3.1.4.2 Many Proteins are Enzymes Flashcards
What do enzymes do in living cells
Control reactions
What do enzymes do
So what are they
Speed up reactions
Biological catalysts
What do enzymes not do to reactions
Cause then
2 advantages of enzymes
Can be used over + over
Effective in small amounts
What were enzymes discovered in in 1900
What type of enzyme
In yeast
Extracellular
What does the word ‘enzyme’ mean
‘In yeast’
How many different enzymes are there in human cells
40,000
What is each enzyme like to different chemical reactions
Specific
What do enzymes do to rate of reactions
Increase by up to 10(12) times
What would the speed of reactions not do without enzymes
Support life
What type of protein structure do enzymes have
Tertiary
Globular proteins
What’s an enzymes function determined by
It’s complex structure
Wheee does the reaction in an enzyme take place
In the active site
Only a few of what are involved in enzyme reactions
What type
Amino acids
Catalytic amino acids
What do catabolic reactions do
Break down
What do anabolic reactions do
Build up
What does the tertiary structure do in enzyme reactions
Brings them together
What binds in the active site
What does the rest of the protein do
The substrate
Acts as support
What do enzymes only bind with and control as they’re specific
Only bind with 1 substrate
Control only 1 reaction
What are the substrate and active site to each other
Complementary
What do enzymes ALWAYS form when they combine with their substrate
enzyme-substrate complexes
Why are enzyme-substrate complexes released as products
Due to their change in shape (after they bond)
Why can enzymes be re-used
As they aren’t altered or used up by reactions
Enzymes are energy efficient but what do they not do
What
Don’t last forever
As can be denatured/digested by protease
What do many enzymes also need to function
Other chemicals - coenzymes
What can slow down/stop enzyme function
Inhibitors
What inhibitor slows down enzyme function
Competitive
What inhibitor stops enzyme function
Permanent
Formula for enzyme function
Enzyme + substrate -> enzyme-substrate complex -> enzyme + products
How long does the enzyme-substrate complex last
Only temporarily while the substrate is sat in the active site
What are the 2 enzyme hypothesis’ s
Lock + key hypothesis
Induced fit hypothesis
What type of model is the lock + key hypothesis
What’s the active site like towards the substrate
Rigid
Active site is the inverse shape of the substrate - its complementary
How does the substrate form the enzyme-substrate complex in the lock + key hypothesis
The substrate fits into the precise shape (active site)
What does the lock+ key hypothesis not fully explain
The stabilisation of the enzyme - substrate complex
What’s the most generally accepted mechanism of action theory
Induced fit hypothesis