Transcript Digestive System

Digestive System
Medical Terminology
Chapter 8
Structures of the Digestive
System
 The
major structures of the
digestive system include the
oral cavity (mouth), pharynx,
esophagus, stomach, small
intestine, large intestine, rectum
and anus.
 Accessory organs: liver,
gallbladder, and pancreas
Word Parts
 or/o
= mouth
 pharyng/o = pharynx
 esophag/o = esophagus
 gastr/o = stomach
 enter/o = small intestines
 col/o = large intestines (colon)
 an/o,
proct/o, rect/o = anus
and rectum
 hepat/o = liver
 cholecyst/o = gallbladder
 pancreat/o = pancreas
 -lithiasis = presence of
stones
 -pepsia = digestion
 The
digestive system - known
as the alimentary canal.
 The structures of the digestive
system are also described as
the gastrointestinal (GI) tract.
 (gastr/o = stomach, intestin =
instestines, al = pertaining to)
 Let’s start with the oral cavity,
or the mouth:
The Palate
palate – bony anterior
portion
 Rugae – irregular ridges or
folds in the mucous membrane,
covering the anterior portion of
the hard palate.
 Soft palate – flexible posterior
portion.
 Hard
The Tongue
gloss/o or lingu/o = tongue;
 upper surface has a tough
protective covering
 papillae are the ‘taste buds’
 underside of the tongue - highly
vascular; covered with delicate
tissue (easier to absorb some
medications)
 sublingual – under the tongue.

Terms related to the teeth:
– the natural teeth
 edentulous – without teeth
 primary dentition = baby
teeth; consists of 20 teeth.
 permanent dentition – 32
teeth; designed to last a
lifetime.
 dentition
Let’s do a quick survey…..
 Everyone gets an index card and
a red/green card.

 Using
your cell phones, text
one of each of these
questions to three different
people.
 You have 10 minutes to
obtain the answers.
 Write the answers down and
flip your card to green when
you have this completed.
 1.
What did you have for
breakfast?
 2.
What does the word
“gingivitis” mean?
 3.
How many times do you
brush your teeth each day?
Other structures….
– hangs down from the
free edge of the soft palate;
helps in producing sounds and
speech.
 gingiva – gums; specialized
mucous membrane that
surrounds the teeth, covers the
bone of dental arches, forms
the lining of the cheeks.
 uvula
The Salivary Glands
 The
salivary glands secrete
saliva that moistens food,
begins the digestive process,
and cleanses the mouth.
 3 pairs: parotid - on face in
front of and slightly lower than
each ear; sublingual – under
tongue: mandibular – on the
floor of the mouth.
The Pharynx
 the
throat
 common passageway for both
respiration and digestion
 During swallowing, the
epiglottis closes off the
entrance to the trachea, so that
food moves safely into the
esophagus.
The Esophagus
A
collapsible tube that leads
from the pharynx to the
stomach
 cardiac sphincter – at lower
end of esophagus; is a ring-like
muscle that controls the flow of
food between the esophagus
and the stomach; one-way.
The Stomach
 Has
three parts:
 fundus – upper, rounded part
 body – main portion
 antrum – lower part
– folds in the mucosa
lining the stomach.
 Glands within these folds
produce the gastric juices that
aid in digestion and mucus that
forms the protective coating of
the lining of the stomach.
 rugae
 The
pylorus is the narrow
passage connecting the
stomach with the small
intestine.
 The pyloric sphincter is the
muscle ring that controls the
flow from the stomach to the
first part of the small
intestine (the duodenum).
Small Intestine (enter/o)
 Consists
of three parts:
 Duodenum – first portion
 Jejunum – second portion
 Ileum – last portion
 The ileocecal sphincter
controls the flow from the ileum
into the cecum of the large
intestine.
Large Intestine (col/o)
 Extends
from the end of the
small intestine to the anus.
 The waste products of digestion
are processed in the large
intestine and then excreted
through the anus.
 Major parts of large intestine:
cecum, colon, rectum, anus.
The Cecum
A
pouch on the right side of the
abdomen; extends from end of
the ileum to the beginning of
the colon.
 Veriform appendix – hangs
from the lower part of cecum.
 Appendix serves no known
function in digestion; is
lymphatic tissue.
The Colon
 Subdivided
into 4 parts:
 ascending – travels up from
cecum
 transverse – passes
horizontally from right to left
 descending – travels down left
 sigmoid – “S” shaped; joins
with rectum.
Rectum and Anus
– last division of the
large intestine; ends at anus
 Anus – lower opening of
digestive tract.
 The flow of waste through the
anus is controlled by anal
sphincter muscles.
 Rectum
The Liver (hepat/o)
 Located
in RUQ of abdomen
 Functions: removes excess
glucose (blood sugar) and
stores it as glycogen. When
the blood sugar level is low, it
converts the glycogen back to
glucose and releases it for use
by the body.
 The
liver also destroys old
RBCs, removes poisons from
the blood, and manufactures
some blood proteins.
 Bilirubin – pigment produced
from the destruction of
hemoglobin, is released by the
liver in bile. Excess bilirubin is
associated with jaundice.
 The
liver secretes bile, which is
a digestive juice containing
enzymes that break down fat.
 Bile travels down the common
hepatic duct to the gallbladder,
where bile is stored.
The Gallbladder (cholecyst/o)
Pear-shaped sac located under the
liver. It stores and concentrates
bile for later use.
 The term cholecystic means
pertaining to the gallbladder.
 When bile is needed, the
gallbladder contracts, sending the
bile through the cystic duct and
into the common bile duct that
carries it to the duodenum.

