell that has a thick
central area containing the nucleus; it
also has one long process called an
axon and one or more short, bushy
processes called dendrites.
• Dendrites receive impulses from other
neurons.
32

33. • These impulses are propagated
electrically along the cell
membrane to the end of the axon.
• At the tip of the axon the signal is
chemically transmitted to an
adjacent neuron or muscle cell.
33

34. • Two types of phenomena are involved
in processing nerve signals
Electrical and Chemical
• Electrical events propagate a signal
within a neuron, and chemical
processes transmit the signal from one
neuron to another neuron or to a
muscle cell.
34

35. • Like all other cells, neurons contain charged
ions: potassium and sodium (positively
charged) and chlorine (negatively charged).
• Neurons differ from other cells in that they
are able to produce a nerve impulse
• Nerve impulse generation has three stages
• Resting potential
• Generation of action potential
• Propagation of action potential
Sodium Potassium
pump
Action potential
ELECTRICAL TRANSMISSION
35

36. Law governing propagation of action
potential
Propagation of action potential is governed by a law
called ‘All or None law’.
The intensity of the stimulus which is adequate to
produce an impulse is called ‘Threshold stimulus’.
All or none law states that if cell responds it responds
fully provided the stimulus is just above the threshold
value.
36

37. Once a nerve fiber is fired it cannot fire for
a brief period of time – absolute refractory
period (1/1000 sec)
It is followed by a relative refractory period
during which a very strong stimulus is
required to produce a new impulse.
37

38. CHEMICAL TRANSMISSION
• When the electrical signal reaches the tip of
an axon, it stimulates small presynaptic
vesicles in the cell.
• These vesicles contain chemicals called
neurotransmitters, which are released into
the microscopic space between neurons (the
synaptic cleft).
• The neurotransmitters attach to specialized
receptors on the surface of the adjacent
neuron.
Synapse
38

39. • This stimulus causes the adjacent cell to
depolarize and propagate an action
potential of its own.
• The duration of a stimulus from a
neurotransmitter is limited by the
breakdown of the chemicals in the
synaptic cleft and the reuptake by the
neuron that produced them.
39

40. Synapse
40

41. Synaptic facilitation
• Synapse is a case of contiguity without continuity.
In the case of week signals there are two types of
facilitating summation taking place at the synapse.
1) Special summation: Nerve impulses from two
presynaptic neurons combine together
2) Temporal summation: two nerve impulses at some
intervals from same presynaptic neuron combine
within the life period of the weaker signal.
 Excitatory Post Synaptic Potential (EPSP) -
depolarises post synaptic neuron
eg. Acetylecholine
41

42. Synaptic inhibition
• In addition to facilitating functions at synapse
,inhibitory functions also takes place .
• Inhibitory substances hyperpolarize the post
synaptic neuron, making it more negative.
Synaptic conduction
+/-
Inhibition of
neuron Inhibitory Neuron
42

43. Division of nervous
system
1.PERIPHERAL NERVOUS SYSTEM.
2.CENTRAL NERVOUS SYSTEM.
3. AUTONOMIC NERVOUS SYSTEM
43

44. 44

45. Anatomy of PNS
• PNS include cranial and spinal nerves that connect CNS with
receptors and effectors of the body.
• Cranial nerves
12 pairs of cranial nerves arise from brain ( 4 pairs sensory, 4
pairs motor and 4 pairs mixed).
• Spinal nerves
31 pairs of mixed type arise from the spinal cord
Cervical 8 pairs
Thoracic 12 pairs
Lumbar 5 pairs
sacral nerves 5pairs
Cocceageal nerve 1 pair
45

46. Central Nervous System -CNS.
 The Central Nervous System is that
part of the nervous system which lies
within the bony case formed by the
skull and the spine.
 The central nervous system, which
includes the brain and spinal cord,
processes and coordinates all incoming
sensory information and outgoing
motor commands, and it is also the
seat of complex brain functions such as
memory, intelligence, learning, and
emotion.
 The brain and the spinal cord consists
of this system. 46

