The visual system, the sensibility of real

Synchronization cycle

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who are we, where are we from, where are we going. We are sentient beings who create every moment of our life from the past to a future that only exists in our imagination. To bring your imagination to life, the fewer intermediaries there are, the less possibility there is to go wrong. We can create a world of Peace, following the laws of Nature, dictated by our Humanity.

To learn to dominate nature, learns already to obey it.
« The name of the Rose »
by Jean-Jacques ANNAUD

The visual system, the importance of integration for a fresh start, and of covering as many directions as possible to increase the sharpness and accuracy of physical reality:

Multi-directional to capture everything

The light passes through the refractive media (cornea, aqueous humor, lens and vitreous body) of the eye to reach the nerve retina.

  • Sclera: Outer fibrous tunica of the eye bulb;
  • Cornea: Transparent part of the outer tunica: very sensitive to pain;
  • Choroid: Middle vascular tunic of the eyeball;
  • Ciliary body: Anterior vascular and muscular extension of the choroid;
  • Ciliary process: Radiant pigmented folds of the ciliary body: secreting the aqueous humor that occupies the anterior and posterior chambers;
  • Iris: Contractile diaphragm with a central opening (the pupil);
  • Lens: Transparent lens held in capsule form by consular fibers;
  • Retina: Photoreceptor tunica at the origin of the optic nerve (optic retina);
  • Macula (yellow spot): Retinal area of ​​maximum visual acuity;
  • Optic disc: The non-receptive area through which the axons of the optic nerve (Cranial Nerve II) leave the retina towards the brain.

A refractive medium changes the direction of the light rays, which means that the light will flood the bulb of the eye, and thus, the nerve retina will be fully illuminated.

From infinity small to infinity large

The ciliary body has smooth muscle organized in a circular fashion like a sphincter.

  • When this muscle is relaxed, traction is exerted on a set of zonular fibers attached to the elastic lens, which is then stretched and flattened, allowing objects to be seen at a distance far from the eyes;
  • When the gaze is focused on a nearby object, the ciliary muscle like a sphincter contracts, and approaches the lens, causing relaxation of the zonular fibers and allowing the faces of the lens to bulge for accommodation;
  • This accommodation reflex is controlled by the parasympathetic fibers of the oculomotor nerve (Cranial Nerve III).

The iris also has smooth muscle fibers.

  • The contraction of the circular pupillary sphincter muscle, under the control of the parasympathetic fibers of the NC III, leads to a reduction in the diameter of the pupil,
  • While fibers of the pupillary dilator muscle under sympathetic control increase the diameter of the pupil.

The part of the retina directly opposite the focal point of the lens at the posterior pole of the eyeball is specialized.

  • There is an area called the macula (yellow spot) with a small central pit called fovea centralis.
  • In the fovea, the retina is thinned and contains only cones and ganglion cells and is the region of greatest visual acuity.
  • The macula contains a lot of cones and a few rods, apart from the macula rods dominate.
  • Each human retina has about 7 million cones and about 120 million rods.

The bulb of the eye is attached to the orbital cavity by six extra-ocular muscles that move it, and it is cushioned by the fat that envelops the posterior two-thirds of the globe.

The need for the limits

The retina is a thin tunica that forms an expansion of the brain.

Most of the axons of its ganglion cells travel back through the optic nerve (NC II) and the central nervous system (CNS) to their synaptic region in the lateral geniculate body of the thalamus.

For this, the light must pass through the entire thickness of the retinal tunic:

  • To finally meet the photoreceptor cells located on the pigment epithelium;
  • Photoreceptors (rods and cones) synapse with bipolar cells,
  • The bipolar cells then establish a synapse with the ganglion cells,
  • while horizontal and amacrine cells make interconnections.
  • The cones are specialized in bright light vision (daytime),
  • The rods in twilight vision (night).

The pigment epithelium absorbs light, so only light rays that have passed through the eye bulb directly or by refraction will be transformed into nerve signals by the nerve retina, and sent to the brain.

The pigment epithelium also participates in immune modulation;

Let’s use the observation of feedback to readjust our actions:

If we considered Humanity as a human body,
where each of Us lives his own life;

If we considered Humanity as a human body,
where each of Us lives his own life;

Humanize the World,
we will free ourselves from our fears,
misery, violence, injustices, wars,
like the visual system let us observe the Earth in detail as a whole.


Bibliographic References:
– The information on the visual system is taken from the book « The Netter’s Anatomy Coloring Book », John T. HANSE, Elsevier Masson SAS, 2017 (the french version),
– The pictures are taken from the book « Atlas of Human Anatomy », Seventh edition, Franck H. NETTER, Elsevier Masson SAS, eBook.

The inner ear, the transfert of vibrations

Exchanges cycle

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Perhaps we must accept that the division, the war, the violence, the diseases, benefit some who will do nothing to change that. Not everyone wishes, consciously or unconsciously, to live in Peace on Earth. But they are not “Life”. Life is Life. We are Humanity. We carry out at the individual level through our daily acts, at the citizen level with petitions, associations, fraternal actions. We can achieve it on a global scale with movements of movements, for Peace, for Justice, for the Joy of Living, for Freedom: a Movement of Movement For.