The Pancreas (pancreat/o)
A
feather-shaped organ located
posterior to the stomach.
 It synthesizes and secretes
pancreatic juices.
 These juices are made up of
sodium bicarbonate (to help
neutralize stomach acids) and
digestive enzymes.
 The
pancreatic juices leave the
pancreas through the
pancreatic ducts that join the
common bile duct just before
entrance to the duodenum.
Digestion
 The
process by which complex
foods are broken down into
nutrients in a form the body
uses.
 Enzyme – responsible for
chemical changes that break
foods into simpler forms of
nutrients for the body to use.
– a substance, usually
from food, that is necessary for
normal functioning of the body.
 Six types of nutrients: water,
carbohydrates, protein, fats,
vitamins, and minerals.
 Each type of nutrient has a
specific purpose and meets a
specific need that your body
has.
 Nutrient
Water
 Yes, water is a nutrient. It is the most
important nutrient. In fact, your body is
approximately 50 to 55 percent water.
Your body uses water 24 hours a day.
A by-product of the energy production
in your body is heat. Water regulates
your body temperature by dissipating
that heat. Water also carries nutrients
to the cells in your body. Water does
not produce energy.

Carbohydrates are the primary source
of energy for your body.
Carbohydrates power every system in
your body, including your brain, heart,
muscles and internal organs.
Carbohydrates can be simple (table
sugar, corn syrup) or complex (whole
grain). Simple carbohydrates enter
your bloodstream very quickly. That is
why you get a sugar high when you
eat candy. Complex carbohydrates
are processed and used more slowly.
 Protein
 Protein
is like the brick and
mortar of your body. It is the
building blocks that provide the
structure for the tissues of your
body. Proteins are also used to
transport essential elements in
your blood stream.
Fats are our storehouses of energy.
When we have excess nutrients in
our body, some of it is stored as fat.
 The primary purpose of fat is
energy production. There are two
main types of fats - saturated and
unsaturated.
 Animal fats (meat, butter, lard) are
usually saturated fats and
contribute to heart disease and
cancer.

