Transcript Digestion - davis.k12.ut.us

The Digestive System
Maintenance Systems
Unit 7
Standards and Objectives
05.01 Describe the basic functions of the digestive system:
ingestion, digestion, absorption, and excretion.
05.02 Describe the basic functions of the digestive organs
(mouth, pharynx, esophagus, stomach, small intestines, large
intestines, rectum, and anus) and their role in digestion.
05.03 Describe the diseases and disorders of the digestive
system: colon cancer, Crohn’s disease, celiac disease,
appendicitis, and inguinal hernia.
05.04 Recognize levels of education, credentialing
requirements, employment opportunities, workplace
environments, and career growth potential for the following
careers relating to the digestive system: dentist, dental
assistant, dental hygienist, dietitian, and central services.
Vocabulary
• Mastication - chew: biting and grinding food in your
mouth so it becomes soft enough to swallow
• Emulsification – (in digestion) The breakdown of fat
globules in the duodenum into tiny droplets, which
provides a larger surface area on which the enzyme
pancreatic lipase can act to digest the fats into fatty
acids and glycerol.
• Deglutition – the act of swallowing
• Peristalsis – involuntary relaxation and contraction of
a tubular organ to allow contents to move through.
The Basic Functions of the Digestive System
• Ingestion-taking nutrients into the body, i.e.,
eating
• Digestion-the mechanical and chemical
breakdown of food into a usable form
• Absorption-the movement of molecules
through the mucosal lining of the stomach
and small intestine, and into the blood
• Excretion-the removal of solid waste from the
body
• Sphincters-circular muscles that contract and
move food through the GI tract.
The Digestive Organs
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Mouth
Pharynx
Larynx
Esophagus
Stomach
Small Intestines – 3
duodenum, jejunum, ileum
• Large Intestines – 4
ascending, transverse, descending, sigmoid
• Rectum
• Anus
Mouth
Digestion starts here!!!
• Mechanical digestion-chewing or
“mastication”
• Chemical digestion-digestion of
carbohydrates
Teeth
Enamel – hard, white covering protects tooth from wear
and tear of chewing. The hardest substance in your
body.
Dentine – below the enamel, it is the yellow bone-like
material that is softer than enamel and carry some of
the nerve endings.
Pulp – is the center of the tooth. It contains blood
vessels and nerves. Where the tooth receives
nourishment
Cementum – covers root of tooth, attaches tooth to the
bones in the jaw.
Pharynx
• Also called the throat
Nasopharynx
Oropharynx
Laryngopharynx
• A passageway for food, liquids, and air
Esophagus
• Muscular tube located behind the trachea
• About 10 inches long
• Transports food from the pharynx to the
stomach
• Upper and Lower esophageal sphincters
Stomach
• J-shaped pouch located below the
diaphragm
• Chemical digestion of protein occurs in
the stomach due to gastric juice secretion
• Mechanical digestion occurs in the
stomach due to maceration (churning).
Three layers of muscles in the stomach
create the movement of maceration.
Liver
• Largest organ in the body
• Liver has many jobs
– Changing food into energy
– Cleaning alcohol and poisons from the
blood
– Creates Bile, a yellowish-green liquid that
helps with the digestion of food.
Gallbladder
• Structure on the underside of the liver
• Function of the gallbladder is to store
bile that is produced in the liver
• Bile is secreted into the intestines to help
with the emulsification of fats.
Small Intestines
•
Chemical digestion of nutrients and
absorption of nutrients is completed in the
small intestines
Three divisions of the small intestines:
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Duodenum – first portion of the small intestine
where the majority of chemical digestion occurs.
Jejunum – middle portion of the small intestine
where the majority of absorption of nutrients
occurs.
Ileum – final portion of the small intestine where
absorption occurs.
Large Intestines
• The large intestines are the last part of
the digestive system.
• Absorption of water, vitamins,
electrolytes, production of vitamin K,
and formation of feces occurs in the
large intestines
• Ascending, Transverse, Descending,
Sigmoid colons
Rectum
• The last portion of the large intestine
which functions as a temporary storage
of solid wastes before excretion
Anus
•
The final portion of the rectum where
solid waste is excreted from the body
Diseases and Disorders of the
Digestive System
Colon Cancer
• Most of the cancers of the large intestine are believed
to have developed from polyps (benign tumors).