Man is born barbarous.
He is ransomed from the condition of Beasts, only by being cultivated.
 » The courtiers manual oracle – To cultivate and embellish »
by Baltasar Garcián, 1601-1658

The inner ear, the movement of a fixed point that becomes mobile and changes the encoding of data to make systems that everything separate:

The wave that propagates

Waves of sound arrive in the outer ear and cause vibrations in the tympanic membrane.

  • These vibrations in turn generate the movements of the ossicles responsible for the vibrations of the stapes in the vestibular window (oval),
  • leading to mobilize in waves the liquid (perilymph) located in the vestibular ramp and the tympanic ramp of the cochlea,
  • which eventually causes the tiny hair cells of the organ of Corti to tilt and depolarize.
  • Action potentials ensue in the afferent axons of the spiral ganglion cells, which are then transported centrally to the cochlear nucleus of the elongated cord.

From this nucleus, information is transferred to overlying centers in the brain and ends in the auditory cortex of the temporal lobe.

Complementarity at the service of action

While half of the nerve fiber contingent in the vestibulo-cochlear nerve (Cranial Nerve VIII) carries auditory information, the other half carries sensory information in maintaining a specialized sense of balance.

Receivers intended for balance are specific in two functional aspects:

  • Static: a special receptor called an acoustic macule resides in each utricle or saccule and helps analyze head position, linear accelerations, as well as gravity and low frequency vibrations (saccule only);
  • Dynamic: special receptors called the ampullary crest sit in the bulb of each semicircular canal (anterior bulb, lateral bulb, posterior bulb) and are affected by the angular (rotational) movements of the head

Vertigo is a sensation of spinning motion with loss of balance (dizziness).

It can occur by excessive stimulation of the vestibular system as in seasickness, motion sickness (car), carousel rides.

Viral infections, certain medications, and tumors can cause dizziness.

From oscillations to nerve impulses

The important step in the auditory transduction pathway is the transformation of mechanical vibrations leading to neural action potentials which are then transported to the brain.

This step occurs in the organ of Corti in the cochlea:

  • Cochlear hair cells (internal or external) sit on a basilar membrane and are functionally organized.
  • Pressure waves in the vestibular ramp are transmitted to the endolymph that occupies the cochlear duct through the vestibular membrane.
  • These pressure waves mobilize the basilar membrane (the loudest sounds induce more movements) but also the tectorial membrane.
  • Hair cells resting on the basilar membrane have the end of their cilia attached to the tectorial membrane and the divergent movements of these two membranes result in a shearing motion.
  • This effect leads to tilting of the cilia, depolarization of hair cells, release of neurotransmitters and initiates the action potential in the afferent axons of spiral ganglion cells.

The acoustic macule (of the vestibular apparatus of equilibrium) also carries hair cells (like the organ of Corti above) and a simple kinocilium (the longest eyelash) is present and covers the end of each bundle of stereocilia (very long microvilli).

  • During linear acceleration, the cilia move and this movement results in an increased release of neurotransmitters to the sensory axons of the cells of the vestibular ganglion.
  • This occurs when the cilia move to and from the kinocilium, causing depolarization of the hair cells.
  • The movements of the cilia away from the kinocilium causing hyperpolarization of hair cells, reducing the release of neurotransmitters.
  • Finally, the macules of the utricle feel the accelerations in a horizontal plane,
  • while the macules of the saccule perceive vertical accelerations, the sensation perceived when taking the elevator.

The ampulla crest of semicircular canals also possess hair cells and a kinocilium like a macule.

Let’s use our body’s feeling and its ability to transform it into analyzable data to amplify our sensitivity to Living:

If we consider any movement (of people, animals, nature)
as a displacement of space generating a vibration,
and our skin as a vibratory sensor;

Developing our senses can give us the opportunity to know the world;

Let’s decide to tame our feelings,
we will find how to live together.


Bibliographic references:
– The information on the auditory and vestibular system and the picture of hair cells, are taken from the book « The Netter’s Anatomy Coloring Book », John T. HANSE, Elsevier Masson SAS, 2017 (the french version),
– The other three pictures are taken from the book « Atlas of Human Anatomy », Seventh edition, Franck H. NETTER, Elsevier Masson SAS, eBook.

The nervous system, the intricate paths

Delimitation cycle

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When he gave his « I have a dream » speech in 1963, Martin Luther King was not to imagine that 45 years later, a black man would be President of the United States. This has not, however, changed the discrimination that some people have towards people who are different from themselves. Yet the strength of humanity is in the diversity of human beings that compose it.

Life will never be anything other than what we do with our lives.
« Oh my God! » by Tanya Wexler

The nervous system compiles information of a different nature in order to generate the best action that will maintain the integrity of the human body:

Always in threes, information travels

The structure of neurons -nerve cells- reflects its functional characteristics.

The neuron carries efferent information through an action potential:

  • Dendrites capture information from the external environment and propagate it to the cell body;
  • The cell body or pericaryon, soma, contains the nucleus, a single axon leaves it;
  • The axon carries information to target cells or another neuron, where it will pass it through specialized junctions called synapses.

