1. Motility (moving stuff along)

 -Perstalsis

-segmentation

2. Secretion- addition of digestive enzymes,etc.

3. Degestion- biomechanical breakdown of food using hydolysis

-CHOs frm starches/glycogen --> monosaccarides

-Protiens --> polypeptides and amino acids

-Trigycerides --> glycerol and fatty acids

4. Absorption- From digestive tract into blood or lymph

Digestive sytem consists of

• A tract
• accessory organs

• -continuous tube from oral cavity to anus

       -the lumen of the tube is continuous external environment (donut)

• accessory organs-salilaryglnds, exocrine glands, and biliary system(liver and gallbladder)

1. Mucosa

-lamina propria- colligan,aereolar

-GALT(Pier Patches, immune sytem)

-musculari mucosa

2. Submucosa-shape(CT)

3. Muscularis externa

-inner circular layer, outer longitudinal layer

-myeteric plexis-nerve/control

4. Serosa

-continuous with mesentaries (holds things in place)

-aereolar

1. Autonomous smooth muscle function:

-autorhythmicity-depol on own but not agrigated

-Slow wave potentials

2. Myenteric plexus & Sumucous Plexus (ag. of autonomic nervous system)

-effected by para and sympathetic signals from the nervous system.

3. Edocrine glands-release hormones that signal digestive response

4.receptors-chemo(ph, protien/lipd content),osmo (water and ions),and mechan(strech)

Oral Cavity

-mechanical digestion-mastication

-No nutrient absorbtion

• Three pairs of glands in oral cavity
• Three important element found in saliva and their function

• Subligual,Submandible,Curotid
• Salivary amylase (carb/starch bd), Ligual lipase (lipid bd), lysozymes (anti bacteria)

-Motility(associated with the pharynx and larynx)?

-Preventions of choking

 -Peristalisis

-Swallowing -food hit receptors, motility starts voluntary-->reflex 

-apnea,epiglotis

-movement of bolus through esophagus due to CLC contractions

Stomach

-sections?

*secretions?

Cardia-protect, Fundus-give space so stomach can mix, Body-storage mixing,plyloric-HCl and chemo receptors

*secretions include pepsin-protien breakdown and HCL to process bolu into chime

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Stomach Motility

• filling
• storage
• mixing
• emptying

• filling-little strech due to rugae
• storage-in the body of the stomach
• mixing- secretions w/bolus to form chime, peristalic waves       
• emptying- controlled by pylorus(amt and viscosity of chime) and duodennum(can slow down gastric emptying- neural reflex by stretch receptors & hormonal reflex induced by PH or fat content-->releases secretin and cholecytokinin (cck)that act on stomach cells)   

Gastric digestive juice is secreted by glands located in the base of the gastric pits.

• Mucous cells
• Cheif cells
• Parietal cells
• Stem cells

• thin watery mucous
• pepsinogens
• HCl-breakdown of CT and muscle fibers, killing of most micro organisms,pepsin formation
• replacement of Gastric mucousa

The control of Gastric secretion involves three phases

• cephalic
• gastric
• intestinal

• Cephalic- stimuli from brain and mouth increase HCl and pepsinogen secretion
• Gastric-stimuli in stomach initiate gastric secretion, increased stimulus by caffeine and alcohol
• Intestinal-inhibitory, shuttting off the flow of gastric juices as chyme  enter the duodenum

Other facts about the stomach

-CHO and lipd digestion begin in mouth and continue in the stomach until PH drops below 4

-Protein digestion begins in stomach due to pepsin when Ph drops below a 2

-No food or water is absorbed in stomach but alcohol and aspirin can be.

The small intestine is where most of digestion and absorbtion occur

• three segment of the small intestine?
• rapid ______ and slow ______ occur
• ileocecal juncture prevents comtamination of the small intestine by colonic bacteria (ie.Pier patches)

• Duodenum,jejunum,ileum
• segmentation, peristalisis

Small intestines

-do no secrete digestive enzymes, ____ and ____ do.