47. THE SPINAL CORD
 It is that part of the Central neurons
system which lies within the back bone .
 It is composed of the grey matter and the
white matter.
 The grey matter consists of nerve cells
nerve cells lying inside and the white
matter consisting of nerve fibers lying
outside completely covering the grey
matter..
47

48.  Spinal cords function is two fold.
 In the first place it functions as a channel
of communication from the brain and to
the brain. Secondly it works as an organ
for effective reflex action.
Spinal cord cross
section
Spinal cord
48

49. Reflex Action
• Sudden involuntary response to stimulus is
called reflex action
• The stimulus response pass through a ‘reflex
arc’
Reflex
arc
Reflexes
49

50. Reflex arch
• Reflex arch is a simple nervous pathway
connecting a receptor and an effector. It
consists of the following parts
• A) The receptors
• (b) Afferent or sensory neuron
• (c) Association neuron or interneuron
• (d) Efferent or motor neuron
• (e) Effector organ
50

51. Some examples of common
human reflex actions
• (a) Knee jerk reflexes
• (b) Ankle jerk reflexes
• (c) Blinking reflexes
• (d) Sneezing reflexes
• (e) Salivation or watering of mouth on sight,
smell or thought of food.
• (f) Withdrawal reflexes, viz. withdrawal of
hand or finger on touching a hot plate surface
etc. 51

52. Central Nervous System.
• The Central Nervous System is that part of the
nervous system which lies within the bony case
formed by the skull and the spine.
• The central nervous system, which includes the brain
and spinal cord, processes and coordinates all
incoming sensory information and outgoing motor
commands, and it is also the seat of complex brain
functions such as memory, intelligence, learning, and
emotion.
• The brain and the spinal cord consists of this system.
52

53. BRAIN
53

54. Brain
Brain structure
may be divided
into three levels
Brain stem and
Cerebellum
Limbic
system
Cortex
54

55. Brain stem and cerebellum
• Medulla
• Pons
• Cerebellum
55

56. THE MEDULLA OBLONGATA
• The Medulla oblongata is a continuation of
the brain on the one hand and a spinal cord
on the other.
• There fore its nerve tissues form a
connection between the two paths of central
nervous system. It is both a conductor as
well as an integrating center.
• It regulates the highly complex process like
digestion, respiration and circulation which
are necessary for preservation of life.
56

57. Pons
– Provides pathways for sensory and motor
impulses to and from hemispheres.
– It also connects other parts of the brain
with cerebrum and cerebellum
57

58. THE MEDULLA OBLONGATA
58

59. CEREBELLUM
• Cerebellum or
hindbrain is situated
behind and beneath
the cerebrum.
• It helps to maintain
the equilibrium of
the body and keeps
it erect
59

60. Mid brain
• Mid brain connects cerebellum with
cerebrum.
• Connected to the midbrain , there is a
complex mass of network of nerve fibres.
• This is called reticular activating system – RAS
or ascending reticular activating system.
• This is critically concerned with various
degrees of arousal – from deep sleep to alert
awareness
60

61. Reticular formation
The reticular formation is a collection of neurones in
the core of the brain stem, surrounded by neural
pathways that conduct ascending and descending
nerve impulses between the brain and the spinal
cord.
It has a vast number of synaptic links with other parts
of the brain and is therefore constantly receiving
'information' being transmitted in ascending and
descending tracts.

62. Functions
The reticular formation is involved in:
1. coordination of skeletal muscle activity associated
with voluntary motor movement and the
maintenance of balance .
2. Coordination of activity controlled by the autonomic
nervous system, e.g. cardiovascular, respiratory and
gastrointestinal activity selective awareness that
functions through the reticular activating system
(RAS), which selectively blocks or passes sensory
information to the cerebral cortex, e.g. the slight
sound made by a sick child moving in bed may
arouse his mother but the noise

63. • The mid brain is divided into two main parts:
The roof or tectum :
- superior colliculi – vision
- inferior coliiculi - auditory
The floor : provides connection between
lower and higher centres of brain
63

64. 64

65. Fore - brain
• The higher centres of the brain is called fore
brain. It includes :
i. Thalamus
ii. Hypothalamus
iii. Limbic system
iv. Cerebrum
Brain anatomy
Brain basics
65

66. Hypothalamus
66

67. Limbic system
67
The limbic system is a group of brain structures that play a role in emotion,
memory, and motivation. For example, electrical stimulation of the amygdala in
laboratory animals can provoke fear, anger, and aggression. The hypothalamus
regulates hunger, thirst, sleep, body temperature, sexual drive, and other
functions.

