1 pharynx
Download
1 / 61

1. Pharynx - PowerPoint PPT Presentation


  • 228 Views
  • Uploaded on

1. Pharynx. cavity not involved in digesting food passageway leads to stomach connection between nasal & oral cavities to larynx & esophagus. 3 parts to pharynx. nasopharynx - connects w/ nasal cavity oropharynx - passageway food moving down & air moving into trachea

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about ' 1. Pharynx' - kitty


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
1 pharynx
1. Pharynx

  • cavity

  • not involved in digesting food

  • passageway leads to stomach

  • connection between nasal & oral cavities to larynx & esophagus


3 parts to pharynx
3 parts to pharynx

  • nasopharynx- connects w/ nasal cavity

  • oropharynx- passageway food moving down & air moving into trachea

  • laryngopharynx- passageway to esophagus


3 stages of swallowing
3 Stages of Swallowing

  • 1st stage:

    • voluntary

    • food chewed- mixed w/ saliva

    • rolled into mass by tongue- BOLUS- forced into pharynx


2 nd stage swallowing reflex stimulated
2nd Stage- swallowing reflex stimulated

  • food is prevented entrance to nasal cavity

  • epiglottis slaps shut over larynx to keep food from going down trachea

  • tongue seals off oral cavity

  • different muscle actions open esophagus & forces food down it


epiglottis

trachea


3 rd stage
3rd Stage

  • breathing momentarily inhibited

  • peristalsis transports food down into & through esophagus

  • choking occurs when food lodges in larynx

  • Heimleich maneuver can dislodge food


Heimleich maneuver
Heimleich maneuver


2 esophagus
2. Esophagus

  • straight tube

  • ~ 25 cm long

  • food passageway from pharynx to stomach

  • goes thru opening in diaphragm

  • contains mucous glands w/ secretions that moisten & lubricate inner lining


Peristalsis
Peristalsis

  • wavelike motion propels food down tubular structures

  • contraction of muscle occur above food & relaxation below it


  • hiatal hernia

  • acid reflux

  • Barrett’s esophagus



3 stomach
3. Stomach

  • j-shaped, pouched organ

  • ~ 1 L capacity

  • fxns: receives food from esophagus, mixes food w/ gastric juices, begins protein digestion, limited absorption, moves food into small intestines


Regions of stomach
Regions of stomach:

  • cardiac-

  • fundus- temp storage area

  • body- main part

  • pylorus- approaches small intestines


  • inner lining contains gastric glands w/ 3 types secretory cells:

    • mucous cells- secrete mucus w/ other secretions keeping stomach from digesting itself

    • chief cells- secrete digestive enzymes- pepsinogen

    • parietal cells- release HCl & intrinsic factors

      all these form GASTRIC JUICE (2-3 L/day)



inner lining= RUGAE- disappears when stomach is distended

ulcer is open sore in the lining of stomach

may be caused by presence of H pylori bacteria


  • pepsinogen is released & when hits HCl forms PEPSIN which digests almost ALL types of protein

  • intrinsic factors aid in vitamin B12 absorption in small intestines

  • mostly digestion occurs in stomach, but some absorption of water, salts, and drugs does occur


mechanical & chemical digestion begin here

resulting in a semi-paste called CHYME

rate at which this enters sm intestine depends of type of food

liquids pass thru quickly

fatty foods 3-6 hours

proteins & carbs pass thru more quickly


Vomiting
Vomiting

  • medulla oblongata- vomiting center

  • body prepares for the process by closing off nasal cavity, trachea, contraction of diaphragm, contraction of abdominal muscles, etc


4 pancreas
4. Pancreas

  • dual fxn- endocrine gland & digestive gland

  • closely associated w/ small intestine in the curve of duodenum

  • fxn: release pancreatic juice

  • juice contains enzymes that digest carbs, fats, nucleic acids, proteins



5 liver gallbladder
5. Liver & Gallbladder of juice

  • largest internal organ in body

  • inferior to diaphragm on right side of body (under ribs)

  • 4 lobed organ (2)

  • connected to sm intestines by ducts

  • main fxn: manufacture bile salts


Functions
Functions: of juice

  • imp role in carb metabolism

    • regulates glucose in bld

  • imp in lipid metabolism- converting subst into fats (bile salts)

  • imp in protein metabolism




Diseases of liver
Diseases of Liver body

  • cirrhosis

  • hepatitis

  • cancer


  • surrounds bodygallbladder- small, green sac embedded in liver

  • stores & concentrates bile



6 small intestine
6. Small Intestine body

  • major digestive organ

  • ~ 21 feet long

  • 3 subdivisions:

    • duodenum- ~10” long (25cm)

      diameter: ~ 2” (5cm)

      C-shaped around the pancreas

      B. jejunum- ~ 8’ long

      greater diameter

      thicker walls, more vascularized


C. ileum- ~ 12’ long body

hard to distinguish between jejunum & ileum


  • mesentery body- thin membrane that suspends the portions of the intestines from walls

  • contains blood vessels, nerves, lymphatic vessels




  • carries on mixing movements & peristalsis body

  • chyme moves slowly; 3-10 hours

  • if wall becomes distended/irritated, a peristaltic rush pushes contents to large intestine so quickly that water, nutrients, & electrolytes aren’t absorbed - diarrhea


8 large intestine
8. Large Intestine body

  • ~ 5’ length

  • greater diameter than small int

  • fxns:

    1. dry out indigestible food residue by absorbing water

    2. eliminate residues from body as feces


  • little or no digestive bodyfxns

  • no secretions except mucus by goblet cells in wall

    • protects inner wall

    • binds fecal matter

  • normally absorbs water & electrolytes

  • many bacteria, intestinal flora, inhabit organ (100 trillion)

  • help break down substances that aren’t by our digestive system


  • 4 principle regions: body

    • cecum- beginning; dilated pouchlike

      contains appendix (appendicitis)

    • colon- subdivided into 4 parts:

      a. ascending colon- right side

      b. transverse colon- across

      c. descending colon- left side

      d. sigmoid colon- s-shaped

      3. rectum

      4. anal canal



Major prob colon cancer
major bodyprob: colon cancer


ad