Although the human nervous system has over 10 billion neurons (a more than rough estimate), they can nevertheless be classified into one of three functional types:

  • Motor neurons: carry efferent impulse from the central nervous system (CNS) or ganglia (a group of cell bodies of neurons outside of the CNS) to target cells (effectors).
    – Somatic efferent axons target skeletal muscle,
    – Vegetative efferent axons (visceral) target smooth muscle, heart muscle and glands.
  • Sensory neurons: carry related information from receptors to the CNS.
    – Afferent somatic axons carry pain, temperature, tactile sensations, pressure and proprioception (unconscious),
    – Vegetative (visceral) axons carry pain and other sensitivities (such as nausea) from the viscera, glands and smooth muscle to the CNS.
  • Interneurons: transmit information between sensory and motor neurons, thus forming an integrated network between cells. They probably make up over 99% of all neurons in the body.

In the CNS, axons are myelinated by an oligodendrocyte (a glial cell or neuroglia) while axons in the peripheral nervous system (PNS) are surrounded by a Schwann cell (a glial cell), without all being myelinated, but when they are, it is the Schwann cell that myelinates them.

Two signals for orientation

The nervous system is made up of two anatomical parts with specific roles:

  • The central nervous system (CNS): the brain and the spinal cord, it is the center of regulation and integration;
  • The Peripheral Nervous System (PNS): Cranial nerves, spinal nerves, and ganglia, these are the lines of communication between the CNS and the body. It splits into two ways:
    – The sensitive pathway (afferent) which contains somatic and vegetative neurofibers (axons and dendrites) and propagates nerve impulses from receptors to the CNS,
    – The motor pathway (efferent) which contains somatic and vegetative neurofibers and propagates nerve impulses from the CNS to the effectors (muscles and glands).
    The motor pathway will then divide into two with the somatic nervous system and the autonomic nervous system
    which in turn will split into two with the sympathetic nervous system and the parasympathetic nervous system.

Within the CNS, there is a fundamental binary distinction, concerning the distribution of synapses.

The gray matter:

  • It is a region where synapses (interneuronal connections) are established;
  • It contains all cell bodies, all CNS synapses, and capillaries;
  • The cells of the neuroglia (the supporting and protective cells of neurons) are: astrocytes, oligodendrocytes, microglia.

The white matter:

  • It is a region devoid of synapses;
  • It consists mainly of bundles of myelinated axons (grouping of bundles),
  • The cells of the neuroglia are the oligodendrocytes for the CNS; and Schwann cells for SNP.

The distribution of gray matter and white matter differs between the brain and the spinal cord:

  • In the brain, the gray matter is peripheral, it defines a cortex around the central white matter.
  • In the spinal cord, the gray matter and the cell bodies of the neurons that correspond to it are located in the central part of the spinal cord, where they describe a butterfly or H-shape that can be distinguished from the white matter around.

The SNP is made up of 31 spinal nerves that emerge from the spinal cord at the level of the vertebrae.

There are 8 cervical pairs, 12 thoracic pairs, 5 lumbar pairs and a coccygeal pair.

Each spinal nerve is formed:

  • From a ventral root: for the motor skills of the limbs,
  • From a dorsal root: for the sensitivity of the limbs.

The ventral branches converge to form plexuses.

Crosses to balance

A plexus is not much different from a large network of different rail tracks that connect into a main track such as a rail yard.

The nerve plexus is a mixture of nerve fibers originating from spinal nerves of adjacent levels, which ultimately distributes itself into several « terminal » nerve branches, which reach the peripheral regions and innervate its skeletal muscles, joints, and skin.

Nerve fibers are of three types:

  • Somatic motor nerve fibers to innervate skeletal muscles;
  • Sympathetic postganglionic nerve fibers intended to innervate the smooth muscle of hair follicles, vessels and sweat glands;
  • Sensitive nerve fibers to give the central nervous system information from the outside world, captured at the level of the skin.

Here is an example of the description of the brachial plexus formed by the ventral branches of the C5-T1 spinal nerves:

  • The roots: The five ventral branches of C5-T1 constitute the “roots” of the plexus;
  • The trunks: The five roots reorganize into three upper, middle and lower trunks which engage under the collarbone in front of the first rib;
  • The divisions: Each trunk gives two divisions: an anterior division and a posterior division, and therefore six divisions in total;
  • The cords: the three posterior divisions combine to form the posterior cord, the medial and lateral cord are made up of the combinations of the anterior divisions;
  • Terminal branches: The plexus gives rise to five large branches that innervate the shoulder, arm, forearm and hand.

A number of small nerves arise from this organization (5-3-2-3-5) to innervate some muscles of the back, and of the anterior and lateral region of the rib cage.

Let’s use the foundation offered by a triangular base and the amplitude of binary complementarity in order to experience common happiness:

If the human body is able to coordinate all the information
that these sensors send him to take actions, without losing his balance,
by alternating a base containing 3 types of data and binary limits;

We can define scales at three levels for observing the world
{Global – National – Individual} {Private – Professional – Citizen};
and define binary signals to guide our common choices
{war – peace} {freedom – comfort};

Let’s try to keep the world in balance,
let’s decide together the vital signals to live in harmony.


Bibliographic references:
The information on the nervous system ies taken from:
– the book « The Netter’s Anatomy Coloring Book », John T. HANSE, Elsevier Masson SAS, 2017 (the french version),
– the first year medical course.
The picture of the neuron is taken from the book « The Netter’s Anatomy Coloring Book », John T. HANSE, Independently published, 2019 (the french version).
The picture of the brachial plexus is taken from the book « Atlas of Human Anatomy », Seventh edition, Franck H. NETTER, Elsevier Masson SAS, eBook.

