Digestion Flashcards
Process whereby muscles in oesophagus contract/relax to squeeze food from mouth to stomach
Peristalsis
Definition of Digestion
The breakdown of insoluble molecules into soluble molecules for absorption into bloodstream
Digestion of proteins
Protease enzymes breakdown proteins into amino acids to make new proteins in body
Digestion of fats
Lipase enzymes breakdown lipids into glycerol and fatty acids which are then used in respiration to provide energy
Digestion of carbohydrates
Carbohydrase enzymes break down carbohydrates into simple sugars for energy used in respiration
E.g. Amylase digests starch into glucose
Bile, where is it produced, stored and what does it do?
- Produced in liver
- Stored in gallbladder
- Emulsifies fats, increases surface area for Lipase to break down lipids (quicker digestion)
Describe what happens to fat once it has passed out of the stomach (QWC)
- Fat enters small intestine
- Bile enters small intestine from gallbladder where it’s stored
- Bile emulsifies fat molecule so large fat droplets are broken down into smaller fat droplets
- Lipase enzyme produced by small intestine and pancreas can digest fat quicker due to large surface area
- Fat digested into fatty acids and glycerol by lipase, these small soluble molecules then pass into bloodstream by absorption
Sugar test
- Crush small amount of food with distilled water in pestle and mortar
- Add 5ml of this to test tube
- Add 10 drops of Benedict’s solution
- Heat in water bath at 80 Degrees Celsius for 2-3mins
- Solution turns from blue to green/yellow/red depending on concentration
Starch test
- Crush small amount of food with distilled water in pestle and mortar
- Add 5ml of this to test tube
- Add 5 drops of iodine solution and gently shake
- Turn from orange/brown to blue/black
Protein test
- Crush small amount of food with distilled water in pestle and mortar
- Add 5ml of this to test tube
- Add 10 drops of Biuret solution and gently shake
- Turn from blue to violet/pink colour
Fat test
- Rub small amount of food onto brown paper
- Paper will go translucent
