Download ACP Level 2 Lesson Seven

ACP-2 Lesson Seven
Digestive System
A friend shared a story pertaining to her last gynecologist visit. She said while the doctor
was examining her, he found a benign obstruction in her bowel. She said he looked a
little puzzled at her because he couldn’t understand how that was affecting her
menstrual cycle. My friend, though, wasn’t surprised by this since she is an
aromatherapist and understood complementary medicine. The doctor finally concluded
after discussing it with her and said, “Pretty much every problem in the body, including
gynecology has at least some bearing on digestion.”
It’s about time traditional medicine caught up with complementary medicine! Now you
can see how learning about the digestive system effects every system in the body and
where healing begins.
The digestive system supplies the entire body with the nutrients it needs to function.
By changing the food into more easily absorbed substances, it enables the body to work.
We need these nutrients for growth, repair, heat and energy.
The juices inside of the stomach contain
proteins, calledenzymes, which help break down
food. When you take a bite of a delicious slice of
pizza, it travels a continuous route of almost 33
feet through the digestive tract.
It passes through the:
 Mouth
 Pharynx
 Oesophagus
 Stomach
 Small
Intestine
 Large
Intestine
 Rectum
 Anus
In addition to this tract, there are other organs
vital to the digestive process. These include:

Tongue

Teeth

Salivary Glands

Liver and pancreas.
So let’s take it from the top.
After you take your first bite of pizza, your salivary glands are activated as your tongue
begins to swish it around in your mouth. As the teeth start the process of breaking down
the food along with the saliva, its journey begins.
Let’s take a look at the teeth.
An adult has 32 permanent teeth. From the
front these are:

2 Incisors

1 Canine (or eye tooth)

2 Premolars or bicuspids
3 molars
Now, the tongue is another amazing
mechanism. It is made up of voluntary
muscle which is attached to the jaw.
Because the muscle is striated, it gives it
amazing motility to roll and twist as you
choose. The points of insertion of the
tongue are in the mandible (jaw bone) and also in the hyoid.

(Hopefully, all these terms are starting to come back to you from your high school or
college biology and/or anatomy class. Hyoid, point of insertion, striated voluntary
muscle….is it clicking yet?)
The little sensors on top of your tongue are
called papillae.
At the front or dorsum of the tongue
are the filliform


On the sides and tip are the fungiform
At the back of the tongue are the
vallate papillae, which are your taste
buds
Now if this is authentic New York style
Brick oven pizza, it should really be making
your mouth water. If you enjoy delicious
foods often, this may happen to you often.

Would you be surprised to know how many pairs of salivary glands there are…..only
three!

The parotid glands
(located in front and below the ears)

The submadible glands (located below the mandible)

The sublingual glands
(located under the tongue)
Here is an easier way to remember all
these special places on the tongue, lol.
We have a taste center for all
the palate favorites: sweet chocolate,
salty nuts,
sour
dill
pickles,
and dandelion greens!
To digest cooked starches, these glands
secrete
an
enzyme
calledplyalin.
Mastication or chewing passes the food
down the pharynx. This muscular tube has
seven openings.
These are:

Mouth

Oesophagus

Larynx

The two posterior apertures of the nose

Two auditory tubes from the ear.
Inside the pharynx uses an extremely efficient rippling effect to gently move food
through this tunnel down to the next stage of its journey, the oesophagus, and then
finally to the stomach. This rippling effect is called peristalsis.
For people who work out and have attained a six-pack, stomach shape will differ as
opposed to those who don’t, because muscle tone determines its shape.
Anatomically, the stomach is divided into
three sections:

The cardiac portion

The body
The pyloric
The cardiac
sphincter
muscle and
the pyloric sphincter musclesurround the
openings (Remember sphincters are circular
and open and close like an orifice?)

There are three outer layers of the
stomach. The middle layer is pure muscle. The inside is a mucous membrane lined with
glands which secretes gastric juices and the outer layer is a protective serous
membrane. This thin layer of cells that secretes serous fluid keeps it lubricated for
continuous movement. (Other examples of serous membranes you have already
encountered are pleura and the peritoneum.)
The gastric juices contain three main
enzymes:

