Lesson 15: Cells, Tissues and Organs

 Lesson 16:  Tissue Anatomy Overview

   As explorers of embodiment, yogis will encounter myriad sensations emanating from all the layers of the body/mind. As we dive into the miracle of aliveness and attempt to communicate our experiences with ourselves, our students and the general public, it will be helpful to have a familiar 3 dimensional vision and language of the body. Cells and tissues are fundamental entities that begin our understanding of a living body. They combine to create organs, organ systems, and finally the fully integrated living organism.

The Cell

    The basic unit of life is the cell, which manifests in two basic forms, prokaryotic and eukaryotic. Prokaryotes lack a membrane bound nucleus, can use sources of energy other than oxygen, and, in the form of various bacteria and the recently discovered Archaea, compose the majority of single celled organisms on the planet. Eukaryotes, dependent upon oxygen, have a distinct nucleus as well as other membrane bound, differentiated structures such as mitochondria, lysosomes and vacuoles. They form the basis for all multicellular life forms including plants and animals. In the Quantum Biology section, we will look at a transformationally new model of cell structure and function that moves beyond the Newtonian “cell as a bag with stuff in it” concept. (Although the picture to the left can be useful!)

In multicellular entities, the cells are suspended in a complex fluid/connective tissue matrix somewhat like a sponge, and as we will see in Quantum Biology, the matrix is also suspended inside the cell. It is a continuum. This living matrix is crucial to the health of the cells and the organism and will be the primary focus of our explorations. This matrix performs several necessary functions. It allows the organism to maintain a dynamic 3 dimensional shape by channeling the forces of gravity and water pressure. It provides a support structure for the surrounding blood vessels and nerves which nourish and inform the cells. And it provides a flowing, fluid ground substance that acts as a resevoir to hold electrolytes, nutrients and other chemical messengers, and help transport cellular wastes away.

The human body consists of around 100 trillion eukaryotic cells, (and about 10 times that number of bacterial cells!), divided into about 210 different, specialized cell types, including cells that circulate throughout the body like blood and immune cells, cells that secrete various hormones, and cells that provide a lining to vesels and organs.


   The next order of complexity up from the cell is called tissue. A tissue is a collection of cells and associated intercellular materials which are specialized for a particular function. The human body is comprised of four categories of tissue: nervous, muscle, epithelial, and connective. These tissues are used in different proportions and arrangments to create the more complex organs. An organ is a group of tissues designed and organized to perform a particular function or group of functions such as the heart or the liver. Several organs can work together to form organ systems such as the cardiovascular, urinary, or reproductive systems. The living matrix interpenetrates all levels of cells, tissues, organs and organ systems and is the individual embodiment of what Buddhist teacher Thich Nhat Hanh refers to as interbeing, the realization that all of us are enmeshed in a web of interconnected relationship.

Nervous Tissue

Nervous tissue can be considered either central (brain and spinal cord) or peripheral (nerves). It is composed of two major types of cells: nerve cells or neurons and glial cells. Neurons are the cells that carry out the essential function of nervous tissue: communication. They are the primary structural and functional unit of the nervous system and are specialized for sending signals rapidly over long distances to other cells. Neurons have a wide variety of shapes depending on their location and function. Different parts of the neuron are specialized for different tasks. Dendrites, and each cell can have many, receive information for other nerve cells. Axons, only one per cell, send information. Neurons have the capacity to react to various physical and chemical stimuli (irritability) and the ability to transmit the resulting excitation from one locality to another (conductivity).

Glial (glue) cells make up ‘The Other Brain’ as described by R. Douglas Fields in a book of the same name. Totally different from neurons, glia have their own communication network, insulate and support the neurons and even regulate the flow of information between neurons. They also provide nourishment and other aids to neuron function. Glia come in a wide variety of shapes and sizes depending on the particular type and the study of them is one of the more exciting explorations on the frontiers of brain science.

Muscle tissue

Muscle tissue has specialized, elongated contractile cells that perform their functions by developing a tension along their longitudinal axes. Specialized proteins, actin, myosin and troponin, allow the cells to shorten and lengthen and their ability to contract provides a mechanism for movement of the internal organs and locomotion of the entire organism.

Groups of muscle fibers may form fasciculi (fasciculus = small bundle), and many fasciculi, in turn, are aggregated into units we call muscles. There are 3 major types of muscle tissue: skeletal, cardiac and smooth. Skeletal muscle is attached to bones. Cardiac muscle is found in the heart. Smooth muscle is found in vessels, ducts, skin, and internal organs. Muscle tissue is may be controlled by nerves, hormones, local chemicals, or itself depending on the type and location.


Epithelial tissue

There are various types of epithelial tissue with cells that are often arranged in sheets. This tissue covers all internal and external body surfaces, lying on a basement membrane which serves to anchor the cells. All materials that enter or leave the body do so through an epithelial membrane and thus some fundamental functions of epithelia include protection, absorption and secretion.

