The digestive system
Food is broken down into substances that our bodies can use. This is called Digestion& with out digestion we caouldn't absorb food into our bodies & use it.
Digestion happens in the Digestive system which begins at the mouth& ends at the ****.
Food passes through these organs:
Stages of digestion:
Food is digested in the mouth, stomach& small intestine.
Digested food is absorbed into bloodstream in the small intestine.
Excess water is absorbed back into the body in large intestine.
Undigested food passes out of the **** as faeces.
Liver produces bile which helps digestion of fat. The pancreas produces pancreatic juice aslo know as digestive enzymes.
Passage of food in the gut/ stages of the digestiv
Ingestion- food enters the mouth/beginning of digestive system
Digestion- Food is broken down into smaller molecules
Absorption- Food is absorped into the blood
Egestion- Waste products are excreted.
Mouth- Grind/chew food. Amylase in saliva.
Oesophagus- Food pushed through the Gullet into the stomach.
Stomach- Food is churned&mixed with acid&enzymes. Enzyme Pepsin digests proteins. Works best at pH2.
Small intestine: Pancreatic juice is added. Contains Amylase-Starch digestion
Lipase-fats digestion, Trypsin- Protein digestion.
Pancreatice juice is Alkaline. Bile from liver is added, helps break down fats. Bile&pancreatic juice are BOTH Alkaline.
Food is absorbed into blood.
Bile neutralises acid in the stomach.
Food particles Diffuse into the blood& are carried around the body
Large intestine- water is absorbed.
Rectum- Solid waste/faeces are stored in this part of large intestine/rectum before passing out of the body via the ****.
Villi- tiny finger like projections in small intestine. They increase the surface area of small intestine. Helps absorption of food through the walls of the intestine to the blood.