Further Digestion Flashcards
What type of muscles does peristalisis involve
Longitudinal muscles down the length of the gut
Circular muscles in circles around the gut
What is the gut also known as
The alimentary canal
what job do the muscles do in peristalisis
They squeeze the food along
How are the muscles adapted to their job in peristalisis
Circular muscles- push food along gut
Longitudinal muscles- run ahead to keep food in bolus shape
What are the 2 jobs of bile
Bile neutralises stomach acid as the pH is too acidic for enzymes in the small intestine to work so the alkaline bile neutralises the acidity
It emulsifies fats into tiny droplets that give it the fat a larger surface area for lipase to work on
Where are villi located
Millions line the inside of the small intestine
How do villi improve absorption of digested food into the bloodstream
Large surface area to absorb digested food quicker
Single layer of surface cells so divested food diffuses quickly
Good blood supply via capillary network to help absorption.
Define villi
Finger like folds lining the small intestine
How does coeliac disease affect the villi
It flattens and damages the villi so the surface area decreases and the products of digestion cannot be absorbed properly = person becomes thin
How do the villi allow nutrients to pass into the blood
Through diffusion. The particles move from the small intestine trough the villi wall into the bloodstream by diffusion. The constant blood flow means the concentration gradient stays stable
