1 / 26

8A Food and digestion

8A Food and digestion. 8A Food and digestion. Food. Balancing your diet. Digestion. 8A Food and digestion. Food. 8A Food – who needs it?. Energy to do things. Raw materials to grow larger. Raw materials to repair damaged body parts. What do we need food for?. 8A So what’s in food?.

lin
Télécharger la présentation

8A Food and digestion

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. 8A Food and digestion 8AFood and digestion Food Balancing your diet Digestion

  2. 8A Food and digestion Food

  3. 8A Food – who needs it? Energy to do things Raw materials to grow larger Raw materials to repair damaged body parts What do we need food for?

  4. 8A So what’s in food? Proteins Fats Carbohydrates (starch and sugars) Roughage Vitamins Minerals Water Food is a complicated mixture of different chemicals. We can sort these chemicals into different types. What are the main types? Can you make up a sentence with words starting with the same letters – a mnemonic?

  5. 8A Which food contains which chemical? Which foods belong to which food groups? Proteins Water Fats Carbohydrates Proteins Fats Carbohydrates Water

  6. 8A What’s in food? Orangey-brown iodine turns blue-black when it reacts with starch. We can test foods to find out what chemicals they contain. drop iodine solution onto the food black = starch

  7. 8A What’s in food? Blue Benedict’s solution turns orangey-red when it is boiled with glucose. blue turns orange/red= glucose chopped up food hot water heat

  8. 8A What’s in food? In the Biuret test the solution turns purple. potassium hydroxide coppersulphate shake purple = protein chopped up food

  9. 8A What’s in food? Fats go cloudy white when they are mixed with ethanol and water. add water filter grind food with ethanol cloudy = fat Now see if you can use these tests to identify the food chemicals on the next slides.

  10. 8A What’s in food? For each food, decide on the chemicals found in them. Protein Fats Starch Glucose

  11. 8A What’s in food? For each food, decide on the chemicals found in them. Protein Fats Starch Glucose

  12. 8A What’s in food? For each food, decide on the chemicals found in them. Protein Fats Starch Glucose

  13. 8A What’s in food? For each food, decide on the chemicals found in them. Protein Fats Starch Glucose

  14. 8A Vitamins Liver, butter, green vegetables Healthy skin and teeth A Healthy skin Cheese, milk, liver, eggs, green vegetables B2 Citrus fruits, green vegetables, potatoes Healthy teeth and gums, without it you get scurvy C Fish liver oil, eggs, sunlight on the skin Healthy bones – without it you get rickets (soft bones) D

  15. 8A Food and digestion Balancing your diet

  16. 8A A food test for YOU! 1.A balanced diet… a)contains the same amounts of the main food groups b) contains healthy amounts of the main food groups c)doesn’t fall off the table. 2.A balanced diet for most people has more… a)fat than water b) carbohydrate than protein c)crisps than fruit.

  17. 8A A food test for YOU! 3.To test for protein in food you… a)add iodine solution b) do the Biuret test c)poke it with a big stick. 4.Sugar and starch are both… a)proteins b) fats c)carbohydrates.

  18. 8A A food test for YOU! 5.Iodine solutions turns blue-black with… a)starch b) protein c)age. 6.A food went orangey-red when it was boiled with Benedicts solution. It could be… a)a carrot b) a boiled sweet c)a sausage.

  19. 8A A food test for YOU! 7.Not enough vitamin C gives you… a)headaches b) scurvy c)weak bones. 8.Riboflavin is… a)a B vitamin b) a fruit drink c)an elf from The Lord of the Rings.

  20. 8A Food and digestion Digestion

  21. 8A Why digestion? Food is a mixture of molecules. Some of these molecules are too large to pass into the body. Digestion breaks down food in the gut into smaller molecules. The body uses these smaller molecules for energy or to build body parts.

  22. 8A Where it all happens What happens where? Follow the food down through the body. Mouth breaks large lumps of food into smaller lumps. Stomach produces enzymes to break down proteins. Intestines produce enzymes to break down proteins, carbohydrates and fats. Start to absorb food into body. Colon absorbs water and stores waste until time to pass out of the body.

  23. 8A Watching the digestives

  24. 8A Absorbing stuff

  25. 8A Digestion - True or False? True or False? 1.Enzymes are made of protein. 2.Enzymes only work in acid solutions. 3.Enzymes can only break down molecules. 4.A protease is an enzyme that breaks down protein into smaller molecules. TRUE FALSE FALSE TRUE

  26. 8A Digestion - True or False? True or False? 1.An enzyme works best at a particular temperature. 2.Most enzymes in the human body work best at about 57°C. 3.Enzymes work best in boiling water. 4.Snakes produce one enzyme that can digest everything in its victim from the skin to the bones. 5.Amylase is an enzyme that breaks down starch. TRUE FALSE FALSE FALSE TRUE

More Related