Class notes
Lecture GI tract
- Course
- Institution
Lecture BBS1002 GI tract December 2018.
[Show more]
Seller
Follow
cc103169
Content preview
Lecture the gastrointestnal system Overview of functon GI tract :
o Chew the food,
o Lubricate saliva
o Transported
o Stomach acid mixes with food.
o Digeston and reabsorpton in
intestnes.
Fluid in the small intestne:
o 2 L food
o 1,5 L saliva
o 2 L gastric juice
o 2 L pancreatc juice /bile
o 1 L small intestnal secreton
Big load of small intestne from -10 litres
o Reabsorbed: 6.5 L
o Presented to colon: 2 L
o Reabsorbed: 1.9 L
o Colon excreton feces) +/- 200 g
On average you consume 2 litres of food, includes fuids.
Structure of the lecture:
o Digestve secretons
o GI motlity
o Neural and hormonal regulaton
Digestve secretons
o Starts in the mouth saliva lubricaton in
mouth, otherwise our mouth is very dry and it is
difcult to mix with the food.
o Lubricaton is do due the mucins in saliva: these
are glycoproteins.
o The digeston starts because there is some
amylase produced and a litle bit of lipase. litle bit of fat digeston.
o We do also have a lot of antmicrobial proteins in our saliva, this is to protect
us against for example bacteria. also the water content helps with
protecton)
o Ph is litle bit basic to protect us against acid food.
Parotd serous amylase and lipase)
Sublingual mainly mucous, bit serous glycoproteins)
, Submandibular serous/ mucous
Ions, water, mucins, a amylase, lipase, antmicrobial proteins.
Lubricaton, dissolving, start
digeston, protecton.
o Secretory unit of saltatory gland
o The head of the gland is visible `9 the upper part
with the bigger cells, and the acinus.
o The head is responsible for the primary secreton:
Ions, mucous proteins, enzymes and the
antmicrobial proteins
o Then we have the duct cells:
Rate of secreton is slow, tme for
reabsorpton in the duct cells.
Sodium and chloride
o Sodium is absorbed in
exchange for potassium.
o Chloride is absorbed in
exchange for Bicarbonate.
Slow secreton rate: hypotonic
High secreton rate: hypertonic actve secretng of. Bicarbonate.
Less acid.
o Secreton in the stomach:
Stomach depicted: Stomach upperpart; fundus part.
The big corpus: The body, we also call it the oxyntc mucosa.
Oxyntc: the acid secreton part
The antrum part.
Diferent regions in the stomach: the region where the acid is secreted
and the region with the more regulatory functons.
Folds in the layer and glands.
A lot of cell types in glands:
o Superfcial epithelial cell bicarbonate, mucous
Bicarbonate to countract the acid
, Very watery mucous secreton.
o Mucous neck cells/ goblet cells mucous
protecton
o Parietal cells/oxyntc HCl, intrinsic factor,
gastroferrin
Intrinsic factor is needed for the absorpton of
vitamin B12, this is needed for maturaton of red
blood cells.
o Chief cells pepsinogen and lipase
Actvated to pepsin
o Endocrine cells gastrin, histamine, somatostatn
Peptde hormones for regulaton
Functon of gastric acids
o Protecton of gastric mucosa.
o Acid: ph below 2
Actvates pepsinogen
Denaturaton proteins
Protecton against bacteria
o Mucosa needs to be protected against the acid. Alkaline mucus layer
Mucous secreted by neck cells.
Chemical and mechanical protector.
o Inhibits prostaglandin synthesis paracetamol /
ibuprofen.
Prostaglandin: stmulated the mucous secreton
and acid secreton.
small intestne:
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through EFT, credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying this summary from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller cc103169. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy this summary for R59,23. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
67232 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy summaries for 14 years now