proteins - their functions and uses Flashcards
What are protein molecules made out of?
Protein molecules are made up of long chains of amino acids. These long chains are folded to produce a specific shape that enables other molecules to fit into the protein.
What do proteins act as?
- Structural components of tissues such as muscles
- Hormones
- Antibodies
- Catalysts.
What is a catalyst?
A catalyst is a substance which increases the speed of a reaction, without being changed or used up in the reaction.
What are enzymes?
Enzymes are biological catalysts, that are proteins.
What does high temperature do to an enzyme?
High temperatures change the shape. The shape of an enzyme is vital for the enzyme’s function. At high temperatures the enzyme denatures, enzymes in the body work best at around 37°C
What pH do enzymes work best at?
Different enzymes work best at different pH values
Why do you need enzymes break down big molecules into smaller ones?
Starch, proteins and fats are too big to pass through the walls of the digestive system. However sugars, amino acids, glycerol and fatty acids are smaller and therefore can pass easily through the walls of the digestive system.
What is amylase, where is it produced and what does it do?
The enzyme amylase is produced in the salivary glands, the pancreas and the small intestine. This enzyme catalyses the breakdown of starch into sugars .
What is protease, where is it produced and what does it do?
Protease enzymes are produced by the stomach, the pancreas and the small intestine. These enzymes catalyse the breakdown of proteins into amino acids in the stomach and the small intestine.
What is lipase, where is it produced and what does it do?
Lipase enzymes are produced by the pancreas and small intestine. These enzymes catalyse the breakdown of lipids (fats and oils) into fatty acids and glycerol in the small intestine.
How are the conditions like in the stomach?
It is a acidic as the stomach also produces hydrochloric acid. The enzymes in the stomach work most effectively in these acid conditions.
What is bile?
Bile is produced by the liver and stored in the gall bladder before being released into the small intestine.
What does bile do?
Bile neutralises the acid that was added to food in the stomach. Also it emulsifies fats (breaks fats into tiny droplets) - this gives a much bigger surface area to the fat for the enzyme lipase to work on- which makes its digestion faster.
Uses of enzymes at home.
- Biological detergents may contain protein-digesting and fat-digesting enzymes (proteases and lipases)
- Biological detergents are more effective at low temperatures than other types of detergents.
Uses of enzymes in industry.
- Proteases are used to ‘pre-digest’ the protein in some baby foods
- Carbohydrases are used to convert starch into sugar syrup
- Isomerase is used to convert glucose syrup into fructose syrup, which is much sweeter and therefore can be used in smaller quantities in slimming foods.