The endocrine system, listen to act

Synchronization cycle

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Democracy is the power of the people, by the people, for the people. It is a political system, which starts from the needs of the people and arrives at the establishment of a way of life, to live together so that everyone can find their way there. No country is democratic taking this definition into account, the current political systems lead to violence, misery, injustices. We can free ourselves from fear, by freeing ourselves from duality.

THE artist is the creator of beautiful things.
To reveal art and conceal the artist is art’s aim.
« The picture of Dorian Gray »
by Oscar WILDE

The endocrine system, the targeted and coordinated multiplicity to balance the functioning of the body:

The number to act in depth

The endocrine system is dispersed and critical for regulating the major functions of the body.

There are many hormones that interact at target sites (cells and tissues) even from a long distance, releasing hormones into the circulating blood flow.

Here are the tissues and organs involved in the endocrine system with their distribution in the body:

  • In the brain: the hypothalamus, the pineal gland, the pituitary gland;
  • In the neck: the thyroid gland, the para-thyroid glands, the thymic gland;
  • In the thorax: the heart;
  • In the abdomen: the digestive tract, the adrenals, the pancreatic islets, the kidneys;
  • In the pelvis: the ovaries, the testicles;
  • At the tissue level: adipose tissue, some connective tissue cells, white blood cells.

Hormones can act on a wide variety of cellular interactions involving communication:

  • Autocrine: on a cell of the same type or on the cell having, itself produces the signal ;
  • Paracrine: on a cell in the nearby of the emitting cell;
  • Endocrine: at a great distance through the blood flow;
  • Neurocrine: like a neurotransmitter but released into the circulating blood flow.

The endocrine system, along with the nervous system and the immune system, facilitates communication, integration and regulation of many body functions.

Unique configurations to punctuate life

Puberty only occurs once in life, between 10 and 14 years, for the functional maturity of the reproductive organs in both sexes, and the appearance of secondary sexual characteristics.

The following events occur:

  • The hypothalamus increases its level of gonadoliberin (GnRH) release;
  • GnRH stimulates the production of luteinizing hormone (LH) and follicle stimulating hormone (FSH) by the anterior pituitary gland;
  • In the female sex: LH targets the ovaries stimulating the production of androgens transformed into estrogen, LH also stimulates the production of progesterone, and FSH stimulates the production of estrogen from androgens;
  • Estrogens are responsible for modifications of the accessory sexual organs and secondary sexual characteristics recognizable at puberty;
  • In the male sex: LH acts on the testes to stimulate the production of testosterone, testosterone and FSH act together on the testicle to promote the development of the spermatozoa;
  • Testosterone is responsible for the modifications of the accessory sexual organs and the secondary sexual characteristics recognizable at puberty.

Pregnancy is also a unique, non-cyclical event, which induces a particular set of hormones, but unlike puberty, it can occur several times in life or never.

Cycles to accord the present

During the day, depending on our activity, the fact that we eat, that we sleep …, the energy needs of the body can be reversed.

The main fuels in the body are glucose, fatty acids and ketones (derivatives of fatty acid metabolism).

The pancreas secretes, among other things, two hormones with opposite hormonal functions.

Glucagon, the hormone for energy mobilization:

  • Glucacon acts on the liver to degrade glycogen and stimulate hepatic neoglucogenesis from amino acids;
  • There is an increase in the concentration of glucose in the blood;
  • It also acts on adipose tissue to stimulate lipolysis and the release of fatty acids.
  • The overall effect of glucagon is to increase blood levels of glucose, fatty acids and ketones.

Insulin, the energy storage hormone:

  • Insulin secretion rises with increasing plasma glucose level, especially after meals;
  • It stimulates the cellular penetration of glucose, where it is stored in the form of glycogen (particularly in the liver and muscles);
  • It also stimulates the formation of fats and inhibits lipolysis;
  • It stimulates the cellular entry of amino acids and their storage in the form of proteins.
  • The overall effect of insulin is to lower blood glucose and ketone levels.

There are many other hormones that interact at different levels and locations in the human body to regulate and coordinate the body.

Let’s use the feedback from hierarchical exchanges to harmonize our relationships:

If we consider Humanity as a human body,
where each of Us communicates with our environment;

We will be able to know what is happening at every point of the globe
and adjust when necessary, our way of life;

Humanize the World,
we will balance together
climate change, the spread of the coronavirus,
as the endocrine system unites for the well-being of the organism as a whole.


Bibliographic reference:
– The information on the endocrine system is taken from the book « The Netter’s Anatomy Coloring Book », John T. HANSE, Elsevier Masson SAS, 2017 (the french version).

The reproductive system, the involuntary will

Exchanges cycle

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On paper, with words, in his head, it is possible to realize his most wonderful dreams. But when we move on to realization, we always come up against unforeseen obstacles, which sometimes ruin our momentum. Duality is the natural state of the evolution of life, its extremities can be used as the limits to have in mind, to progress between the two in balance.

It is not power that corrupts but fear.
Fear of losing power corrupts those who wield it and
Fear of the scourge of power corrupts those who are subject to it.
« Freedom from fear »
by Aung San Suu Kyi

The reproductive system, automatic processes sprinkled with wishes to evolve in complete freedom:

Physical difference and identical function

In the human body, the reproductive system has the most differences between women and men, while having the same functionality.