• Cancer of the colon and rectum, also called colorectal
cancer can invade and damage adjacent tissues and
organs.
• Symptoms include fatigue, weakness, shortness of
breath, change in bowel habits including diarrhea or
constipation, red or dark blood in stool, weight loss,
abdominal pain, cramps, or bloating.
• Surgery is the most common treatment for colon
cancer.
• Quick Write: Who is more likely to get colon cancer,
men or women?
Crohn’s Disease
• Chron’s disease is an ongoing disorder that causes
inflammation of the digestive tract.
• The disease can affect any area of the GI tract, from
the mouth to the anus, but it most commonly affects
the lower part of the small intestine, the ileum.
• The swelling extends deep into the lining of the
affected organ.
• The swelling can cause pain and can make the
intestines empty frequently, resulting in diarrhea.
• Chron’s disease may be caused by an abnormally
functioning immune system.
• Treatment includes prescription medications,
nutritional supplements, surgery, or a combination of
these.
• There is no cure.
Celiac Disease
• Celiac disease is a digestive disease that damages the
small intestine and interferes with absorption of
nutrients from food.
• People who have celiac disease cannot tolerate a
protein called gluten, found in wheat, rye, and barley.
• When people with celiac disease eat foods or use
products that contain gluten, their immune system
responds by damaging the small intestine.
• Celiac disease is an autoimmune disease that is
genetic.
• The most common symptoms include pain in the
digestive system or other parts of the body.
• The only know treatment is a gluten-free diet.
Appendicitis
• Appendicitis, inflammation of the appendix, is
the most common surgical disease.
• It results from the obstruction of the opening
to the appendix by a mass, structure or
infection.
• Symptoms of appendicitis include generalized
abdominal pain, pain localized in the lower
right abdomen, nausea, vomiting, possibly
fever, and an elevated white blood cell count.
• Treatment involves the removal of the
appendix and antibiotics.
Inguinal Hernia
• Inguinal hernias occur when a part of the
intestine protrudes through a weak point or
tear in the abdominal wall.
• This protrusion creates a buldge which can be
painful.
• Some inguinal hernias occur at birth when the
abdominal lining does not close properly.
• Other inguinal hernias occur later in life when
muscles weaken or deteriorate.
• The most common treatment is surgery.
Careers
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Dentist
Dental Assistant
Dental Hygienist
Dietitian
Central Service Technician
Proctologist
Dentist
• Doctor who study, diagnose, treat and
prevent diseases and disorders of the oral
cavity.
• Undergraduate degree plus four years of
dental school
• $60,000 to start – over $100,000/yr is
common after a few years of practice.
Dental Hygienist
• Teach patients oral hygiene, providing
preventive dental care, examination of
patient gums and teeth and recording
oral problems as well as cleaning teeth.
– Some states they can give local anesthetics
by use of syringe, perform filling
procedures, and remove stitches.
• Education – 4 years
• Salary - $74,000/yr
Dental Assistant
• Help with office services such as
scheduling appointment, updating
patient files, setting up tool packs for
dentist or hygienist.
• Education – less than 12 month dental
assisting course.
• Salary - $33,000/yr
Dietician
• Help others to develop and maintain a
healthy diet. Can work in a variety of
settings such as: hospitals, health care
facilities, schools, and government
agencies.
• Education – Bachelor’s degree and state
licensure or certification.
• Salary - $50,000/yr
Central Services Technician
• Clean medical instruments, assemble
surgical trays and examine medical
equipment for repairs.
– AKA central sterile supply technicians and
medical equipment preparers.
• Education – technical school or
community college, less than 6 months.
• Salary - $30,000/yr
Proctologist
• Field of internal medicine that aims to
prevent diseases and disorders of the
colon, rectum and anus through
preventative medicine and treatments.
• Education – 4 years undergraduate plus
4 years of medical school and 6 years of
residency as a proctologist and surgeon.
• Salary - $200,000/yr