BIO TEST 4 - LECTURE 1 STUDY GUIDE (PT.2) Flashcards
Cells use proteins called ________ as catalysts to lower activation energy during chemical reactions. Fill in the blank.
Enzymes
What is a substrate?
Will attach to the active site of the enzyme
Changes it and then it’ll be a completely different component
What is the definition of the active site of an enzyme?
Accepting substance to go and do a reaction
When the substrate binds to the enzymes it creates a reaction
Location: (pocket or cleft in enzyme)
Know this enzyme cycle below. You will have to label the steps of this reaction if this question is chosen by Excel.
- the substrate consists of glucose and fructose
- the substrate binds to the active site and crates a substrate- enzyme complex
- the binding of the substrate causes the glucose- fructose bond to break.
- products are released, and the enzyme is free to bind with other substrates
What is the definition of an enzyme-substrate complex?
Substrate and enzyme are connected
Different chemical process take place inside the area
Substrate will bind to the actual enzyme
Chemical reaction will occur
What is the definition of a multienzyme?
Several enzymes are catalyzing different steps of reactions
Are associated in non-covalent bonded assemblies
Which is not an advantage of using multienzymes verses regular enzymes?
There are 3 main advantages:
Rate of any enzyme - It’ll collide much faster if it’s right next to another enzyme
Reacting substance - prevent side reactions
Minimal chances of something going wrong
________ are chemical components which assist in an enzyme’s function. ________ are when the cofactor is a non-protein organic molecules (i.e. vitamins). Fill in the blanks.
- Cofactors
- Coenzyme
For specific enzymes, what happens when a cofactor is not attached to its designed enzyme?
enzymes doesn’t mean they can carry out process all on their own
vitamin are big example of coenzymes because they get a chemical process going
Which statement explains how temperature and pH can affect enzymes?
increase temp. → increase rate of reaction
as pH value increases above or decreases below the optimum pH → enzyme activity decreases
What is the definition of an enzymatic inhibitor?
substance that binds to enzyme to decrease activity or stops it together
What is the difference between a competitive inhibitor and noncompetitive inhibitor?
Competitive Inhibitor: attaches to active site, it competes with substrate for the same active site
Noncompetitive Inhibitor: changes a shape of enzyme so it cannot bind to substrate, turns it off
What is the definition of an allosteric site of an enzyme?
chemical on or off switch that some enzymes have
What is the definition of either an (a) allosteric inhibitor or (b) allosteric activator?
Allosteric inhibitors: substrate binding is reduced or prevented
Allosteric activators: the affinity for the substrate increases
What is the definition of a biochemical pathway?
-Involves enzymes
-The product of one reaction becomes the substrate to the next reactant