68. • The hippocampus is the largest of limbic
structure. It has significant role to play in
memory, particularly in the storage of long-
term information.
• The amygdala has important role to play in
aggression. It is also involved in memory,
emotion, and certain basic motives.
68

69. • The hypothalamus is the smallest structure in
brain with a vital role to play in behaviour.
• It is concerned with regulation of
physiological processes relating to emotional
and motivational behaviours-eating,
drinking, temperature regulation and sexual
arousal.
• It is also concerned with regulation of
endocrine system. Basically, hypothalamus
involves in the maintenance of homeostasis
in the body
69

70. SPECILIZATION OF CEREBRAL
HEMISPHERES
Cerebrum is divided into two equal halves by
a deep grove.
The left hemisphere is responsive to the right
side of the body, while the right side is
responsive to the left side of the body.
Yet the two halves function in unison with
each other with the help of the thick fibres
called Corpus callosum .
70

71. LEFT AND RIGHT HALF OF THE BRAIN
71

72. • Left and Right Brain Functions
Although the cerebrum is
symmetrical in structure, with two
lobes emerging from the brain stem
and matching motor and sensory
areas in each, certain intellectual
functions are restricted to one
hemisphere.
72

73. • A person’s dominant hemisphere is
usually occupied with language and
logical operations, while the other
hemisphere controls emotion and
artistic and spatial skills.
• In nearly all right-handed and many
left-handed people, the left
hemisphere is dominant
73

74. Left hemisphere
Left hemisphere is often called the language
brain.
Stroke on the left side of the brain affects
speech.
SODIUM AMYTAL –a sedative- test on the
brain also indicates the localization of speech
area n the left half.
Left HS is specialized for language function in
95% of the right handed people and 65% in
left handed people 74

75. Left hemisphere
Upper temporal lobes and lower
frontal lobes are main localized
centres for language function
Temporal lobe language centre is
called Wernicke’s area.
The frontal lobe centre is called
Broca’s area.
75

76. • Wernike’s area is mainly involved in
understanding of spoken and written
language.
• Other language problems related to Wernike’s area:
Impaired ability to repeat spoken words.
Reading and writing problem.
Difficulty in naming a common object.
Intrusion of incorrect sounds or words into the flow
of speech.
76

77. • Symptoms of Broca’s area is different from
Wernicke’s area.
• Damage to Broca’s area causes non fluent
and ungrammatical speech.
• Eg. “he go.....school...yesterday...8 o’clock”
(He went to school yesterday at 8 o’clock ).
77

78. Anatomy of language
Wernicke’s Geschwind model
• This model explains how an individual listens,
speaks and understands written words.
W- Wernike’s area
A- Arcuate fasciculus
B- Broca’s area
78

79. • This theory states that each anatomical area
plays a particular role in various aspects of
language.
• Spontaneous speech originates in Wernike’s
area . But to speak it out ,the activity pattern
of the Wernike’s area is sent to Broca’s area
through Arcuate fasciculus.
• The Broca’s area programmes are then sent to
the motor cortex region fore xpression.
79

80. Right hemisphere
Some specialized
centres for language.
Artistic ability
Music
Dance
Imagination
Fantasies
Spatial relation, colour,
size and shape
Creative functions
Emotional expressions
• The right hemisphere is also concerned with the
following aspects:
80

