Digestive System
Lecture 8
MACC Biology 101
Bill Palmer
Digestive System-General Functions
SecretionWaterAcidsEnzymes (proteins)
AbsorptionMovement into capillaries
ExcretionElimination of waste
Oral CavityFunction
Break food down by chewing and with enzymes in saliva
StructuresHard and soft palatesTongueSalivary glands
• Produce almost half a gallon (1.5 L) of saliva each day
Oral Cavity
Examples of lip and gum cancer -
Caused from smokeless tobacco
CopenhagenNow, I went out last Sunday with my little Mary-AnnShe said please stay still Monday, and grabbed me by my canShe laid a big one on me, surprised me with her tongue,But her surprise was waitin' there, between my cheek and gum.
Chorus:Copenhagen, what a wad of flavor.Copenhagen, you can see it in my smile.Copenhagen, do yourself a favor.Chew Copenhagen, drive them pretty girls wild.
So I went to the movies with my little Peggy-Sue,I had my dip there in my lip just like I always do.She didn't know that I was spittin' in my Coca-Cola cup,She took a great big swoller' and threw her popcorn up! Oh!
Chorus:The moral of this story is so very sad but true.If you stay 'till breakfast friend, they'll want to marry you.So try my little method and I promise you no doubtDip some Copenhagen if you want to snuff 'em out.
Oral CavitySalivary glands
Three Pairs• Parotid
• Sublingual
• Maxillary
Produce almost half a gallon (1.5 L) of saliva each day
Teeth
Permanent set consists of 32 teeth.Deciduous (“baby”) teeth are replaced starting at age five or six.
Third molars (“wisdom teeth”) may not appear until age 21.
upperdentalarch
hard palate
incisors(for cutting)
cuspid(for tearing)
premolars(for crushing)
molars(for crushing)
Pharynx and Esophagus
Pharynxfood, liquids, air
swallowing
EsophagusMuscular tube
0.8 in. diameter
Epiglottis closes trachea
Stomach
Expands
½ gallon
Functions
Temporary storage
Mixing
Secretion • Gastric juices• Mucus
Absorption
StomachProduces
Chyme
• thick semifluid mass of partly digested food that is passed from the stomach to the duodenum (beginning of the small intestine)
Small Intestine
Facts~ 20 ft long
80% of absorption occurs here
3 regions:• Duodenum
• Jejunum
• Ileum
Peristalsis-wavelike motion that moves material through small intestine
3 regions of Small Intestine
Duodenum• Receives chyme from stomach and secretions from
pancreas and liver (10 in.)
Jejunum• Region of most digestion and nutrient absorption (8
ft.)
Ileum• Absorption continues (12 ft.)
Pancreas
Exocrine (secretes externally) Digestive enzymes
Endocrine (secrete internally)Insulin (necessary for the body to be able to use sugar)
• stimulates a decrease in blood sugar levels
Glucagon• stimulates an increase in blood sugar levels
Diabetes-Two Types
Type IDiagnosed in children and young adultsbody does not produce insulin Controlled by diet and insulin injections
Type IIDiagnosed in older adultsbody does not produce enough insulin or the cells ignore the insulin can be precipitated by obesity or severe stress or menopause or other factors can usually be controlled by diet without injections of insulin
Diabetes-Emergency Treatments
Insulin ShockSubject may become faint and may pass-out
Occurs when diabetic takes insulin and then does not eat.
Too much insulin in system
TreatmentGive Sugar, Fruit juice, Candy-Anything with sugar for insulin to act on
Liver
Largest Internal Organ
FunctionsAids in metabolism
• substances are broken down to yield energy for vital processes while other substances, necessary for life, are synthesized.
Extracts nutrients
Filters toxins
Produces bile• aids in the emulsification, digestion, and
absorption of fats
Gallbladder
Muscular sac that stores bile
Gall stonesBile becomes too concentrated and contains too much cholesterol, hardens into crystals
Gall stones
Symptomssteady pain in the upper abdomen that increases rapidly and lasts from 30 minutes to several hours
pain in the back between the shoulder blades
nausea or vomiting
recurring intolerance of fatty foods
TreatmentPulverized with high-energy sound waves
Removal of gall bladder
Large Intestine
5 feet long
Holds and compacts undigested material
Absorbs water and vitamins
3 regions:Cecum
Colon
Rectum
3 regions of Large Intestine
Cecumlarge blind pouch forming the beginning of the large intestine. Also called blind gut
Colonextending from the cecum to the rectum Ascending, Transverse, and Descending
Rectumextending from the colon to the anal canal.
Diseased Large Intestine
Appendix
Vestigial Organ-little or no use
Left-over from plant eaters
May gather bacteria and other stuff and become infected-appendicitis
Can be removed without affecting the body
What do you think is the universal sign for choking is?
The Heimlich Maneuver
The sign for choking
is one hand grabbing the
the throat and the other
hand on top.
The Heimlich Maneuver
The Heimlich Maneuver
4 major steps
1.Check- check area
2.Check- check person
3.Call- get someone to call for help or yell help
4.Care- take care of person
Heimlich maneuver has two parts
• Back blows Lean person forward Using bottom of your hand give 5 back blows
aimed between shoulder blades
• Abdomen thrusts Get behind person Find belly button and go up 1inch Make fist and cover with other hand thrust up 5 times
Wrap-up
1. What are 3 parts of digestion system?
2. What is the function and location of: oral cavity, teeth, pharynx, esophagus, stomach, small intestine, pancreas, liver, gall bladder, large intestine?
3. What are the 3 regions of small intestine and their function?
4. What are gall stones? Symptoms? Treatments?
5. What are the 3 regions of large intestine and their function?
6. What are the two types of diabetes? When do they arise? In who? Why? Control?