B2.5 - Proteins - Their Functions And Uses Flashcards
What can proteins act as? (4)
- Hormones.
- Antibodies.
- Catalysts.
- Structural components of tissues e.g. muscles.
What is the name of molecules that fit with a specific enzyme?
Substrates.
How many reactions can each enzyme catalyse?
One.
What happens when an enzyme works at too high a temperature?
The bonds holding the enzyme together break, and it is now denatured.
What temperature do most enzymes in the human body work best at?
37 degrees.
What pH do most enzymes work best at?
7.
Which enzyme works best at pH 2 and why?
Pepsin, because it breaks down proteins in the stomach, which is highly acidic (because of the hydrochloride acid).
Digestive enzymes break down ___,___ molecules into ___,___ molecules.
Large, insoluble.
Small, soluble.
What does starch get broken down into and how?
Maltose and other sugars, by amylase.
What do proteins get broken down into and how?
Amino acids, by protease.
What do lipids (fats and oils) get broken down into and how?
Glycerol and fatty acids, by lipase.
Where is amylase produced? (3)
- Salivary glands.
- Pancreas.
- Small intestine.
Where is protease produced? (3)
- Stomach.
- Pancreas.
- Small intestine.
Where is lipase produced? (2)
- Pancreas.
2. Small intestine.
Where is bile produced?
The liver.
Bile is stored in the ___ ____ before being released into the ____ _____.
Gall bladder, small intestine.
What does bile do in the small intestine? (2)
- Because bile is alkaline, it can neutralise the hydrochloric acid from the stomach, which would have too high a pH for most enzymes to work in.
- Bile emulsifies fats, and therefore digestion is faster because the fat droplets have a greater surface area.
What pH conditions to enzymes in the small intestine work best in?
Alkaline.
What are proteases and lipases used for in the home?
Biological detergents, as they are able to digest the stains.
What is an advantage of biological detergents?
They are more effective at lower temperatures than other detergents.
What is a use of protease in industry?
In baby foods to ‘pre-digest’ the proteins.
What is a use of carbohydrase in industry?
To concert starch into sugar syrup.
What is a use of isomerase in industry?
To convert glucose syrup into fructose syrup, which is a lot sweeter and hence is used in smaller quantities in slimming foods.
What are the advantages of using enzymes in industry?
They are able to perform at normal temperatures and pressures, and therefore expensive equipment does not have to be bought.
What are the disadvantages of using enzymes in industry?
They become denatured at high temperatures, and many are expensive to produce.
What are protein molecules made from?
Large chains of amino acids.