Epithelia are classified according to the shape of the cells (squamous, cuboidal,or columnar) and the number of layers (simple, stratified,or pseudostratified). A special type of epithelium, endothelium, makes up the walls of blood and lymph vessels. Another, transitional, is found in the bladder and ureterswhere it can expand and contract. Epithelial tissue is nourished by diffusion from blood vessels situated in the underlying connective tissue as no blood or lymph vessels are found in epithelium.

Epithelial tissue can produce downgrowths into underlying connective tissue called glands and contain cells whose functions are secretion and excretion. There are two main types of glands, exocrine glands and endocrine glands.

Exocrine glands possess ducts which convey the secretory material (mucus, enzymes, etc.) to the surface of the body or cavity lined by the epithelium. Endocrine glands have lost their connection to the epithelial lining from which they were derived and therefore lack ducts. These clumps of cells release their secretions (hormones) directly into the bloodstream, where they are distributed throughout the body.

   Classification of glands can be very confusing and is based on branching of the ducts (simple vs compound), shape of the secretory region (tubular, alveolar, tubuloalveolar) and by the type of secretion (mucous, serous or mixed).


Connective Tissue

  In biology, the extracellular matrix (ECM) is any material part of a tissue that is not part of any cell. Extracellular matrix is the defining feature of connective tissue. There are five different types of connective tissue: blood, bone, loose, dense and cartilage. Connective tissue connects, holds and supports other body tissues and cells and consists of three major components: cells, extracellular fibers and extracellular ground substance.


Connective Tissue Cells

  Cells which inhabit the connective tissues provide defense as well as produce the supportive structures. Some cells remain in the connective tissue and function in its long-term maintenance. Examples include: fibroblasts
which are responsible for the formation of collagen, elastin and ground substance that comprise the extracellular component of connective tissue: mesenchymal cells (embryonic connective tissue cell commonly called stem cells) and adipose or fat storing cells.

Other wandering cells enter the connective tissue in response to injury or invasion by microorganisms. Examples include mast cells, antibody secreting plasma cells and the trash collecting macrophages. Mast cells are widely distributed in connective tissue and are particularly abundant along small blood vessels. They contain many granules whose contents are responsible for preventing blood clotting and increasing the permeability of capillaries and venules, thus allowing other cells to enter the connective tissue from the blood to fight foreign invaders.

Extracellular fibers, secreted by the fibroblasts, give connective tissue its strength. There are three types: collagen fibers are composed of the protein collagen. They have great tensile strength and are inelastic. Reticular fibers are very thin collagen fibers and form delicate networks around blood vessels, nerves and certain other cells. Elastic fibers are composed of the protein elastin. They stretch easily but return to their original length. They are most abundant in tissues that require flexibility, for example, the ligamentum nuchae on the back of the neck.

Ground substance is the name for the amorphous, gel-like intercellular material in which the cells and fibers of connective tissue are embedded. It is composed of water, proteoglycans (large molecules which help store and regulate the movement of ions and water), other plasma constituents, metabolites and ions, and functions as a medium through which nutrients can diffuse from blood vessels to nourish the cells and the waste products can diffuse back into the blood stream.

Types of Connective Tissue

  Blood is a fluid connective tissue in which cells are suspended in a fluid matrix called plasma. Plasma is composed of water, protein and other solutes. Blood cells include erythrocytes (red blood cells), leukocytes (white blood cells), and platelets.

   Loose Connective Tissue has an abundance of cells and ground substance, but relatively few fibers. It is soft and pliable and serves as a kind of packing material between other tissues and organs. It is found between muscles, allowing one to move freely over the other and supports small blood vessels, lymphatic vessels and nerves. When filled with fat cells, it is known as Adipose Tissue.

   Dense or Fibrous Connective Tissue has a greater proportion of fibers, fewer cells and less ground substance than loose connective tissue. There are four types of dense connective tissue; fascia, tendons, ligaments, and aponeuroses. We will take a closer look at fascia in a moment.

   Cartilage is a form of connective tissue that is much firmer than dense connective tissue. It consists of a dense network of fibers embedded in a gel-like intercellular material which confers firmness but also permits flexibility. The cells of cartilage are called chrondrocytes. Cartilage has no blood vessels and the cells are entirely dependent on diffusion as the source of their nutrients and oxygen. There are three basic types of cartilage that serve different functional requirements and vary by the type of fiber embedded in the ground substance.

