Flashcards in Digestive system Deck (19)
function of the digestive system
to break down food into tiny particles,
to pass nutrients into the blood to be used by the body,
to excrete waste matter
two types of changes in digestion
teeth cut and grind food into smaller particles in the mouth,
the stomach churns the food into a smooth mixture called chyme.
chemical change - what is an enzyme?
Enzymes are chemicals present in digestive juices that help break food down into smaller particles for absorption into the blood. Each enzyme works on one nutrient.
chemical changes (eg protein)
Proteins are changed into amino acids,
Fats are changed into fatty acids and glycerol
carbohydrates are changed into simple sugars, eg glucose and maltose.
parts of the digestive system
mouth, oesophagus, stomach, small intestine, large intestine, pancreas, liver.
function of the mouth
The mouth cut and grind the food into smaller particles. The food also mixes with saliva. Saliva contains an enzyme called salivary amylase, which changes carbohydrates (starch) into maltose.
Function of oesophagus
the oesophagus joins the mouth to the stomach. It pushes the food to the stomach.
What is peristalsis?
Peristalsis is a muscular movement that pushes food along in the oesophagus and the large intestine.
function of the stomach
The stomach stores the food and churns it into a smooth liquid called chyme. The chyme gradually goes out of the stomach into the small intestine.
what is pepsin (in stomach)
An enzyme called pepsin is made in the stomach. Pepsin changes protein into peptide chains. Acid is produced in the stomach to help pepsin to work.j
function of small intestine
Bile, pancreatic juice and intestinal juice are added to food in the small intestine.. Digested food is absorbed in the small intestine.
the pancreas produces enzymes.
the gall bladder in the liver produces bile, which helps to break down fats.
what are villi?
Villi are tiny hair-like fingers that cover the inner layer of the small intestine. Digested food goes from the small intestine into the blood through the villi.
order of nutrients going into the blood through villi
glucose and amino acids go directly into the blood.
Fatty acids and glycerol go into the lymph system first and then into the blood.
The blood transports the digested food around the body, where it is used in the cells for growth and energy.
nutrients made in the large intestine
vitamin K and B
fibre in the diet
Fibre in the diet makes the wastes bulky, which helps the movement of waste along the intestine.