Enzymes And Digestion 2020 Jan Flashcards
Enzyme
An enzyme is a biological catalyst that speeds up reactions without being used or changed in the reaction itself
Enzymes are proteins
They can both build up (catabolic) and break down(anabolic ) molecules
What is the substance that the enzyme acts upon
The substrate
The New substance formed as a result of the reaction
Products
Amylase
Breaking down of the substrate complex starch molecules to simple glucose molecules
Amylase is the enzyme
Starch is the substrate
Glucose is the product
Protease
Protease is the enzyme
Protein is the substrate
Amino acids as the products
Lipase
Lipase is the enzyme
Fats (lipids) are the substrates
Fatty acids and glycerol are the products
Carbohydrase
Carbohydrase is the enzyme
Carbohydrates are the substrates
(Simple) sugars are the products
Reaction (1st step)
Enzyme and substrate molecules are constantly moving around (they have kinetic energy) and collide with each other
Reaction (2nd step)
When a substrate collides with the right enzyme, it fits exactly into the ACTIVE SITE (an area on the surface of the enzyme)
An enzyme / substrate complex forms
Reaction (3rd step )
The reaction takes place and the products are released from the active site
Reaction (4th n final step )
frees the active site for another substrate molecule to bind
Enzyme Inhibitors
There are molecules that fit loosely or partially into the active site of some enzymes. Such molecules are called inhibitors
Because while they occupy the active site of the enzyme, substrate molecules cannot enter and be broken down which leads to a reduced rate of reaction
Factors affecting enzyme controlled reactions
low temperature
Less Kinetic energy therefore less collisions
Factors affecting enzyme controlled reactions
rise in temp
As temp increase as does rate of reaction
Gains more kinetic energy
Therefore more collisions
Optimum temp is 37
Factors affecting enzyme controlled reactions
high temp
Chemical bonds holding enzyme together break
Enzyme is described as being DENATURED