Elastic cartilage has a large number of elastin fibers, allowing it to be very flexible and when deformed, able to immediately return to its normal position. It is found in the auricle of the ear.
Hyaline cartilage, the most widely distributed type of cartilage found in the body, has very little elastin and mostly collagen. This hard, translucent tissue first appears first as the developing bones in the embryo. As growth continues, the cartilage tissue is gradually replaced by bone tissue. At maturity, hyaline cartilage remains at the end of bones where they articulate with one another. Hyaline cartilage also supports the nose, larynx, trachea and bronchi of the respiratory system.
Fibrocartilage is the most abundant cartilage by weight. It is a both tough and elastic tissue present in regions of frequent stress. Containing both elastin and collagen, fibrocartilage is found in the intervertebral discs, the menisci of the knees and the pubic symphasis.

Bone is the most rigid form of connective tissue and is much firmer than cartilage. The hardness of a bone (equal to that of cast iron!) is caused by the presence of calcium phosphate; the small degree of elasticity possessed by bone is caused by the presence of organic collagen fibers. The cells of bone are called osteocytes. Unlike cartilage, bone contains small tubular canals through which the cells are nourished. Bone exists in two forms: compact and spongy.


Fascia, one of the three types of dense connective tissue, is located between the skin and the underlying structure of muscle and bone, and is a seamless web that covers and connects the muscles, organs, and skeletal structures in our body. It consists of three layers: the superficial fascia, the deep fascia and the subserous fascia. Muscle and fascia are united forming the myofascial system, the focus of attention in the body work systems operating under the umbrella of structural integration and including Rolfing and Kinesis Myofascial Integration.

The Superficial Fascia is located directly under the subcutis of the skin. Its functions include the storage of fat and water and it also provides passageways for nerves and blood vessels. In some areas of the body, it also houses a layer of skeletal muscle, allowing for movement of the skin.

The Deep Fascia is beneath the superficial fascia. It aids muscle movements and, like the superficial fascia, provides passageways for nerves and blood vessels. In some areas of the body, it also provides an attachment site for muscles and acts as a cushioning layer between them.

The Subserous Fascia is between the deep fascia and the membranes lining the cavities of the body. There is a potential space between it and the deep fascia which allows for flexibility and movement of the internal organs.

for more information:


http://mywebpages.comcast.net/wnor/ (on line anatomy course with great visuals!)



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Micro-Cosmic Orbit: Pt 2

Exploring and Embodying Three Dimensions

In the previous post we explored the micro-cosmic orbit as a means to refine our focal attention (samadhi) through bringing our attention to specific points along the orbit and linking these points into lines, arcs and circles. As we work more deeply this way, we may discover that we can find these points at three levels. The first is out beyond the confines of the skin, in an ‘orbit’ in the energy field around the body. The second is directly on the skin, where an acupuncturist or shiatsu practitioner would apply needles or pressure. The third is in the interior of the body along the planes of fascia interwoven through the organs, blood vessels and nerves. When we can feel all three of these levels simultaneously, we are inhabiting our spherical energy field and can begin to fully realize the possibilities of having three dimensional/spatial sensitivity, perception and consciousness.

images-5The girdle vessel (Dai Mai,) the fourth vessel we use, is a latitude line and is essential in finding our three dimensional perceptual field. This yang vessel pairs with the yin ‘thrusting vessel, the vertical center axis, creating horizontal stability, and allowing us to rotate/twist. Rotation inherently builds the third dimension of depth ( A circle has length and width. To create a sphere you add depth. ) and is the gateway to cosmic awareness as well as a more vibrant embodied presence.

Rotation drives the whole manifest universe. In our solar system, the planets spiral around milky_waythe sun. In our Milky Way galaxy, the stars, including our sun, spiral around a center (probably a giant black hole! If you can find Sagittarius in the night sky, and you will probably have to wait until next summer, look through and imagine 26,000 light years off in the distance.) The earth rotates on its own axis creating weather patterns as well as a sense of day and night.

The spinning top (one of the oldest toys known to humans, found in archeological sites all over the world) demonstrates the cosmic principle in physics we are embodying. The faster it rotates, the more stable the vertical line. When the top slows down it starts to wobble and when it stops spinning, it falls over. To keep the rotation, you need to keep feeding it with energy. The bicycle uses this same principle, flipped 90 degrees. Another aspect we explore is the radius of the horizontal circle. Rotation pushes from the center outward (yang) in what is called centrifugal force. As this is counterbalanced by theGM2434B-1 yin centripetal (center seeking) force, we can change the volume of the energy field by playing with this ‘expanding – condensing’, yang – yin relationship.

In this top, the widest circle with the most outward thrust, the purple one, is below the center of the vertical axis. Lowering the center of gravity adds even more stability, which is why we emphasize the lower dantien in our breathing, movement and meditation practice. When we discover how to work with this principle in the energy field, our twisting poses can actually help expand the body. If we work muscularly, you will feel constricting in twisting poses.