Female organMale organFonctionality
OvariesTestesGerm cell production and hormone secretion.
Uterine tubesDuctus deferensTransport of germ cells.
Paraurethral glands, Skene’s glandsSeminal vesiculesSeminal fluid production.
Greater vestibular glandsBulbourethral Glands,
Cowper’s glands
Production of a clear, viscous, lubricating liquid.

The feminine and masculine germ cells do not have the same characteristics of life and diffusion, they require a different structural organization, while respecting identical needs.

Automatic actions

There are events in the reproductive system that we cannot guess.

Today we know that hormones play a big role in orchestrating the reproductive system. They are known, the interactions between each can be modeled and used for medical purposes.

Here are some steps that seem escape to a voluntary control:

  • In women, at each ovulation cycle, about 10 to 20 prenatal follicles begin to mature to give an ovum, but only one becomes dominant and the others degenerate;
  • In men, an erection results from parasympathetic stimulation, which causes relaxation of the smooth muscles of the wall of the arteries vascularizing the erectile bodies and allowing the blood to engorge the vascular sinuses of erectile tissues;
    The parasympathetic system controls the involuntary activities of organs, glands, blood vessels.
  • In men, when the urethra detaches from the bladder, it is surrounded by a smooth muscle sphincter, the internal urethral sphincter. This sphincter is under sympathetic control and closes the urethra during ejaculation so that the semen cannot retrograde reach the bladder.
    The sympathetic system controls of a large number of automatic body activities, such as heart rate or contraction of smooth muscles.

When we acquire knowledge, it would be good to distinguish what is related to human biology and can be used for therapeutic purposes, from what is related to free will and must remain the experience of life.

Plan everything for creation

The menstrual cycle prepares the uterus to receive the fertilized egg and to participate in its embryonic development.

Every month, from puberty to menopause, the woman undergoes the monthly cycle that will allow her to carry life.

For this, the monthly cycle is accompanied by the following changes in the endometrium of the uterus:

  • The monthly phase: it lasts 3 to 5 days and marks the beginning of the cycle when the endometrium degenerates because no implantation has taken place, and undergoes elimination with the monthly flow.
  • The proliferative phase: from the 4th to the 14th day approximately, when the endometrium thickens considerably; this growth is stimulated by estrogen;
    It coincides with the follicular phase of the ovarian cycle, which sees the proliferation of granulosa cells in a selected follicle.
  • The secretory phase: after ovulation, which is the 14th day of the ovarian cycle, the endometrium increases its secretory activity (nutrient-rich mucus) under the influence of progesterone (hormone that promotes gestation). It becomes thick and edematous in order to anticipate possible implantation;
    At this time, the ovarian cycle is in its luteal phase during which the follicular cells transform into a corpus luteum and produce significant quantities of progesterone, but also of estrogen and inhibin.
  • In the absence of fertilization, degeneration of the corpus luteum, and so decrease of the plasma levels of oestrogen and progesterone, begins around the 25th day of the cycle and menstruation appears around the 28th day, defining the start of a new menstrual cycle.
  • If fertilization and implantation occur, then the plasma levels of estrogen and progesterone continue to rise, with stimulation of endometrial growth by estrogen and inhibition of uterine contractibility by progesterone, so that the fetus can reach its term (9 months) before birth.

At each ovulation, one of two actions: fertilization takes place or fertilization does not take place, occurs, regardless of the attention we pay to it.

Let’s use the « will / involuntary » duality contained in creative exchanges to raise our consciousness:

If we consider that our dreams are the involuntary part of creativity,
and society the place of expression of our will to give them life;

Developing conscious societies can offer the freedom to realize them;

Let’s decide to exchange our thoughts, we will create an awakened world.


Bibliographic reference:
– The information on the reproductive system is taken from the book « The Netter’s Anatomy Coloring Book », John T. HANSE, Elsevier Masson SAS, 2017 (the french version).

The gastrointestinal system, mobile at the same time

Synchronization cycle

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to live in a spirit of fraternity is to freely express one’s personality, without imposing one’s opinions and beliefs on others. It is giving value to Life. Fraternal gestures are spontaneous and not calculated, coming from the heart they bring well-being to the one who gives them and the one who receives them.

Darkness cannot drive out darkness; only light can do that.
Hate cannot drive out hate; only love can do that.
Martin Luther King

The peculiarity of the gastrointestinal system is to be able, to digest, to absorb, to regulate unknown foods, in a short period of time and to provide energy to the body:

The delimitation to fulfill functions

The gastrointestinal system consists of a conduit -the digestive tract of about 10 meters starting from the oral cavity and extending to the anal canal, and associated glands.

The digestive tract includes:

  • The oral cavity: the tongue, teeth and salivary glands;
  • The pharynx: the throat subdivided into naso-pharynx, oropharynx and laryngo-pharynx;
  • The esophagus;
  • The stomach ;
  • The small intestine: the duodenum, jejunum and ileum;
  • The large intestine: the cecum, the ascending colon, the transverse colon, the descending colon, the sigmoid colon, the rectum and the anal canal.

The associated glands are:

  • The salivary glands: three major glands and thousands of tiny and microscopic minor salivary glands dispersed in the oral mucosa;
  • The liver: the largest gland in the body;
  • The gallbladder: stores and concentrates the bile necessary for the digestion of fats;
  • The pancreas: an exocrine gland (producer of digestive enzymes) and endocrine.

