Weighing 3 pounds, a walnut-shaped organ, made of white and grey tissues.
The brain is housed inside the skull. For a man, the brain is supposed to be the most important
organ. Memory, personality, reactions, receiving and transmissions of messages and
issuing of commands to the activities of the body – all these are controlled by the
brain. Forgetfulness and timely recollection is its greatest specialty.
Centers of the systems, such as the digestive system, the respiratory system,
the circulatory system, the glandular system, the excretory system and the nervous
a system is located in the brain.


The brain is divided mainly into three parts; the forebrain, the midbrain and
the hind brain. The fore brain is the largest part and most of its is composed of two
cerebral hemispheres. The right hemisphere is separated from the left by a deep
midline groove which contains the falx-cerebri.
Cerebellum: The left part of the brain controls the right side of the body and
the right side controls the left side. Our body controls several organs as pairs-such
with two adrenal glands, two kidneys, two lungs, two brain hemispheres etc. This part
of the brain helps us mainly in the regulation of speed harmony, movement of the
body and inhalation. In such activities, one does not need to concentrate.
Cerebrum: Cerebrum is composed of both the frontal cerebral hemisphere
and the right cerebral hemisphere. It controls such faculties as consciousness,
emotion, thoughts, and utterance of feelings and the control of our desires. If one part
of the cerebrum is affected, its impact is felt in all other parts accordingly, as its areas
are strongly connected with one another by neurons (nerve cells). If it does not
function properly, other parts are also adversely affected. Cerebrum also governs the
areas of organs of perception or knowledge (“Gyan Indriyas”) and our muscular
movements. The space between the cerebrum and the spine is known as Medulla
Oblongata. Messages are received and transmitted through cerebrum.
Any kind of injury or the formation of a clot is fatal for the brain. They
adversely affect the whole body. The above mentioned facts are quite consistent
with the medical science. But our sages “Rishis” and saints have made far deeper
research into the mechanism of the brain. The enquiry of the mind is far beyond that
of the brain. It is like this.
The mind transits thoughts to the intellect for its approval. After their approval
by the brain, it sends its commands to the sense organs accordingly and the sense
organs in their turn activate the different parts of the body for their compliance.
Let us now consider the functioning of the sense organs. When our eyes
observe and object they pass it on to the mind which in its turn takes orders from the
intellect which in its turn gives order to the feet to move on towards the destination.
Likewise the hands get order to touch an object to know its qualities. The sense of
tongue is ordered by the intellect to feel its quality by virtue of taste. The sense of
hearing, the ear is to understand the quality of an object by virtue of sound. This is
how the different sense organs are pressed into service for the attainment of a single

object. But with what coordination and quickness, the whole process takes place is
difficult to imagine. But after the attainment of the object, one not only experiences a
feeling of joy, but also an experience of contentment in one’s mind, because one
feels, completely satiated after the object is attained. It must be noted here that real
happiness does not lie in the attainment of an object. It lays the renunciation of its


Spine is the expansion of our brain. It is about 45 centimetres long. It consists
of 33 vertebrae, each part connected with the other by means of a joint. These joints
help the spinal cord to absorb shocks. The safety of the spine is ensured by armour
of three layers. Liquid substance keeps flowing through its midst. The spine is not
absolutely straight, but curved at 5 points. This enables us to move in all directions-
left and right, forward and backward.
The uppermost part of the neck………………….7 vertebrae (Cervical)
Below that in the thorax region…………………..12 vertebrae (Thoracic)
Below that in the lumbar region………………….5 vertebrae (Lumbar)
Below the waist in the anal region……2 vertebrae (Sacral and Coccygal) (5+4)
– These are connected with each other.
Thirty one (31) pairs of veins
emanate from these vertebrae. Around
half of these veins send messages to the
brain. The remaining ones transmit
messages from the brain to the muscles.
In moments of mental disturbances and
emotional crisis the muscles remain
extremely tense; otherwise in normal
conditions they remain quite healthy.

