Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.
Digestion Summary:Food digested as passes along ________________________.-> consists of the mouth, pharynx, esophagus, sto...
Exocrine glands and their cells:Digestive juice secretion:- controlled by ___________ and _______________- before food rea...
Membrane-bound digestive enzymes:- some enzymes, produced by the wall of the small intestine, don’t mix with the food but ...
Upcoming SlideShare
Loading in …5
×

Further human physiology: digestion

821 views

Published on

This handout

Published in: Education
  • Be the first to comment

Further human physiology: digestion

  1. 1. Digestion Summary:Food digested as passes along ________________________.-> consists of the mouth, pharynx, esophagus, stomach, small intestine, and largeintestine.___________________and _____________ muscle fibers in its wall contract and relax,squeezing food and breaking up large solid lumps. Digestive juices (secreted by________________________, _______________________________and ____________=_______________________) with enzymes mix with food to break down the molecules(proteins, nucleic acids, starch etc.) into smaller soluble forms.Indigestible macromolecules: e.g. _____________(part of dietary fiber). Humans lack________________(enzyme which digests cellulose). Cellulose moves food through thedigestive tract quickly and efficiently, though.Exocrine glands- secrete their products into ducts which lead directly to external environment- digestive juice released from cells by exocytosis => discharged from gland by traveling along ducts
  2. 2. Exocrine glands and their cells:Digestive juice secretion:- controlled by ___________ and _______________- before food reaches stomach, sight or smell of food stimulate brain to send nerve impulses to _____________________in stomach wall to produce _________________.- More gastric juice secreted when food enters stomach and comes into contact with__________________________ and ______________________ in the stomach liningand ________________________in the stomach wall. - Receptors send nerve impulses to brain -> sends impulses to ____________ gland cells - Receptors send nerve impulses to ___________ gland cells in stomach lining -> secrete hormone: ___________ -> carried to exocrine gland cells to stimulate_______________________________ => causes ph of food in stomach to fall to aboutpH 3.0
  3. 3. Membrane-bound digestive enzymes:- some enzymes, produced by the wall of the small intestine, don’t mix with the food but remain in the ________________________ of cells on the surface of the villi (epithelium cells)- the ___________________ of the enzymes are exposed to the food in the small intestine-> digest substrates and the products of digestion can be immediately absorbed.- After abrasion of tips of villi, the enzymes mix with food in small intestine and continue workSources of digestive enzymes:- pepsin & trypsin harmful to exocrine gland cells which secrete them.-> secreted as ______________________________ (a substance from which anothersubstance is formed) called pepsinogen and trypsinogen.Pepsinogen: first secreted by cells in ____________________ and then activated by_______________________(also secreted by cells in stomach wall), which converts itinto pepsinTrypsinogen: first secreted by _____________ and enters ________________________.Then activated by enzyme called __________________ (secreted by lining of smallintestine)

×