81. Classical method
1. Anatomical method
2. Extirpation and ablation
3. Action potential method
4. Stimulation
5. Chemical method
6. Selective breeding
Modern method
1. C T Scanning
2. PET Scanning
3. MRI Scanning
4. SPECT
5. SCQUID
6. EEG
Methods can be classified into two
headings
METHODS EMPLOYED IN STUDYING BRAIN
FUNCTIONS
81

82. Anatomical method
• Tissue of the
posthumous body is
treated in such a way
that nerve tracks can be
viewed with the help of
a microscope .
82

83. Lesion,extirpation and ablation
• A lesion is the destruction or
functional disruption of an area of
the brain. An ablation is the removal
of a part of the brain. Both of which
produce behavioral deficit indicating
the role of that part of the brain in
developing the lost character.
• Extirpation refers to cutting out.
• A small window on the skull is cut to
remove the brain or part either by
cutting or suction. 83

84. Stereotaxic instruments
• Investigators some times wish to
study the effect of stimulating or
damaging or recording the activity of
deeper part of the brain of animals.
The Stereotaxic instrument is
provided with scale and electrodes.
Researchers refer to a previously
formed map called Stereotaxic atlas
to help this process of study.
84

85. 85

86. Stimulation and recording
from the brain
• In this method electrode are
implanted in the brain and briefly
stimulated certain areas. The
resultant behaviour is studied and
their relation is established between
the stimulated area.
• Eg stimulating the lateral
hypothalamus increases eating 86

87. 87

88. Action potential method
• Sensitive electrical recording devices are used to
detect the electrical changes in the neurons of the
brain.
88

89. Chemical method
• Chemical crystals, drugs or hormones are
inserted to the brain nuclei helps to study the
type of transmitter substances employed in
the synapse
• The resultant reactions are observed to
identify the type of brain chemical involved
89

90. Selective breeding
• In this method the experimenter raises a
number of generation of plants or animals
and systematically sort out each generation
to study the hereditary genesis of behaviour.
• (ie. Transfer of characters/behaviour from
parents to offsprings are studied)
90

91. MODERN TECHNIQUES
• Owing to modern advances in and
developments of modern sophisticated
techniques it is possible to know and
understand the functions of brain without
causing any harm to it .
• These techniques are called Brain Imaging
Techniques (BIT).
91

92. Computerized Axial
Topography(CAT scan
• X- rays are passed
through the brain
at every one
degree of the
brain till 1800
completed.
Computer
reconstructs the
images.
92

93. Magnetic Resonance
Imaging (MRI)
• MRI reveals
structural deficit,
like enlarged
ventricles
93

94. Normal and Schizophrenic Brains(MRI)
94

95. Positron Emission Tomography
• In this method, a patient is injected with
glucose treated with radioactive tracers.
• As the body metabolizes the glucose, the PET
scan monitors the radioactive particles
emitted by the tracers in the glucose.
• Images are produced that show metabolic
reactions, making this method useful to
diagnose brain tumors and
95

96. PETScan
96

97. Single photon emission computed
tomography (SPECT),
• Single photon emission computed
tomography (SPECT), developed in the 1950s
and 1960s, uses radioactive tracers to visualize
the circulation and volume of blood in the
brain.
97

98. Electroencephalography
• Electroencephalography, procedure for obtaining a
record of the electrical activity of the brain by
means of electrodes attached to the surface of the
skull.
Normal Seizure 98

99. THEORIES OF BRAIN FUNCTIONS
• According to this theory each part of the
cerebrum is specialized to perform a particular
function. Eg. Sensory function.
• Three major localized functions are as follows:
I. Sensory functions
II. Motor functions
III. Association functions
99

100. BRAIN AND ITS AREAS

101. Sensory functions
• Most of the sensory functions
have specific areas in the
cerebral cortex called Primary
sensory areas.
101

102. Categorization of sensory function
Sl
NO
Sensory experience
Related sensory
organ
Specified areas in
brain to perform
related function
1 Taste and smell Tongue
Temporal lobe
cortex buried in the
lateral fissures
2 Kinesthetic/somesthetic Skin Parietal lobe
3 Visual Eye Occipital lobe
4 Audition Ear
A portion of
temporal lobe102