The digestive tract imposes the direction, order and speed of digestion of nutrients from the mouth to the anal canal, the glands intervene independently of the food bowl.

Active / passive duality

Certain stages of the digestion process involve an action on our part and are under the control of the central nervous system (CNS), while others are under the control of the autonomic nervous system (ANS) and we will be passive in carrying them out.

  • Brushing teeth eliminates food flows to prevent cavities. When the lower esophageal sphincter -a smooth muscle controlled by the ANS- loses its tone, it lets stomach acid go up, which can damage the health of the teeth.
  • We can decide not to swallow the food we have in our mouths. As soon as swallowing begins, the smooth muscles of the esophagus -under control of the ANS- will contract automatically to bring the food bowl down to the stomach. The stomach -itself made up of smooth muscles- will contract and the digested food will reach the duodenum, and continue on its way to be absorbed.
  • The bile, necessary for the digestion of fats, is produced by the hepatocyte cells of the liver. It is discharged into the bile duct, either it directly reaches the duodenum, or it goes into the gallbladder where it will be stored and concentrated. The liver produces about 900 ml of bile and the gallbladder has a storage capacity of 30 to 50 ml. The bile will leave the gallbladder under a stimulating effect resulting from the ANS and the hormonal system.
  • The anal canal is closed thanks to the tonic contraction of the internal anal sphincter -a smooth muscle under the control of the ANS, and the external anal sphincter -a skeletal muscle under the control of the CNS. When the rectum is distended by the feces, the internal sphincter relaxes, but defecation can only occur with voluntary relaxation of the external sphincter and contraction of the smooth muscles of the distal colon and rectum.

Even if the course of the digestive tract and the digestive functions are the same for everyone, the passive intervention of the autonomic and hormonal nervous systems means that the absorption resulting from the ingestion of the same food by two people, will not be not necessarily identical in the two organisms.

Mobility develops interactions

When the digestive tract of the embryo, suspended by the mesentery, begins to grow in length and in width, it undergoes a rotation on itself so that the intestinal length necessary for a complete digestion can be positioned in the constrained space of the abdomen.

As intestinal rotation and growth takes place, part of the intestine and associated digestive glands is pushed back to the posterior abdominal wall, adjoins it and merges with the posterior peritoneum, losing its meso and thus becoming retroperitoneal.

Other parts of the intestine keep their mesentery and thus continue to be intraperitoneal.

Here are the different parts of the gastrointestinal tract, in the order of intervention in the digestive system, and their relationship to the peritoneum:

Parts
of the gastrointestinal tract
Relation avec le péritoine
StomachIntraperitoneal
DuodenumRetroperitoneal
Jejunum and ileumIntraperitoneal
Ascending colonRetroperitoneal
Transverse colonIntraperitoneal
Descending colonRetroperitoneal
Sigmoid colonIntraperitoneal
RectumRetroperitoneal

All parts of the digestive system come from the embryonic digestive tract. Its transformation during embryogenesis – by rotations, plicatures, delimitations – means that one in two parts has retained its mesentery, or on the contrary has lost it.

Let’s use the inter-dependence of synchronized delimitation to live in the present moment:

If we consider Humanity as a human body,
where each of Us sets life in motion;

We can work together for common happiness;

Humanize the World,
we will get peace on Earth, like the harmony of a body.


Bibliographic reference:
– The information on the gastrointestinal is taken from the book « The Netter’s Anatomy Coloring Book », John T. HANSE, Elsevier Masson SAS, 2017 (the french version).

The respiratory system, support comes from within

Exchanges cycle

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Humanity, on the scale of life, it is a one year child on the scale of human life. We know that he will run, eat alone, write, work … but currently, he is dependent on his family environment, himself dependent on what society propose him. To create a fraternal world, we must participate individually in collective orientations, and collective organizations must pay attention to individuals.

The only way to accomplish the impossible is to believe it is possible.
« Alice in the Wonderland »
by Tim BURTON

The respiratory system, a path traveled by the elements exchanged to create actions:

To respond to needs

The respiratory system supplies the body with the oxygen it needs for its metabolic needs, and removes carbon dioxide.

To study the biological function linked to the respiratory system, it is not enough to study the part which deals with the exchanges between oxygen and carbon dioxide, but the whole path of oxygen and carbon dioxide.

This means that, structurally, the respiratory system has:

  • The nose and paranasal sinuses;
  • The pharynx and its different parts: the nasopharynx, the oropharynx, and the laryngo-pharynx;
  • The larynx;
  • The trachea;
  • The bronchi, bronchioles, alveolar ducts and bags, and the alveoli;
  • Lungs.

An external element entering the human body follows a defined path.

A defined path to carry out actions

The organs involved in the respiratory system are mainly covered with ciliated respiratory epithelium. Certain parts are innervated and vascularized.

This allows the respiratory system to perform five functions.

  • Filter, humidify the air and mobilize air to and from the lungs;
  • Present a large gas exchange surface with blood;
  • Help regulate the pH of body fluids;
  • Contribute to phonation;
  • Participate in the olfactory system with odor detection.

It is the fact that oxygen travels through different parts of the body that allows it to perform specific actions.

The exchange is spontaneous

The lungs, the only place for gas exchange, supply the blood with oxygen and take up carbon dioxide.

If oxygen, during its path, between the oral cavity and the lungs, can cause different actions of the body, depending on the presence of dust, cold air … and this during a certain time.