Pepsin- for protein digestion

Rennin – which is what curdles milk
Hydrochloric Acid
The muscles of the stomach sac work
continually as you are probably very
familiar with the rather bizarre grumbles,
growls and pops it can sometimes make!
What you are hearing is the swooshing and
churning of the juices which are breaking
down your food and thoroughly mixing all of

the enzymes up.
As the food leaves the stomach, it travels onward to the small intestine. Up to this
point, the body has drawn no nutrients from the food. Its surface is rich with probes
which draw fats and sugars back down into the blood system. (Read that again and
memorize. Often exam questions will trick you by implying the stomach does the
work…remember nutrients come from the small intestine.)
The upper part of the small intestine,
the duodenum is the shortest at around
25cm or 10 inches long. Then curved like a
letter C is thejejenum measuring around
3.5m or 11 ½ feet long, then lastly
theileum, at 2.5m or 8 feet long.
The inner part of the intestine is all folded
and gathered. The stomach straightens and
extends as it works, but the folds of the
intestine do not disappear. This is
important because inside each fold is
mucous membrane completely littered with
tiny villi. These finger-like sensors probe the foods as it passes. As It comes into contact
with the lacteal,the fats are absorbed. Then as it touches the capillary loop, the sugars
and proteins are absorbed. The membrane also secretessuccus entericus from the
intestinal glands which also digests proteins and sugars.
In the ileum are found clusters of lymphatic nodules which are called Peyers
Patches which help to fight infection.
The ileum then merges with the wider large intestine. The name large
intestine pertains to its width rather than its length, because in fact it is only around
1.5m or 5 feet long. It snakes around the other internal organs and has nine different
sections.
The parts of the large intestine include:
1. Caecum
2. Vermiform appendix
3. Ascending colon
4. Traverse colon
5. Splenic flexure
6. Descending colon
7. Sigmoid colon
8. Rectum
9. Anus
The ileum opens out into the caecum. The illeo-caecal valve protects its opening and
ensures intestinal contents are able to traverse forward but have no way of flowing
backwards. Once the digestive juices have broken down the food, they are no longer
solid and so watery substances can pass through. It is common sense that some types
of food will take longer to process than others. Soup, for instance will be allowed to
pass through far more quickly than a piece of steak! An average meal will usually stay
in the system for about 4 hours.
At the closed end of the caecum is the vermiform appendix. This measures around 7.5
cm or 3 inches long. Passing up the right side of the body, the ascending colon then
bends hard to the left and becomes the transverse colon. It travels across the
abdominal cavity, then again, it turns left, and this juncture is called the splenic
flexure). As it continues down, this section is called the descending colon. From here,
it goes down the left side of the abdomen where it becomes thesigmoid colon. It now
enters the pelvic cavity and the rectum which measures around 13cm or a little over 5
inches long, then encounters the 2 sphincter muscles of the anus.
So, from beginning to end, we have covered the journey of your spicy slice of pizza
down the digestive tract or as it is sometimes called, the alimentary canal. So what
else is happening during this process?
The Liver
At this point you may want to revisit your lesson on Stress Physiology, because we talked
about how the liver is impacted by “The Fight and Flight Syndrome,” and how it has
to work overdrive to support the adrenals. Do you remember how it becomes exhausted
and begins to dysfunction? Okay then, let’s put that into context with what is happening
daily in your tummy. Ask yourself “What if it is not properly working…what would
happen with this bite?”
The liver is on the right hand side of the
body located just below your diaphragm. It
is the largest of the internal organs,
however, in actuality it is a gland. It
measures 25-30cm or 10 inches across and
is 15-18cm or 6 inches deep. It weighs
around 1.5kg or 3 ½ pounds in weight. It is
separated into left and right lobes. The
right lobe is further subdivided into the

Quadrate lobe

Caudate lobe
Here the main function of the liver is to manufacture and store bile.
About a litre or a quart of bile passes from the liver into the gall bladder every day. Its
job is to neutralize the stomach acids. In this pear-shaped sac bile is stored and further
concentrated until it is about 8-10 times the strength. When it reaches this strength, it
leaves the gall bladder and empties into the duodenum.
Simultaneously, there is a gland
which runs down the side of
the pancreas and
empties
pancreatic juices. The pancreas
is cream color and measures
about 15-20 cm or 6 inches long
and 4 cm 1 ½ inches wide. It has
4 parts:

Head

Neck

Body
Tail
From the lesson on the
endocrine system you may
recall
the Islets
of
Langerhans produce insulin in
the pancreas which is then
released
to
metabolize

carbohydrates.
Proteins in the system are broken down into the following building blocks:

Peptones

Polypeptides

Amino acids
Carbohydrates which may be starches or polysaccharides

Disaccharides

Then in turn Monosaccharide
Fats

Fatty acids

Glycerine
Consider then, the delicate balance between nutrients going to organs and glands, and
conversely how these would react if nutrition was not getting through. The liver
becomes overworked trying to keep up with the pace. It drains the HPA axis of
hypothalamus, pituitary and adrenals. Hormonal issues ensue,
And round and round it goes! It is a delicate cycle that we must maintain.