Digestive system

• Digestive system


  Responsible for breaking down the food that we eat into small particles that can be absorbed into the bloodstream and transported to the cells throughout our body
• Digestive system processes


  1. Ingestion

  2. Digestion

  3. Absorption

  4. Egestion
• Our cells need protein, carbohydrates, fats, vitamins and minerals to function.
• The food we eat is too big to pass through the selectively permeable cell membranes, so the digestive system breaks it down into small particles that can be absorbed into the bloodstream.
• The seven building blocks of a healthy diet

  • Proteins
  • Carbohydrates
  • Fats and oils
  • Vitamins
  • Minerals
  • Fibre
• Types of digestion


  • Mechanical digestion
  • Chemical digestion
• Mechanical digestion


  Food is physically broken down through chewing, churning and mashing. Occurs in the mouth and stomach.
• Chemical digestion


  Different digestive enzymes break down the bits of food into smaller molecules. Starts in the mouth, also occurs in the stomach and small intestine.
• Enzymes


  Special proteins that speed up certain chemical reactions in the body
• Ingestion

  When you take food into your body through your mouth by eating or drinking
• Digestion


  The process of breaking down large food pieces into particles that are small enough to pass through cell membranes
• Absorption *

  When digested particles move into the cells of the digestive tract (they are absorbed) and move to the bloodstream from where they carried to all the cells in the body
• Egestion


  Any unwanted particles that travel through that digestive tract or passed out as faeces
• alimentary canal


  A Long twisted pipe structure which is 9 m long that starts at the mouth and ends at the anus
• Mouth and oesophagus


  Digestion starts in the mouth as food is chewed and makes with saliva then travels down the oesophagus when you swallow
• Stomach


  The chef enters the stomach and is further digested. The stomach also contracts to break the food down further into a liquid
• Small intestine*


  Most of the digestion and absorption of the food particles
• Large intestine


  By the time the food reaches the large intestine most of the nutrients have been absorbed what’s left is water salts and indigestible fibre the water that is left is then absorbed
• Rectum and anus


  Faeces are passed into the rectum and then I’ll do the anus aka egestion
• Ulcers


  Open source develop on the learning of the mouth oesophagus stomach or the upper part of the small intestine. This is caused by bacterial infections and some medication
• Anorexia nervosa


  And eating disorder people who suffer from this have a fear of gaining weight and starve themselves on purpose.

  Can lead to bone thinning, kidney damage, heart problems or death
• Diarrhoea


  Someone who passes very frequent loose watery stools. Some diseases cause undigested food to pass through the large intestine too quickly for water to be absorbed
• liver cirrhosis


  Slowly replaces healthy liver tissue with scar tissue and prevents lower from functioning properly. Alcohol abuse and fatty liver caused by obesity and diabetes are common causes
• Proteins


  Build and repair body cells and tissues.

  Fish, meat, eggs, cheese, nuts, beans
• Carbohydrates


  Main supply of energy for our bodies.

  Break down in our digestive system to form glucose.

  Whole-grain bread, potatoes, pasta, rice, fruits
• Fats and oils


  Protect and insulate organs.

  Maintain healthy hair and nails.

  Some vitamins can only be transported when attached to fat molecules.

  Provide body with energy.
• Vitamin A


  Strengthens immune system and good for eyesight in the dark
• Vitamin B


  Helps process energy from food and works in the nervous system
• Vitamin C


  Helps keep skin and gums healthy and improves immune system
• Vitamin D


  Builds strong bones and teeth
• Vitamins


  Main source of energy energy from fruits and vegetables
• Iron


  Healthy blood, eg meat
• Magnesium


  Strong bones, teeth and muscles, eg milk
• Sodium


  Muscle and nerve function and regulates the amount of water in blood, eg salt
• Calcium


  Strong bones and teeth, eg dairy products
• Fibre


  Can’t be digested and travels through alimentary Canal. Help avoid constipation, found in the skin of fruits and vegetables
• Water


  Bodies are made up of more than 50% water.

  Helps blood carrying nutrients and waste around body and helps chemical reactions take place
• Starch test is a test for starch in the food
• Emulsion test is test for the presence of fats and oils in food
• Osteoporosis


  Bones become fragile and likely to break and lose density.

  Lack of calcium.