The gas exchange between blood and air will always be identical and almost instantaneous:

  • When blood travels through the alveolar capillaries, oxygen diffuses to the red blood cells, where it is linked to hemoglobin;
  • At the same time, the CO2 detaches from the red cells and diffuses towards the alveoli;
  • Normally, the blood crosses the entire length of the alveolar capillaries in 0.75 seconds, see more quickly if the heart rate is high.
  • The interalveolar septum (separating the alveolar air space from the capillary lumen) is a very thin air-blood barrier. It promotes the rapid diffusion of gases.

Gas exchanges are so efficient that they only take 0.5 seconds.

Let’s use the creative functions of exchange to develop Common Happiness:

If we consider our dreams to be oxygen,
and dialogue is the path that gives them life;

Sharing our dreams can offer the possibility of realizing them;

Let’s decide to create exchange structures,
we will live our waking dreams.


Bibliographic reference:
– The information on the respiratory system is taken from the book « The Netter’s Anatomy Coloring Book », John T. HANSE, Elsevier Masson SAS, 2017 (the french version).

The immune response, self-awareness

Delimitation cycle

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everything is possible when we are children, since everything is new, discovery, magic. We fully live the present moment, without seeking to achieve a particular goal, under the caring eye of the parents. As adults, we have learned that each act has consequences, with advantages and disadvantages, and out of fear, we often limit our choices. If to live humanely, it was the attention paid to his adult choices, with the aim of living fully the present moment as a child.

Live simply
so that others may simply live.
Mahatma GANDHI

The immune response combines three characteristics to react to the outside world:

Protect yourself from visible physical obstacles

The body’s first line of defense is made up of non-specific barriers.

  • The skin and mucous membranes that cover the outside of the body, or the respiratory, gastrointestinal, urinary and reproductive systems, which produce additional barriers: mucous secretions, enzymes and their acidity;
  • Hunting mechanisms such as tears and urination;
  • Thick, sticky mucus to sequester pathogens;
  • Strong cough or sneezes.

These elements are intended to preserve the interior of the healthy body.

Symptoms to show the invisible

The second line of defense is innate.

It intervenes if the non-specific barriers are exceeded.

It involves:

  • Many cells;
  • Antimicrobial products;
  • Mechanisms of inflammation.

It shows symptoms:

  • Redness;
  • Fever;
  • Sweats;
  • Pain.

These elements call for the person to rest, or protect the injured part of his body, to give the body time to regenerate, thanks to the innate immune response.

A specific, systemic, memory response

The third line of defense is characterized by the specific recognition of a specific pathogen, and a rapid response against iterative invasion of the pathogen.

Take the example of B cell activation:

  • The B lymphocyte recognizes the pathogen by an antibody attached to its surface. This antibody is specific for the antigen and the B lymphocyte becomes sensitized;
  • The B lymphocyte is then activated when an inactive T helper lymphocyte recognizes the same antigen. linked to the B lymphocyte, and secretes lymphokines which lead to the division of the sensitized B lymphocyte;
  • The division of this B lymphocyte generates millions of B cells, which transform into plasma cells which then secrete antibodies specific for the antigen, in the blood and the lymph;
  • These circulating antibodies bind to this specific antigen of the pathogen and make it accessible to its destruction by phagocytes. Antibodies can also bind directly to bacterial toxins or to receptors used by bacteria and viruses so as to neutralize the invader;
  • The division of B cells also leads to the memorization of aggression and of the response in the event of re-exposure of the organism to the same foreign antigen, thanks to memory T lymphocytes.

It is thanks to a structured coordination of B, T lymphocytes and the intervention of other different elements such as macrophages, that the body can neutralize pathogens and regain its health.

Let’s use protection, attention, dialogue, to learn to gain self-confidence for your choices:

If the human body is able to distinguish a pathogen
from a normal body cell,
thanks to the molecules present on their surface;

We can learn to dialogue with our body, and know
when it is in good health,
when it is in the presence of danger,
when it needs nurse oneself;

Let’s try to get to know each other,
in order to recognize ourselves among others,
we discovered the freedom to live together.


Bibliographic reference:
– The information on the immune response is taken from the book « The Netter’s Anatomy Coloring Book », John T. HANSE, Elsevier Masson SAS, 2017 (the french version).

Molecular signaling, the might of the cohesion

Synchronization cycle

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Life is Magic, it does not judge, it is Just. If we are wrong, she lets us do it, she accepts our choices. She just sends us messages in response to her choices -illnesses, disasters,… a friend, a job,… a cloud that comes to life, a break through the clouds,… Choosing a harmonious source of aspiration, brings the health, the joy, the prosperity.

You know the theory of rational choice Dom.
There are a lot of actions but two that you have interest to take into account:
. The only human behavior that you can control is yours,
. The only thing we can give someone is information.
« Fast and Furious 8 »
by F. Gary Gray

Molecular signaling means giving the right information in the right place for the best result:

Dependence at the heart of life

Any biological action within the human body requires the intervention of chemical compounds.

  • Calcium is compulsory for muscle contraction;
  • Growth factors are necessary for each cell division;
  • The immune response cannot take place without the recognition of the surface proteins of the major histocompatibility complex;
  • The nerve impulse is transmitted along the axon thanks to a local modification of the difference in ionic concentration.