-molecule produced by digestion enter either the ________ or ________ vessel. ---> sorted by the liver, controls nutrients concentration in blood

-absorbtion doesnt usually happen based on the bodies need but concentration gradient.--eceptions to this are

-liver and pancreas

-lymphatic or capillary

-Iron and Calcium (active trans after cons if full)

Large intestine-mainly drying and storing organ

• consists of cecum, colon,appendix, and rectum
• Taeni coloni is the muscle that helps form postra pockets allowing for segmentation --controled by___
• defication-occurs?due to?

• intrinsic plexi
• 3 to 4 times daily-due to gastrocolic reflex mediated by gastrin release when food enters stomach.

Feces are eliminated by the defication reflex

• internal anal sphincter
• enternal anal sphincter
• colon contains benificial bacteria include making vitamin K and enhancing intestinal motality

• internal- involuntary smooth muscle
• external-voluntary skeletal muscle

Pancreas contain exocrine and edocrine cells

• secretes wich three digetive enzymes?
• Secretes alkaline fluid wich acts as a ______?
• CCK regulate exocrine secretion and secretion of digestive enzymes. Secretin also regulatesexocrin secretion

• proteolytic,pancreatic amylase,panccreatic lipase
• Buffer
• amylase-converts starch to disaccharides
• lipase-hydrolyize dietary lipids

• process and sort nutrients
• detoxifies body waste
• synthesizes plasma protien
• store stuff-fats
• activates v D
• removes bacteria and some worn out RBCs
• excrete bilirubin and cholesterol
• hepatic portal
• common bile duct liver -->duodenum
• bile stored in gallbladder during meals...released through sphincter of oddi

-breakdown proteins

- not a component of silivia

1)             Which of the following is entirely under nervous control and has no hormonal regulatory component?

a.     Salivary secretion

b.     Gastric secretion

c.     Pancreatic secretion

d.     Liver secretion

e.     All of these answers have a hormonal regulatory component

1)             Which of the following breakfasts would remain in the stomach the longest?

a.     Toast, orange juice, and coffee

b.     Black coffee

c.     Fried eggs, bacon, and hash browns

d.     Bowl of cereal and skim milk

e.     Boiled egg, toast, and juice

20) The parietal cells of the gastric mucosa secrete:

a. HCL

b. Pepsinogen

c. Intrinsic factor

 d. Gastrin

e. Both A and C above

1)             Which statement regarding control of pancreatic secretion is CORRECT?

a.     Gastrin stimulates release of neutralizing solution

b.     CCK stimulates release of enzymes

c.     Secretin stimulates release of bicarbonate

d.     Both A and B above

e.     Both B and C above

1)             Which of the following enter the duodenum?

a.     Pancreatic secretions

b.     Bile

c.     Chyme

d.     Both A and C above

e.     All of the above

1)             The defecation reflex:

a.     Is initiated when mass movements force fecal material into the rectum, stimulating stretch receptors in the rectal wall

b.     Involves relaxation of the internal anal sphincter and contraction of the sigmoid colon and rectum

c.     Con be overridden by voluntary contraction of the external anal sphincter

d.     Both A and B above

e.     All of the above

• In the brain the Wernicke's area effects what?

the Broca's area effects what?

• If the storke happened primarily in the left hemisphere then what part of the bodie will be affected?

• Wernicke's- connecting words to object, knowing meanings of the word. -Broca's- forming the words with your mouth
• right side of body

Sleep-wake cycles are controled by activities in the:

• Reticular formation-arousal
• Hypothalamus-slow-wave
• Brainstem- paradoxal

-rapid eye movement

-passes through slow wave stages before entering paradoxil sleep

-deaming or nightmares occur during paradoxil sleep 

a vib- nevous, too much coffee

v vib- going into cardiac arrest

hemoglobin has highest affinity for ____

hemoglobin can bind to ____

carbon monoxide

4 Os or 2 carbon dioxides