The following diagram will clarify the working efficiency of each vertebra of the
spinal cord in different parts of the body :
Certical C Vertebrae of the neck 7
Thoracic T Vertebrae of the year 12
Lumber L Vertebrae of the waist 5
Coccyx O Vertebrae of the Basti area
Coccygal 5 and 4 Combined 1 + 1 = 2 2 26


Vertebra : Physical Region of Spinal Nerves
C-1 Head, Pineal Gland, Skull, Brain, the Facial Bones, Inner section of the Ear,
Sympathetic Nervous system.
C-2 Optic Nerves, Nudotory Nerves, Feeding Nerves, Mastoid, Tongue and
C-3 Cheeks, the outer section of the Ear, Teeth and Trifacial Nerve
C-4 Nose, Lips, Mouth and Eustachian Nerve
C-5 Sound Nerves, Glands of the Neck and Pharyns
C-6 Muscles of the Neck, Shoulders and Tonsils
C-7 Thyroid Gland, Bursa in Shoulder, Arms


T-1 Hand-from the elbows to the fingers, Food pipe, Esophagus and Trachea
T-2 Heart, Heart valve, Coronary Canal
T-3 Bronchial tube, Pleura, the cover circling all the four sides of the Lungs,
Breasts and Chest
T-4 Gall Bladder, Common Duct
T-5 Liver, Solar, Plexus, Blood
T-6 Stomach
T-7 Pancreas…….and Deodenum
Secret of Human Body
T-8 Spleen & Diaphragm
T-9 Adrenal Glands
T-10 Kidneys
T-11 Ureters, Kidneys
T-12 Fallopian Tube & Lymph Circulion


L-1 Large Intestine and Inguins Rings
L-2 Appendix, Abdomen
L-3 Male Organ, Dimba Gland, Uterus, Knees and Bladder
L-4 Prostate Glands, Muscles under the lower part of the Waist
L-5 The under part of the Knees, Ankles, Pawn, The mid-circle under the Feet,
Sciatica Nerve
Sacrum – Buttocks and its bones
Rectum – Kidney and Anus


During the practice of Yoga, we give sometimes a forward movement or a
back movement to the spine & sometimes the movement is given by inhaling and
sometimes by exhaling the breath.
In some Asans (postures) we bend it towards the right and left, while in some
other asans we bend the spine below the middle towards right and above the middle
towards left. In some asans we try to stretch it towards the earth. Sometimes we
keep it parallel to the earth or sometimes in a horizontal way. The different postures

have a salutary effect on the vertebrae of the spine, its mid-joints and the root-
nerves. As a result of it the cerebral column remains strong and elastic.
Not only this, the distribution centres of five Prans, situated on the spinal cord
are deeply influenced by it. Its impact is also felt on the entire body-from the head of
the foot, bones, muscles, blood circulation, nerve-system as well as other systems of
the body. Besides our respiratory system too gets completely overhauled.
All that we have said above is concerned with the physical form of the spine.
But there are such centres and veins in the body that are purely subtle or astral.
They are not visible to the naked eye like veins or arteries. The power of our vital
energy i.e. Pran reaches the different parts of the body through these subtle veins.
Each Chakra stands at each of the five bends of the spine, where also is situated the
confluence of the veins. One can have a clear understanding of these bends of the
spine in the spine diagram given on page 5.
These Chakras (Spiritual Centres) are close to those gross centres that
doctors are familiar with. These subtle centres affect the subtle veins, the subtle
veins the gross centres and the gross centres in turn affect the veins and arteries.
We have explained them in detail in the chapter on Pranayam. By controlling the
body we can control these spiritual centres through there are innumerable such
veins in our body, the number of the main Nadis are there – (1) Ida. (2) Pingla and
(3) Sushumna. They keep the body cool, warm and balanced respectively.
Yoga has the capacity to purify all these Nadis and influence the Sushumana
Nadi that passes through the middle of the spinal cord. It also awakens its dormant


