Digestive System Flashcards
What organs are in the digestive system and in what order?
Mouth, oesophagus, Stomach, Liver, Pancreas, Small intestine, Large intestine, appendix, anus.
What four types of teeth are there in the mouth and the purpose?
Incisors – Four pairs of teeth at the front. Bites off pieces small enough to chew.
Molars and Premolars – Grind the food into smaller pieces.
Canines – used to hold the food when torn apart.
What is saliva
Contains chemicals that change any starch (complex sugar) in the food into glucose ( a simple and easily absorbed sugar. Saliva also moistens the food making it slippery, slimy and easy to swallow.
What is the oesophagus?
Muscular tube the connects to the mouth at one end and the stomach at its other end. The oesophagus pushes the bolus (tiny ball of food) down the tube by contracting behind the ball. This process is called peristalsis.
What is the epiglottis?
A flap of skin that closes the end of the entrance into the windpipe when you swallow to make sure food doesn’t travel into the lungs.
What is a sphincter?
Separates the oesophagus from the stomach. It is a flap that opens allowing food from oesophagus into the stomach. Then closes to make sure it doesn’t come back up the oesophagus. There is a sphincter at each end of the stomach.
What is the stomach? What does it do? What gastric juices does it contain?
Red and shaped like a bag. Food is stored in their for 1-6 hours. The muscular walls of the stomach begin to contract and relax, mixing up the food. This also mixes the food with gastric juice.
Gastric juice contains:
Hydrochloric acid – A strong acid that kills bacteria
Mucus – Creates a layer on the lining of the stomach and prevents it from digesting itself.
Digestive juices – Contains chemicals that start the digestion of protein, the main nutrient found in meat.
What is the small intestine? What are the parts of the small intestine?
Small intestine – Very long narrow tube up to 6 meters long and a diameter of 3cm.
Duodenum – Is the fist part of the small intestine. Two tubes entering the duodenum carry chemicals important for digestion. These tubes come from the pancreas and the liver. The walls are very muscular. It continues to squeze and churn the food and makes sure that the digestive chemicals are fully mixed, while it passes down into the small intestine.
Pancreas – Not a part of the digestive tract. Organ connected to small intestine which produces pancreatic juice. This juice contains chemicals that help digest carbohydrates (startches and sugars) fats, and protein.
Ileum – Lower part of intestine. When food is in the ileum, it is in the form or very tiny particles that can be absorbed. The food is digested into ileum. On the inner lining of the ileum are villi (singular villus).
Villi – Microscopic fingers that greatly increase the surface are of the intestine wall and through which the nutrients pass, to absorb more. Within the Villi are tiny blood vessels called capillaries.
Nutrients that pass from the small intestine are:
Fatty acids and glycerol, produced from the digestion of fats.
Amino acids, produced from digestion of protein.
Glucose, produced from digestion of carbohydrates.
What is the liver?
Largest internal organ and performs over 500 different processes. The process in the liver that is important for digestion of bile. Bile is a greenish liquid that is resoinsible for the mechanical digestion of fats. Bile causes large pieces of fat I food to be broken down into tiny pieces so that they can be digested more easily.
What is the large intestine?
The large intestine is the final section of your digestive tract and is 4.5 meters long and has a diameter from 6-7cm. In the large intestine water is reabsorbed from what is left of the food, along with remains of nutrients. The waste forms limps of faeces (known as stools and poop). These are later expelled from the body through the anus. The anus is a sphincter muscle at the end of the digestive tract. Faces are 60% water, one third bacteria, another mineral salts and gut lining and undigested food.
