B3 organisation and digestive system Flashcards
What do carbohydrates do for the body
Provide us with fuel to carry out reactions in the body they are made of units of sugar
What’s are lipids
There fats and oils which make up the most efficient energy store. Made up of 3 fatty acids and 1 glycerol
What are proteins used for
Used for building cells, tissues and enzymes made up of amino acids which can be differently arranged
What’s amylase
A carbohydrase produced in the salivary gland which breaks down carbohydrates/starch into sugars
What enzymes are produced in the small intestines
Protease and lipase
How is protease used in the stomach
It breaks down proteins into amino acids which can be absorbed into the blood
What enzymes are produced in the pancreas
Amylase, lipase, protease
What does lipase do to lipids
They break them down into fatty acids and glycerol
What’s the difference in ph levels between the stomach and small intestine
Stomach is acidic for protease enzymes and small intestine is alkaline for enzymes to work
Where is bile found
It’s made in the liver stored in the gall bladder and works in the small intestine
What does bile do
It neutralises acid from stomach in the small intestine also breaks down large drops of fat to droplets increasing SA this is called emulsification
How can an enzymes controlled reaction time increase
By increasing temp until optimum temp after this the enzyme’s protein structure is altered and enzyme is denatured the same with PH
How can enzymes be used again
As they are not used up in a chemical reaction so are unchanged
How do you test for sugar
- Use the Benedict’s test
- Put food sample in test tube
- Add Benedict’s solution to tube
- Heat up for 5 mins
- If no change a negative result
If blue - green little sugar present
If blue to red positive result
How do test for protein
- Use the biuret test
- Crush food sample up
- Put food sample into test tube
- Add biuret solution
5.shake gently to mix - If no change a negative result
If blue - lilac positive result
How to test for starch
- Use the iodine tests
- Crush food sample up
- Put food sample into test tube
- Add iodine solution
- Shake tube gently to mix
- If no change a negative result
If orange - blue/black positive result
How to test for lipids
- Use emulsion test
- Crush food sample up and place in test tube
- Add drops of distilled water
- And some ethanol
- Shake gently to mix
- If no change negative result
If milky white emulsion forms a positive result
What’s a buffer
A solution of a certain pH
Method to test effects of pH on enzymes
- Buffers with different pH’s placed in test tubes (independent variable)
- Amylase and starch added to test tube
- Every 30 secs tests each solution with iodine in a dimple tray
- When starch Brocken down iodine with stop turning black
5.Buffer with is closest pH to optimum will stop turning black the quicker
