The stomach Flashcards
what shape is the stomach
large muscular, J shaped sac
what does the stomach act as
a reservoir
how long does a heavy meal stay in the stomach for
after a heavy meal, food stays 3-4hr in the stomach
how much can the stomach hold
the stomach can stretch to hold 2L of food
how does the stomach mechanically digest food?
Mechanical digestion in the stomach is achieved by waves of muscular contraction that move along the stomach wall. The stomach’s oblique, circular and longitudinal muscles enable the stomach to contract in a variety of ways to churn food and mix it with stomach juices. The stomach breaks down food into a soup-like consistency called chyme
what is the structure of the stomach/different muscles
- oblique muscle
- longitudinal muscle
- circular muscle
where is the oblique muscle found
only in the stomach
how does the stomach chemically digest food?
Chemical digestion occurs through the pepsin enzyme which is secreted in an inactive form called pepsinogen which is activated by HCl. The pepsinogen is inactive to prevent the digestion of the stomach.
This breaks bonds between amino acids so the chains that form protein are broken down into polypeptides.
what does HCl do to food
it kills the bacteria
instead of HCl which infants have
rennin in stomachs of infants
how long does food stay in the stomach for
2-8hr
- carbohydrates and proteins don’t stay long, but fats stay the longest