SBK_1711254-24Traditionally the ‘dai mai’ girdle vessel surrounds the body at the level of the pelvis in the lower dantien. but we can move our attention to awaken other ‘latitudes’ of the body. To begin in the feet, stand with the right foot forward, the left foot back, as if you are about to move into a standing twist (without the forward bend), but haven’t yet begun. Before you move any further, imagine a spiraling coil of energy beginning below the floor (the Antarctic Circle) and traveling up the center. Notice how this mimics the girdle vessel. Now imagine the coils widening as they rise up from the base ( moving toward the equator), as the yang energy expands outward. The girdle vessel is very yang so this is quite natural. Feel the energetic volume expanding and condensing with the breath, but slowly expanding in overall volume

To awaken the front body-yin energy field, we can take the hoop forward to fully engage the arms and shoulders. Now imagine the hoops extends through the back body, receiving the rising spiral and expanding as the action of twisting. SBK_1711254-2SBK_1711254-9Most students eventually leave half of the body behind and end up contracting rather than expanding, especially along the spine column. Imagine the center of the spinal canal opening outward in an expanding circle/spiral, melting the tissue, feeling spaciousness, transcending the limitations of structure.SBK_1711254-4 (My front foot turns out much more than average to release the inner groin. Don’t feel you have to imitate this, but find out for yourself where openness and balance meet.) The hoop is moved to the front to expand the yin/organ/front body qi field and expand the ‘wings’ of the body, but also feel the back body softening and opening. This feeling can be evoked in sitting, lying and inverted twists as well. If you do not have a hula hoop handy, you can also use a thera-ball to find the volume.SBK_1711254-8


Another key component awakened here is the Pericardium 8 point, PC-8 (or P-8) in the center of the palms. Analagous to the K-1 points on the feet, P-8 is a gateway between the inner and outer qi fields. The SBK_1711254-11Pericardium, the fascial connective tissue membrane surrounding the heart, arises embryologically from the same cells and tissues that create the diaphragm and liver. The ‘heart protector’ literally does this, on many levels. As someone with a well-armored heart, I am finding that opening and nurturing the heart protector so that is does its job with over doing it is awakening a level of sweet vulnerability that is both precious and scary.

SBK_1711254-12In acupuncture, the pericardium meridian is part of the JueYin channel and connects all the way through the femoral canal to the legs. For those of you who have been practicing ‘climbing the wall’ for the last few years, you can actually trace the whole fascial continuity of the Jue Yin. (Use imagination to fill in the blanks.) Rise up from K-1 (not the heels, even though they do rise on their own) (DFL for those of you who know Tom Myers’ ‘Anatomy Trains’ system) to P-8, passing through liver, diaphragm and pericardium.

You can also track the qi from P-8 back into the body horizontally, again using the wall.SBK_1711254-14 Using the tip of the  middle finger of your other hand (PC-9) to feel the connections, trace the qi from the the wall and P-8 into the area around the pec minor muscle and then go inside the body to the pericardiam itself, along with the liver and diaphragm. Use the breath and your imagination. Then go back and try the twistings shown above with these new perceptions.

SBK_1711254-20To continue our building of a three dimensional perceptual qi field, we can return to the thera-ball to provide sensation and visualization. I like the feel of my third chakra having organ support, so I find placing the ball there and using a wall creates a powerful presence on the inside. Embryologically speaking, this is the extemely yin yolk sac which becomes the entire gut body. The conception vessel points on the micro-cosmic orbit are stimulated by the ball, bringing sensation and perception here. The liver comes from the yolk sac, so I can use this position to also find the Jue Yin channel we explored above. Lying SBK_1711254-19over the ball in a forward bend creates a similar feeling, with even more yielding and softening to the yang back body erector muscles. By moving the ball to the sternum, I can activate a new set of points on the conception vessel and engage the inner tissues surrounding the 4th chakra

If I want to build up my back field perception, I use the ball from behind and awaken sensation on the yang Governing Vessel.SBK_1711254-16 Here I have dropped it a bit lower to find the sacral-lumbar junction and here I can feel the possibility of both lumbar flexion and extension, from S curve to C curve and back.  The very important GV-4 Qi gong Image‘gate of vitality’ is here The inner abdominal space also opens and the front back and center plane begin to become conscious. This becomes trickier as you move upwards towards the liver. You can place the ball anywhere and feel different points coming alive. Feel their inner as well as outer presence. Back support can also help open the front. I haveSBK_1711254-17been trying to open my throat more for my sax sound and using the ball (or any elastic support) helps soften and melt tight tissue.

SBK_1711254-21Fish body support, opening some Gall Bladder Meridian points is another way to use the ball. I am using the wall, but this can be done on the floor as well, with slightly different effects. All of these ways of playing with the three dimensional field are ways of awakening and establishing a dynamic energetic field, centered in your heart, and radiating out throughout the whole of the cosmos. When you are out in Nature, feel this. When you are out and about in the human sphere, feel how you respond. It is fascinating to see what happens.

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