food and nutrition ks3

• food passes through the digestive system by peristalsis which is when muscles contract to push food along
• teeth are used to break down food into smaller pieces so it can be swallowed more easily
• tongue helps move food around your mouth and mixes with saliva
• saliva contains enzymes to break down carbohydrates into sugars
• enzymes are chemicals that speed up chemical reactions
• food passes through the digestive system by peristalsis which are waves of muscle contractions that move food along
• the digestive system is made up of the mouth, oesophagus, stomach, small intestine, large intestine, rectum and anus
• when we swallow, food goes from the mouth to the pharynx (throat) then down the oesophagus (gullet)
• What are nutrients? Substances that are required in small amounts by the body for growth and repair
• What is malnutrition?


  Deficiency in nutrients. Caused by lack of proper nutrition, not having enough to eat, not eating enough of the right things, or being unable to use the food that one does eat.
• What is an example of a balanced diet?

  A balanced diet includes a variety of fruits, vegetables, whole grains, lean proteins, and healthy fats.
• What is a food test?

  A food test is a scientific experiment or analysis conducted to determine the presence or absence of specific nutrients, contaminants, or other substances in a food sample.
• How can we test for sugars/starch/fats/proteins/etc in a food test?


  Sugars: Benedict's test

  Starch: Iodine test

  Fats: Sudan III test

  Proteins: Biuret test
• What is a food label and why are companies forced to use them?

  A food label is a printed information panel on food packaging that provides details about the product's ingredients, nutritional content, and other relevant information. Companies are required to use food labels to ensure transparency, inform consumers about the product's contents, and comply with food safety regulations.
• What is the function of the mouth in the digestive system?

  The mouth is responsible for the initial mechanical and chemical digestion of food through chewing and the release of saliva.
• What is the function of the oesophagus in the digestive system?

  The esophagus is a muscular tube that connects the pharynx (throat) to the stomach. The esophagus contracts as it moves food into the stomach
• What is a reagent?

  A substance used in a chemical reaction to detect, measure, or produce other substances.
• What does the stomach do in the digestive system?

  An organ with strong muscular walls, the stomach holds the food and mixes it with acid and enzymes that continue to break the food down into a liquid or paste.
• What does the pancreas do in the digestive system?

  Produces insulin and digestive enzymes.
• What does the small intestine do in the digestive system?

  The small intestine absorbs most of the nutrients in your food, and your circulatory system passes them on to other parts of your body to store or use. 
• What does the small intestine do in the digestive system?

  At the end of the large intestine is the rectum, a reservoir that holds stool until it can be passed out of the body.
• Can you name the organs in the digestive system in order from start to finish?

  Mouth, oesophagus, stomach, small intestine, large intestine, rectum, anus.
• What is the function of the rectum in the digestive system?

  The function of the rectum in the digestive system is to store feces before they are eliminated from the body through the anus.
• What is the function of the anus in the digestive system?

  The anus is the opening at the end of the digestive tract where solid waste is eliminated from the body.
• What is the function of the liver in the digestive system?

  The liver produces bile, which helps break down fats, and detoxifies harmful substances in the body.
• What are the seven steps of digestion in order?

  The digestive processes are ingestion, propulsion, mechanical digestion, chemical digestion, absorption, and defecation. However, some chemical digestion occurs in the mouth.
• What is the result of the iodine solution to find starch if successful?

  Turns blue with starch
• What is the result of Benedict's Solution to find reducing sugars when carried out successfully?

  Turns red (brick) with reducing sugars (green/yellow/orange if sugar less present)
• What is the result of Biuret's Solution to find protein if successful?


  Turns purple with protein
• What is the result of putting ethanol onto food to test for lipids?

  The ethanol will evaporate leaving a greasy, milky residue
• Can you define an organ?

  A group of tissues that work together to perform a specific function in the body.
• Can you define enzymes?

  An enzyme is a biological catalyst and is almost always a protein. It speeds up the rate of a specific chemical reaction in the cell. The enzyme is not destroyed during the reaction and is used over and over.
• How do enzymes speed up digestion?

  Enzymes speed up digestion by breaking down large molecules into smaller ones
• What are enzymes sensitive to?

  Temperature, pH, and substrate concentration.
• Proteins, which are made up of a chain of amino acids are called polypeptides, and are the building blocks of proteins, are broken down by?


  Protease Enzymes
• Starch, which is made up of glucose molecules, are broken down by what?


  Amylase Enzymes
• What is fat broken down by?


  Lipase Enzymes
• Fats, for e.g. pastries, nuts, avocados and soya beans, are important for our body because?


  They help carry vitamins around our body, they help keep us warm, and they help protect our organs
• Carbohydrates, for e.g. corn, watermelons, pasta, bread and rice, are important for our bodies because?


  They provide energy to the body
• Protein, for e.g. chicken, tofu, fish, seeds and meat, are important for our bodies because?


  They help to repair muscles and help us to grow