103. MOTOR FUNCTIONS
• Primary area- controls some
muscles
• Secondary motor area – less
known function
• Supplementary motor area –
Muscle tone and postural control
Three areas in
the brain has
been identified
for performing
motor
functions.
(Pyramidal
tract)
103

104. Association area
• Learning
• Thinking
• Remembering
• Decision making
• Reasoning
• Motivation
• Emotionally charged activities
• (ie. Higher order brain functions)
Association
area
performs
integrative
functions
104

105. Problems associated with damage to areas
Area Disorder
Frontal lobe Delayed response , blunted expression
Association area Affects learning, thinking, memmory, reasoning, emotionally
charged activities etc
Other defects
Asteriognosis Loss of ability to recognize solid objects through touch
Alexia Inability to recognize printed words
Sensory aphasia Inability to recognize spoken words
105

106. Mass action theory
(Equipotential Theory)
According to this theory different areas or parts of the brain
area are more or less functionally interchangeable.
It has been observed that impairment or injury in a particular
area though cause disturbance or almost complete loss of
function, gradually , owing to practice, the lost function recurs
Also the living structures in the nearby area take over to
discharge the lost function.
106

107. CONCLUSION
• Though the rationale put forward by
equipotential or mass action theorists
are tenable. However modern studies
show that various parts of the brain
are responsible for different functions .
• Therefore a compromising position
appears to be more tenable
107

108. Autonomic Nervous System
• Autonomic Nervous System, in vertebrate
anatomy, one of the two main divisions of
the nervous system, supplying impulses to
the body's heart muscles, smooth
muscles, and glands.
108

109. • Two antagonistic divisions make up the
autonomic nervous system:
1. the sympathetic, or thoracicolumbar, division,
which stimulates the heart, dilates the bronchi,
contracts the arteries, and inhibits the digestive
system, preparing the organism for physical
action.
2.The parasympathetic, or craniosacral, division,
which has the opposite effects, and prepares the
organism for feeding, digestion, and rest
109

110. • The sympathetic division consists of a
chain of interconnected ganglia (groups of
nerve cells) on each side of the vertebral
column, which send nerve fibers to several
large ganglia, such as the coeliac
ganglion.
• They, in turn, give rise to nerves passing
to the internal organs. The ganglia of the
sympathetic chains are connected to the
central nervous system by fine branches
connecting each ganglion with the spinal
cord
110

111. 111

112. • Fibers of the parasympathetic system
arise in the brain and, with the cranial
nerves, especially the vagus and
accessory nerves, pass to ganglia and
plexuses (networks of nerves) within the
various organs.
• The lower part of the body is innervated by
fibers arising from the lowest (sacral)
segment of the spinal cord and passing to
the pelvic ganglion, which gives rise to
nerves for such organs as the rectum,
bladder, and genital organs.
112

113. DUCTLESS GLANDS OR
ENDOCRINE GLANDS
• There are several glands in our body,
which secrete several bodily chemicals
both internally as well as externally.
• They can be grouped into two distinct
categories namely duct glands and
ductless glands or endocrine glands.
113

114. 114

115. 115
Endocrine
system

116. 116

117. 117

118. 118

119. •The under activity or over activity of these
glands caused by the deficiency or excess of the
hormones secreted by them as well as well as by
the co acting influence of other glands like
Thyroid, Pituitary and Adrenal affects not only
the sexual growth and development of an
individual but also his entire behaviour and
developmental process.
119

120. • A slight imbalance of these glands causes
restlessness, anxiety and weakness.
• Our physical strength, morale thinking and
reasoning power and decision-making
ability – all depend upon the health of the
glands.
• In short, these glands are found to play a
dominant role in the life of a person.
• Without their proper functioning a man or
woman finds difficulty in leading a happy
normal life.
120

121. NERVOUS SYSTEM AND
PERSONALITY DEVELOPMENT
• Our behaviour to a great extend is
controlled by our nervous system.
• How we will behave in a particular
situation depends upon the judgment
of our brain.
121

122. 9388200676
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