Here we find it necessary to make you familiar with a general knowledge of
the mind. Pran stands between the gross body and the Mind & makes its impact on
both. The difference between the Brain and the Mind is this that while the former is
gross, the Mind is subtle or astral. The brain can be cut opened and operated upon, but
not the Mind. The region where thoughts come and go, where resolutions rise and
fall is called the Mind.
One of the functions of the mind is to help flow the experienced sensations
into the different parts of the body through the agency of the nadis. The brain lies
asleep, but the mind knows no peace. In Yoga, the mind is supposed to have three parts-
Conscious, subconscious and unconscious. We make use of only a little energy
generated by them. The major part of the energy of the mind remains unused. It is
only the practitioners of Yoga that can benefit from the unlimited potentiality of the
mind. It is so subtle in nature that it is impossible to measure its length and breadth.
It is made up of extremely subtle waves or threads. In moments of anger it assumes
the form of formidable hatred. IN hours of greed it is saturated with passion and
attachment. The mind can observe anything not visible to the naked eye. Mind is also the
creator of the dream world.
Mind also gives rise to different feelings-sharpness valour, peace,
deceptiveness etc. It has the capacity to swallow any form or shape, no matter
howsoever big or small it may be. Mind is the only substance that haunters round the

interior and the exterior of the body. Desire, thought and action are three corollaries
of the Mind. In its very nature it is liable to change any time and every time. In dream
it creates its own world, in sushapti (deep sleep) it ceases to exist.

Dazzled by the fascination of the materialistic life the modern man is busy only in the
discovery of the external objects of the world. But has perhaps no time or curiosity to
understand the structure of his own body. Is it not an irony of ironies that we are
completely ignorant of the structure of the body through the medium of which one
carries out all the activities of life, understands all things of life and carries on the
various researches. It is, therefore, necessary to know about its important organs. A
general knowledge of these organs will prove very useful for the practice of Yoga.
There are three parts of the body :
(1) The Physical Body
(2) The Astral Body
(3) The Causal Body
Discussion of the Astral and the Causal bodies will be found in the chapter on
“Pranayam”. Here we shall try to describe the structure of the Physical Body for
the benefit of the common man who should be familiar with the general
knowledge of the main organs of the human body.


Cells are those small units of the living organism that form the fundamental
basis in the making of the humans and other beings. They are not visible to the
naked eye, therefore, can be observed only by the microscope. In spite of being
different from one another they possess certain similarities, One will be surprised to
know that their number has been estimated to be 6000 billion. Cells perform different
functions. For example, tissue cells expand and contract. They are also present
under the layers of the skin. The brain cells are helpful in the thinking process. Eye
cells transmit rays to the brain. The beatings of the heart lead to the expansion of
the heart through the process of breathing. It is all the work of the cells. Not only this
they also provide energy in the blinking of the eyes, raising of the hands and such
other movements of the body organs. How many cells are built in a minute and
destroyed in the functioning of the body is difficult to speculate? In itself, it is altogether a
different world. In spite of their huge number, they work in complete union with one-
Functions: Primarily, the cells perform some important functions. Their main
function is to provide the raw material, convert it into the natural product and then
to work on the unused portion. The mainstream of life is so inextricably connected
with them that life continuous so long as the dead cells are replaced by the new


Different kinds of cells :

  1. Mitochondrion
  2. Ribosome
  3. Nucleus
  4. Vacuole
  5. Cytoplasm


A group of Cells is known as tissue which only performs one type of specific


When tissues perform collectively different functions of some particular part of
the body, which can be identified from other parts by its shape and qualities, that
particular part is called an organ, e.g. brain, liver, stomach etc.

Understanding a SYSTEM

When a group of many organs work together for a particular kind of function, it
is known as a System. There are nine such systems in our body.
As a result of the different Yoga practices, there is a lesser possibility of the
destruction of elimination of cells and a greater possibility of their formation. This is a
very important secret of the maintenance of one’s health and prolongation of youthful
The main systems to understand are

  • Nervous System
  • Glandular System
  • Digestive System
  • Excretion System
  • Respiratory System
  • Circular System

What is the Importance of Yoga?

When we get something, we enjoy it, we are lured by it and get enthused by its possession. But what one should realize is: how far is it wise to desire a thing which is temporary in nature, with which we have to part one day or the other and which is bound to cut the very roots of our life. The question, therefore, arises: what should man aspire to in his life? The answer lies in Yoga. Yoga alone has the potential to give what we expect of life.
Let me be happy. Let my family, neighbors, and community be happy, let my province, country, and the entire world be happy. Yoga alone will help us in taking such a vow and affect the implementation. Yoga alone can show us the path of peace and happiness. It alone helps us in developing our personality and also a sound and disciplined life. Details