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?