 Vegetable
fats (olive oil, corn
oil) are generally unsaturated
fats and are less harmful.
 Some fats have been found to
be helpful in preventing some
cancers and heart disease.
These fats called omega-3 fatty
acids are found in some fish,
especially cold-water fish.
 VITAMINS
 Vitamins
are essential for the
regulation of many of the
functions of the body.
 Most vitamins cannot be
manufactured by the body and
must be obtained from your
diet. Vitamins do not produce
energy.
Minerals are compounds, obtained
from your diet, that combine in
several ways to form the structures
of your body. For instance, calcium
is a mineral that is crucial in the
formation and maintenance of your
bones.
 Minerals also help regulate body
functions. Minerals do not produce
energy.
Metabolism
 Is
the sum of anabolism and
catabolism.
 The term “metabolism” includes
all of the processes involved in
the body’s use of these
nutrients.
– is the building up
of body cells and substances
from nutrients.
 catabolism – is the opposite of
anabolism. It is the breaking
down of body cells or
substances, and they release
energy and carbon dioxide.
 anabolism
Terms related to the
Digestive System:
– the rumbling
noise caused by the movement
of gas in the intestine.
 Gastroenterologist - specialist
who treats diseases and
disorders of the stomach and
intestines.
 Borborygmus
– involuntary grinding
or clenching of the teeth;
usually occurs during sleep;
assoc. with stress / tension.
 It wears away tooth structure,
damages periodontal tissues,
injures the temporomandibular
(TMJ) joint.
 Bruxism
– bad breath. May be
caused by dental diseases, or
respiratory or gastric problems.
 Dysphagia – condition of
difficult swallowing.
 Esophageal reflux or GERD –
the upward flow of stomach
acid into the esophagus.
 Pyrosis – heartburn. (pyro =
fever or fire)
 Halitosis
hernia – a protrusion of
part of the stomach through the
esophageal sphincter in the
diaphragm. This condition may
cause esophageal reflux or
pyrosis.
 Hiatal
ulcer – a lesion of the
mucous membranes of the
digestive system. Usually
caused by the bacterium
Helicobacter pylori ( H pylori),
and it may occur in the lower
end of the esophagus, the
stomach, or in the duodenum.
 Peptic
ulcer – peptic ulcer in
the stomach.
 Duodenal ulcer - peptic ulcer
in the duodenum. Is the most
common form of peptic ulcer.
 Perforating ulcer – involves
erosion through the entire
thickness of the organ wall.
 Gastric
 Eating
disorders:
 Anorexia – lack or loss of
appetite for food.
 Anorexia nervosa – refusal to
maintain a minimally normal
body weight and an intense fear
of gaining weight. Compulsive
dieting; excessive exercising.
– episodes of binge
eating followed by self-induced
vomiting or misuse of laxatives
or diuretics.
 Obesity – excessive
accumulation of fat in the body.
20-30% over the established
weight standards.
 Bulimia
– persistent eating of nonnutritional substances such as
clay.
 Eructation – belching
 Emesis – vomiting
 Hyperemesis – excessive
vomiting.
 Hematemesis – vomiting blood
 Pica
– a pouch or sac
occurring in the lining or wall of
the intestines.
 Diverticulitis – inflammation of
one or more diverticulum.
 Colorectal cancer – common
form of cancer that often first
shows up as polyps in the
colon.
 Diverticulum
– telescoping
of one part of the intestine into
the opening of an adjacent part.
This is typically found in infants
and young children.
 Volvulus - twisting of the
intestine on itself that causes
an obstruction.
 Intussusception
– another word for
intestine.
 Colonoscopy – the direct
visual examination of the inner
surface of the colon, from the
rectum to the cecum.
 Endoscopy – the examination,
using an endoscope, of the
interior of the esophagus,
stomach, and duodenum.
 Bowel
– a progressive
degenerative disease of the
liver, characterized by the
disturbance of the structure
and function of the liver.
Can lead to jaundice and
hepatic failure.
 Cirrhosis
– a test done to
detect blood in the stools.
 Hemoccult
Ostomies
 Remember,
an ostomy is a
surgical procedure to create an
official opening between an
organ and the body surface.
This opening is called a stoma.
 Examples:
– a new opening
into the stomach. This
procedure is frequently done to
place a permanent feeding
tube.
 Ileostomy – a new opening
between the ileum and the
abdominal wall.
 gastrostomy
– a new opening
between the colon and the body
surface. The entire segment of
intestine below the ostomy is
usually removed and a
discharge flows from the stoma.
It may be temporary or
permanent.
 It is named for the part of the
colon where the stoma is.
 Colostomy
 For
example:
 Colostomy (colon)
 Enterostomy (small
intestine)
 Duodenostomy
 Jejunostomy
 Ileostomy