digestive system Flashcards
Define the digestive system.
The digestive system is a group of organs that work together to convert food into energy and nutrients to feed the body.
What are enzymes?
Substances which can increase the rate of chemical reactions without being used up.
How do enzymes help with the digestive system?
Enzymes helps with breaking down the food so they are converted into small soluble chemicals that the body can absorb into the blood.
What are the 3 types of enzymes in the digestive system?
AMYLASE - Breaks down carbohydrates - Found in the saliva, and digests the longer, complex molecules into simpler molecules.
PROTEASE - Breaks down proteins - Found in stomach and pancreas, and cuts up the amino acids to be absorbed in the small intestine.
LIPASE - Breaks down fats - Found in pancreas and the walls of small intestine and cuts the fat up to be absorbed.
How does the digestive system work?
- Ingestion - Chemical digestion starts when food is ingested through mouth, and the amylase enzymes start to break starch down and the teeth breaks the food down.
- Stomach - the food Is moved to the stomach and the chemical digestion continues with the help of hydrochloric acid and enzymes in gastric juices. The food is broken down by the stomach.
- Small Intestine - Lipase is produced in small intestine wall and the pancreas to continue chemical digestion. Small intestine is lined with villi to help the food be absorbed from gut to blood by having a bigger surface area to maximise absorption.
- Large Intestine - The indigestible food is moved to the large intestine for excess water, salt and soluble vitamins to be absorbed before excretion.
What is Peristalsis?
Is the automatic wave-like movement of the muscles that line the GI Tract. It helps food move through the digestive system by contractions of 2 sets of muscles in the gut.