The human body is a perpetual waltz of chemical reactions between diverse and varied molecules, dependent on each other.

Affinity is his motivation

These chemical compounds are found in solution or bound to a membrane or a complex structure such as the cytoskeleton, actin / myosin filaments…

When they are bound to the membrane:

  • They will act as receptors to detect extracellular chemical signals;
  • They will act as membrane transporters of ions or nutrients;
  • They will participate in the movement and the moving of the cell in response to stimuli.

When they are bound to the cytoskeleton or other complex structures, they will influence the shape of the cell and its expression.

When they are in solution, molecules will not have the same treatment depending on their size, their electrical charge and their chemical nature.

  • Hydrophobic molecules, oxygen, carbon dioxide, gases in general, steroid hormones, will diffuse freely in the cell;
  • Uncharged polar molecules, water, ethanol, urea, glycerol, amino acids, glucose can diffuse, but their diffusion will be slower and more difficult as their size increases;
  • The ions, and all the charged molecules will not be able to diffuse through the membrane, the membrane transporters will be compulsory.

Each stimulus, each encounter between compounds, a different expression occurs.

Affinity offers choice

The interaction of the compounds does not allow only punctual facts, but also allows malleability.

Take the example of axon growth:
The axon of neurons growths in the search for a target organ thanks to a growth cone.

  • The growth cone is a dynamic structure for exploring the environment;
  • It is very sensitive to the extracellular environment;
  • Thanks to its sensitivity to attractive or repulsive factors, it guides the axon towards the adequate target;
  • The relationship between membrane receptors, adhesion and the cytoskeleton is very important in this region;
  • When the axon reaches the target organ, there is accumulation of vesicles in the presynaptic region, and start of release of neurotransmitters;
  • The synapse is functional.

There are several hundred or even several thousand synapses per neuron, they are formed by learning and offer plasticity to the nervous system.

Let’s use the variability and the learning capacity of information to give meaning to our exchanges:

If we consider Humanity as a human body,
where each of Us is a chemical compound;

We can share our actions to bring good to Humanity as a whole;

Let’s humanize the World,
we will get the perfection of a healthy body.


Bibliographic references:
– The picture of axon growth is taken from the first year medical course.
– The information on molecular signaling is taken from the book « The Netter’s Anatomy Coloring Book », John T. HANSE, Elsevier Masson SAS, 2017 (the french version).

Cell adhesion, the force of the coherence

Exchanges cycle

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We can continue to divide ourselves with « I am right / you are wrong », thinking that there are many truths, or realize that the truth is unique, but we do not know it. Each of us has parts of it. To find the truth, let’s unite our views, let’s talk to learn what we don’t know but what the other has discovered.

The important thing is not to convince but to give to think about it.
Bernard WERBER

Cell adhesion, means making communicate specifically, different environments, as needed:

Perform a specific function

The heart,
it is not the liver.

  • The cell is the basic unit, structurally and functionally of all the tissues of the human body;
  • There are four basic tissues that are found throughout the human body:
  • The epithelial tissue: it covers the surface of the body, it delimits the cavities, it is the secretory contingent of the serous glands. It plays a barrier role, participates in exchanges, absorption and/or secretion, has the capacity to stretch and spread over expanding surfaces;
  • Connective tissue: it has a role of support, transport, storage, immune defense and thermoregulation;
  • Muscle tissue: it intervenes in the musculoskeletal system, causing movement, maintaining posture, changes in shape, and contributing to the movement of fluids in tissues and hollow organs. It forms the skeletal muscles, the heart muscle and the smooth muscles that line various organs and the walls of blood vessels;
  • The nervous tissue: it is at the origin of the central and peripheral nervous system.

The complexity of the structures makes possible, starting from basic element, to obtain a variability of functions.

An outside environment necessary for the inside environment

Just like water,
the membrane is necessary for life.

  • A cell can specialize for a particular function, thanks to its membrane which makes possible to obtain different environmental conditions inside and outside;
  • The extracellular medium will allow the supply of nutrients, chemical signals, and the removal of waste;
  • The intracellular environment will allow the realization of chemical reactions which will be at the origin of the reactivity of the body.

It is compartmentalization which provides the body, predisposed spaces to fulfill different functions.

The association is selective

Cell junctions show that the structure of associations
results in communication differences.

  • Tight junctions: There is a close rapprochement between two cells which does not allow any exchange between them; it is a barrier;
  • Open, communicating junctions: There is creation of a channel between two cells which allows the passage of small molecules; it is a sharing of resources;
  • The anchoring junctions between cells: There is creation of a plate between two cells which makes possible to give mechanical force to the tissues; it is a cohesion, a seal;
  • The anchoring junctions between cells and extracellular matrix: There is creation of a plate between a cell and the extracellular matrix, which makes it possible to feed the cell or to make it migrate for tissue repair; it’s support.

It is thanks to exchanges with the external environment, that the cell obtains the optimal conditions for living.

Let’s use the communicating nature of sharing to become aware of the Common Happiness:

If we consider that ideas are inside cells, and the world is the outside environment;

Junctions between our ideas can create a network of solutions;

Let’s decide to communicate together,
we will live Life in Peace.


Bibliographic reference:
– The information on the cell adhesion is taken from the book « The Netter’s Anatomy Coloring Book », John T. HANSE, Elsevier Masson SAS, 2017 (the french version).