Enzymes, Food Tests And Digestion Flashcards
What are enzymes ?
- Enzymes are catalysts in chemical reactions (E.g digestion of food)
Give an example of when the use of enzymes are key.
- Digestion of food
- The control of one’s metabolism
Key structural parts of an enzyme.
- Active sites (which have a unique shape)
- Each enzyme has a unique active site. The substance involved in the chemical reaction will have to fit into the active site for the enzyme to work
- Enzymes are really specific so will usually catalyse (speed up) one specific reaction
What two things are key for an enzyme to be successful?
- Ph level
- Temperature
What does temperature effect ?
- Temperature effects the Rate of reaction
- An increased temperature increases the rate of reaction
- A decreased temperature decreases the reaction rate
What happens if the temperature is too high ?
- The enzyme DENATURES
- Binds will start ti breach which holds the enzyme together which will make the enzyme less effective
What is different between all enzymes ?
- All enzymes have different optimum temperatures (The best/most efficient template which the enzyme works at)
What does Ph effect in an enzyme ?
- Ph also effects the rate of reaction of an enzyme
Why do you need to consider the Ph while using enzymes ?
- If the Ph is too high or low it affects the bonds in which hold the enzyme together. If the bonds become denatured the active site shape changes which leads to the enzyme not being able to be used.
What does the enzyme of amylase promote ?
- The breakdown of strath to sugar
How can you detect if starch is present ?
- The use of iodine solution
- If starch is present the iodine solution will change from browny-orange to a blue-black colour
How do you calculate rate of reaction ?
Rate of reaction = 1000/Time(S)
What is the Benedict’s test used for ?
- To test for the presence of reducing sugars (e.g Glucose)
- If sugars is detected the solution will change colour from blue to either green, yellow or brick-red. (This depends on how much sugar is in the food)
What is the Iodine test used for ?
- To test for the presence of starch
- if starch is present the solution will change colour from browny orange to either black or blue-black
What is the test for Lipids ?
- Sudan III (3)
- If the food contains lipids the mixture will separate into two layers.
- The top layer will be bright red
Why do we need digestive enzymes ?
- To break down larger molecules such as starch, protons and fats to be able to pass through the walls of the digestive system.
- So digestive enzymes breaks down larger molecules into smaller ones
What are the benefits of having smaller molecules over larger molecules ?
- So the food can pass through the digestive system easily
- So the smaller, soluble molecules can be absorbed into the bloodstream.
What is starch (a charbohydrate) broken down by ?
- Amylase
- Amylase is a carbohydrase
- Amylase is mad in the salivary glands pancreas and small intestine.
- Amylase works in the mouth and small intestine to break down food
What is starch broken down into ?
- Sugars
- (E.g Glucose)
What are proteins broken down by ?
- Protease
- Proteases are made in the stomach, pancreas and small intestine
- They work in the stomach and small intestine
What are protons broken down into ?
- Amino acids
What are broken down into Glycerol and fatty acids ?
- Lipids
What is lipases used for ?
- The break down of lipids
- Lipases are found in the pancreas and small intestine
- They work in the small intestine
What is the use of Bile ?
- Neutralises the stomach acid
- Emulsifies fats
Is bile acidic or alkaline ?
- Alkaline
Where is bile produced and stored ?
- Produced in the liver
- Stored in the gall blader
Where is bile released into ?
- The small intestine
Where is bile released into ?
- The small intestine
What is the process of emulsification of fats ?
- The break down of fats into smaller droplets.
- This gives a bigger surface area of fat for lipase to work on.
- This makes digestion a faster process
Why is bile released into the small intestine ?
- Because the enzymes in the small intestine work best in alkaline conditions
