Energy and Enzymes (Mid 2) Flashcards
Which example(s) below use(s) kinetic energy to perform work? (Choose all that apply)
Multiple answers:
Multiple answers are accepted for this question
a
Roasting marshmallows over a campfire
b
Water in an unused water pistol
c
Gas can full of gas
d
Unopened bag of chips
e
Water moving over a dam and moving a turbine
e
Water moving over a dam and moving a turbine
a
Roasting marshmallows over a campfire
Living organisms increase in complexity as they grow, resulting in a decrease in the entropy of an organism. How does this not break the second law of thermodynamics?
a
Living organisms do not obey the second law of thermodynamics, which states that entropy must increase with time.
b
As a consequence of growing, organisms cause a greater increase in entropy in their environment than the decrease in entropy associated with their growth.
c
Life obeys the second law of thermodynamics because the decrease in entropy as the organism grows is exactly balanced by an increase in the entropy of the universe.
d
Living organisms are able to transform energy into entropy.
b
As a consequence of growing, organisms cause a greater increase in entropy in their environment than the decrease in entropy associated with their growth.
Ice melts spontaneously at room temperature, even though the process has a positive ΔH (i.e. is endothermic). How is this possible?
a
The change in thermal energy is small, so melting still obeys the second law of thermodynamics.
b
The first law of thermodynamics does not apply to phase changes such as melting.
c
Water has a very high specific heat.
d
There is a large increase in entropy.
d
There is a large increase in entropy.
A solution of starch at room temperature does not readily decompose to form a solution of simple sugars because:
a
the hydrolysis of starch to sugar is endergonic
b
starch cannot be hydrolyzed in the presence of so much water
c
starch hydrolysis is nonspontaneous
d
the starch solution has less free energy than the sugar solution
e
the activation energy barrier for this reaction cannot easily be surmounted at room temperature
e
the activation energy barrier for this reaction cannot easily be surmounted at room temperature
Do you think the concentration of the substrate (in comparison to the concentration of the regulatory molecule) will be particularly important in competitive inhibition and/or allosteric regulation?
a
Concentration of substrate will be equally important in both
b
Concentration of substrate will be equally not important in both
c
Concentration of substrate will be very important in competitive inhibition, but not as important in allosteric regulation
d
Concentration of substrate will be very important in allosteric regulation, but not as important in competitive inhibition
c
Concentration of substrate will be very important in competitive inhibition, but not as important in allosteric regulation
Some of the drugs used to treat HIV patients are competitive inhibitors of the HIV reverse transcriptase enzyme. Unfortunately, the high mutation rate of HIV means that the virus rapidly acquires mutations with amino acid changes that make them resistant to these competitive inhibitors. Where in the reverse transcriptase enzyme would such amino acid changes most likely occur in drug-resistant viruses?
a
at a cofactor binding site
b
in or near the active site
c
at an allosteric site
d
A mutation would have the same affect anywhere in the protein structure
b
in or near the active site
A series of enzymes catalyze the reaction X → Y → Z → A. Product A binds to the enzyme that converts X to Y at a position far away from the enzyme’s active site. This binding decreases the activity of the enzyme.
With respect to the enzyme that converts X to Y, substance A functions as:
a
The substrate
b
A coenzyme
c
An allosteric inhibitor
d
A transition state
e
A competitive inhibitor
c
An allosteric inhibitor
