Enzymes, proteins and catalysts Flashcards
What do different arrangements of amino acids give you?
Different proteins
What is a protein molecule made up off?
Long chains of small units called amino acids.
What do proteins do?
Proteins act as structural components of tissues, as hormones, as antibodies and as catalysts.
What is an amino acid?
A building block of protein
What is a catalyst?
A substance that speeds up a chemical reaction without it being changed itself.
Can you use catalysts over and over again?
Yes
What is an enzyme?
A protein molecule which acts as a biological catalyst. It changes the rate of chemical reactions without being affected itself at the end of the reaction.
In our body what control our chemical reaction rates?
Enzymes
When long chains of amino acids are folded what is produced?
A molecule with a specific shape.
What does this special shape allow?
It allows other molecules (substrates) to fit into the enzyme proteins. We call this the active site.
What is the active site?
The site on an enzyme where the reactants bind
What are enzymes involved in?
- Building large molecules from lots of smaller ones
- Changing one molecule into another
- Breaking down large molecules into smaller ones
Fill in the gaps:
Different enzymes catalyse ________ types of reactions.
Specific
Why do we need enzymes?
To speed up the reactions in our body
You need to build large molecules from smaller ones
You need to change certain molecules eg, one sugar into another.
Breaking down down insoluble food molecules into small soluble molecules.
Explain how enzymes work
The substrate of the reaction fits into the active site of the enzyme. Like a lock and key. Once it’s in place the enzyme and the substrate bind together. The reaction the takes place rapidly and the products are released from the surface of the enzyme.
What are enzymes make of?
Amino acid chains
Why does milk left in the sub go off quickly?
Enzymes in bacteria in the milk break down proteins that makes the milk go sour/bad.
Fill in the gaps:
As the temperature increases, the rate of enzyme controlled reaction __________ only up to temperatures of about _____.
Increases
40°C
What happens once the temperature is above 40?
The protein structure of the enzyme is affected and the long amino acid chains begin to unravel as a result the shape of the active sit changes. We say the enzyme has DENATURED.
At what temperature do most human enzymes work best ?
37°C
What is the optimum temperature?
When the reaction works as fast as possible
Where is pepsin found and what with, and at what pH does it work best at?
In the stomach with hydrochloric acid, best at pH 2
Where is amylase found and what’s it’s optimum pH?
In the small intestine with alkaline bile with an optimum of pH7.5.
What is your food made up of?
Large insoluble molecules that your body cannot absorb.
What needs to happen to the insoluble molecules?
They need to be broken down or digested to form smaller, soluble molecules. Then be absorbed by your cells.
What controls the chemical breakdown?
Digestive enzymes
How are digestive enzymes different?
Most of your enzymes work inside the cells of your body, controlling the rate of chemical reactions whereas digestive enzymes work outside your cells.
What is your gut?
A hollow muscular tube that squeezes your food. It helps to break up your food into small pieces with a large surface area for your enzymes to work on. It mixes your food with your digestive juices so that the enzymes come into contact with as much of the food as possible. The muscles of the guy move your food along from on area to the next.
What are the enzymes called that break down carbohydrates down?
Carbohydrases
Is starch one of the most common carbohydrates that you eat?
Yes
What are carbohydrates broken into and where?
They are broken down into sugars in your mouth and small intestine.
What is the name of the enzyme that breaks down starch in your gut?
Amylase
Where is amylase produced?
In your salivary glands
Where does the digestion of starch start?
In your mouth
