Enzymes and Digestion Flashcards
What is the structure of an enzyme?
Enzymes are an example of protein and because of this, they are formed of amino acids which fold up into specific shapes
What condition must be met for a chemical reaction to occur?
A certain amount of activation energy must be reached
Why are enzymes known as “biological catalysts?”
They reduce activation energy for a reaction to take place, which allows them to increase the rate of reaction
What part of an enzyme does a substrate molecule bind to?
The active site which has a specific shape and when the two bind together, a enzyme substrate complex is formed
What conditions must be met for a substrate to bind to an enzyme?
If the enzyme is complementary in shape and they collide with enough activation energy
What happens when an active site binds to the substrate?
A enzyme substate complex forms
What is the effect of temperature on the rate of reaction in enzymes?
- Increases the kinetic energy of the enz + sub molecules
- Causes them to move fast and more enzsub complexes to form
- This increases the rate of reaction
What happens to enzymes when the temperature is too high?
Enzymes denature and the rate of respiration falls
What is the effect of pH on the rate of reaction in enzymes?
The rate of reaction has an optimum pH. A pH too high or too low can denature the enzyme
What happens to an enzyme when it denatures?
The active site changes shape so it’s no longer complementary to the substrate
How does substrate concentration effect the rate of reaction in enzymes?
- Increased number of collisions between enz and sub molecules
- This results in more enzsub complexes to form increasing the RoR
Why does enzyme concentration eventually stop effecting the rate of reaction?
All of the enzymes active sites are full and no further enzsub complexes can form
What protein does milk contain?
Casein
What enzyme digests casein?
Trypsin (digests it into soluble amino-acids)
What is the definition of digestion?
The chemical/mechanical breakdown of food. The process converts large insoluble molecules into small soluble molecules which can be absorbed into the blood
What is mechanical digestion?
The physical breakdown of food, it creates a large surface area for enzymes to work on
What is chemical digestion?
The breaking down of large molecules into small soluble molecules by using enzymes
What is the difference between mechanical and chemical digestion?
Chemical digestion requires enzymes to break chemical bonds, while mechanical digestion does not break bonds and enzymes aren’t required
What process are food molecules absorbed?
Through diffusion and active transport
Why is it important that molecules are small and soluble?
So they are small enough to pass through the semi permeable membrane of the cells lining the illeum
What is peristalsis?
Peristalsis is when muscles in the gut contact and push food forward through the gut. Fiber makes this easier
What is the role of the mouth?
Mechanically breaks down food and forms food into balls
What is the composition of saliva?
The enzyme amylase, mucus and water
What is the role of the salivary gland?
Amylase converts starch to maltose
