B3.4/B3.5 - Enzymes Flashcards
catalyst
speeds up chemical reaction
-doesn’t get used up
enzyme definition
-biological catalyst
-controls rate of chemical reactions
-large protein molecules
-speeds up process of digestion
Lock and key theory
-each enzyme reacts with a particular substrate
-amino acid chains are folded to create an active site
-allows substrate to bind to enzyme perfectly
active site
unique shape to bind specific substrate
-area of enzyme where substrate enters
-chemical reaction occurs here
lock and key theory process
-enzyme + reactant
=ezyme-reactant complex
=enzyme + products
Metabolic reactions
-control metabolism
metabolism
sum of all reactions taking place in a cell/body of an organism
Types of metabolic reactions enzymes catalyse
-building up large molecules from lots of different ones
-changing one molecule into another
-breaking down large molecules to smaller ones
Factors affecting enzyme action
-temp
-ph level
-enzyme concentration
-substrate concentration
-surface area
-pressure
optimum of enzymes
-particular temp or ph enzymes work best at
Denatured enzymes
-change of temp/ph that is beyond optimum = irreversible changes to shape
-changes active site = no longer functions
denatured meaning
-breakdown of molecular structure of a protein so it no longer functions
effect of ph on enzyme
-active site is made by forces between different parts of the protein molecule
-change in ph = change in forces = chnage in active site/shape
-enzyme becomes denatured
Adaptations of stomach for protease
-protease works best in acidic conditions
-stomach produces hydrochloric acid
How alkaline bile helps enzymes from pancreas/small intestine
-neutralises acid
-creates high ph for these enzymes to work well at
