aamc exam 2 chemical and physical foundations of b
Written for
MCAT
MCAT
Seller
Follow
cracker
Reviews received
Content preview
Aamc Exam 2 Chemical And Physical Foundations Of
Biological Systems Correct Answers
What expression gives the amount of light energy (in J per photon) that
is converted to other forms between the fluorescence excitation and
emission events?
A.
(6.62 × 10-34) × (3.0 × 108)
B.
(6.62 × 10-34) × (3.0 × 108) × (360 × 10-9)
C.
(6.62 × 10-34) × (3.0 × 108) × [1 / (360 × 10-9) - 1 / (440 × 10-9)]
D.
(6.62 × 10-34) × (3.0 × 108) / (440 × 10-9) Correct Answer-Solution:
The correct answer is C.
This is a Physics question that falls under the content category "How
light and sound interact with matter." The answer to this question is C
because the equation of interest is E = hf = hc/λ, where h = 6.62 × 10
−34 J ∙ s and c = 3 × 10 8 m/s. Excitation occurs at λe = 360 nm, but
fluorescence is observed at λf = 440 nm. This implies that an energy of
E = (6.62 × 10 −34) × (3 × 10 8) × [1 / (360 × 10 −9) − 1 / (440 × 10
−9)] J per photon is converted to other forms between the excitation and
fluorescence events. It is a Scientific Reasoning and Problem Solving
question because the question requires determining and using scientific
formulas to solve problems.
Which amino acid is found in greatest abundance in the active site of a
laccase?
,A.
Phe
B.
Tyr
C.
His
D.
Cys Correct Answer-Solution: The correct answer is C.
This is a Biochemistry question that falls under the content category
"Structure, function, and reactivity of biologically-relevant molecules."
The answer to this question is C because the five-membered imidazole
rings depicted in Figure 1 are associated with histidine, an amino acid
whose side chain is frequently encountered at the active site of
metalloenzymes. It is a Knowledge of Scientific Concepts and Principles
question because you must recognize the identity of an amino acid based
on the graphic depiction of its side chain.
The concentration of enzyme for each experiment was 5.0 μM. What is
kcat for the reaction at pH 4.5 with NO chloride added when Compound
3 is the substrate?
A.
2.5 × 10-2 s-1
B.
1.3 × 102 s-1
C.
5.3 × 103 s-1
,D.
7.0 × 105 s-1 Correct Answer-Solution: The correct answer is A.
This is a Biochemistry question that falls under the content category
"Principles of chemical thermodynamics and kinetics." The answer to
this question is A. The fact that the rate of product formation did not
vary over time for the first 5 minutes implies that the enzyme was
saturated with substrate. Under these conditions, kcat = Vmax/[E] =
(125 nM/s)/5.0 μM = 2.5 × 10-2 s-1. It is a Scientific Reasoning and
Problem Solving question because you must determine and then use a
scientific formula to solve a problem.
Absorption of ultraviolet light by organic molecules always results in
what process?
A.
Bond breaking
B.
Excitation of bound electrons
C.
Vibration of atoms in polar bonds
D.
Ejection of bound electrons Correct Answer-Solution: The correct
answer is B.
This is an Organic Chemistry question that falls under the content
category "How light and sound interact with matter." The answer to this
question is B. The absorption of ultraviolet light by organic molecules
always results in electronic excitation. Bond breaking can subsequently
result, as can ionization or bond vibration, but none of these processes
, are guaranteed to result from the absorption of ultraviolet light. It is a
Knowledge of Scientific Concepts and Principles question because you
must recognize a correct scientific principle.
The half-life of a radioactive material is:
A.
half the time it takes for all of the radioactive nuclei to decay into
radioactive nuclei.
B.
half the time it takes for all of the radioactive nuclei to decay into their
daughter nuclei.
C.
the time it takes for half of all the radioactive nuclei to decay into
radioactive nuclei.
D.
the time it takes for half of all the radioactive nuclei to decay into their
daughter nuclei. Correct Answer-Solution: The correct answer is D.
This is a Physics question that falls under the content category "Atoms,
nuclear decay, electronic structure, and atomic chemical behavior." The
answer to this question is D because the half-life of a radioactive
material is defined as the time it takes for half of all the radioactive
nuclei to decay into their daughter nuclei, which may or may not also be
radioactive. It is a Knowledge of Scientific Concepts and Principles
question because the question requires recognizing correct scientific
principles and related definitions.
A person is sitting on a chair as shown.
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller cracker. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for £12.25. You're not tied to anything after your purchase.