13) How Enzymes Work Flashcards
Enzyme Mechanism
Biological reactions take place in s___________ where enzymes and substrates are f________ to move around.
solution
free
Enzyme Mechanism
If the enzymes and substrates were in s______ form, they would never move and therefore never i__________. This is why the cytoplasm of the c___ is an a________ s_______ which contains d_________ substrates, enzymes and i____ freely moving around.
solid interact cell aqueous solution dissolved ions
Enzyme Mechanism
When a substrate collides with the correct enzyme, it binds with the active site, forming an e_________- s___________ - c___________.
The metabolic reaction then occurs.
enzyme-substrate-complex
Enzyme Mechanism
Once the metabolic reaction occurs an e________- p________ - c_________
is formed.
enzyme-product-complex
Enzyme Mechanism
After the e_______- p________ - c_________ is formed the product/products d______ from the enzyme, leaving the enzyme ready to c_________ the same reaction again.
enzyme-product-complex
detach
catalyse
The Lock and Key Hypothesis
Scientists used to think that e________ worked as a l______ and k___.
enzymes
lock and key
The Lock and Key Hypothesis
In this model each s________ is a key that only fits a specific lock, e_________.
substrate
enzyme
The Lock and Key Hypothesis
This model makes the assumption that the active site is r________ and p________
c__________ to the shape of its substrate.
rigid
permanently complementary
The Lock and Key Hypothesis
Scientists found that the a_______ s________ are f_______, and not rigid.
active sites
flexible
Induced Fit
Scientists observed that enzyme’s active sites are not always c________ to their s________ .
Because the shape of an enzyme’s active site is f________ and not r________, they came up with the new theory of i_________ f___.
complementary substrates flexible rigid induced fit
Induced Fit
In this model the enzyme’s a________ s______ is usually in a r_______ state and not c_______ to the shape of its s________.
active site
relaxed
complementary
substrate
Induced Fit
Binding with the substrate causes the active site to c_____ its s______ allowing the r_______ to be c_______.
So, the substrate binding i_______ the active site to change shape.
change shape
reaction
catalysed
induces
