Deck 1: Introduction to the Chemistry of Life

Question 1

For the followin questions,consider the structure of the coenzyme NADP
Which arrow points at an anhydride bond?

A)A
B)B
C)C
D)D
E)E

Answer 1

A

Question 2

Matching

The organisms most likely to be found in high temperature environments would be ______.

A) phylogenetic
B) negative
C) H₂O
D) ΔH°
E) H – TS
F) halobacteria
G) open
H) entropy
I) flux
J) polymers
K) ΔG°´
L) thermophiles
M) nitrogen
N) positive

Answer 2

thermophiles

Question 3

Matching

During chemical evolution,small organic molecules condense to form more complex molecules called ______.

A) phylogenetic
B) negative
C) H₂O
D) ΔH°
E) H – TS
F) halobacteria
G) open
H) entropy
I) flux
J) polymers
K) ΔG°´
L) thermophiles
M) nitrogen
N) positive

Answer 3

polymers

Question 4

Matching

The symbol for free energy under standard biochemical conditions is ______.

A) phylogenetic
B) negative
C) H₂O
D) ΔH°
E) H – TS
F) halobacteria
G) open
H) entropy
I) flux
J) polymers
K) ΔG°´
L) thermophiles
M) nitrogen
N) positive

Question 5

Using phylogeny all living organisms can be divided into the following domains:

A)bacteria,eukarya,and vertebrate
B)archaea and eukarya
C)bacteria,eukarya,and archaea
D)eukarya and bacteria
E)none of the above

Question 6

Which of the following statements about hydrothermal vents is true?

A)The vents have temperatures as high as 800°C and emit H₂S and metal sulfides.
B)The vents have temperatures as high as 600°C and emit H₂S and metal nitrates.
C)The vents have temperatures as high as 400°C and emit H₂S and metal sulfides.
D)none of the above
E)all of the above

Question 7

Matching

The term used to indicate the degree of randomness within a system is ______.

A) phylogenetic
B) negative
C) H₂O
D) ΔH°
E) H – TS
F) halobacteria
G) open
H) entropy
I) flux
J) polymers
K) ΔG°´
L) thermophiles
M) nitrogen
N) positive

Question 8

Matching

The most abundant molecule in the human body is _____.

A) phylogenetic
B) negative
C) H₂O
D) ΔH°
E) H – TS
F) halobacteria
G) open
H) entropy
I) flux
J) polymers
K) ΔG°´
L) thermophiles
M) nitrogen
N) positive

Question 9

Matching

Gibbs free energy is defined as G = ______.

A) phylogenetic
B) negative
C) H₂O
D) ΔH°
E) H – TS
F) halobacteria
G) open
H) entropy
I) flux
J) polymers
K) ΔG°´
L) thermophiles
M) nitrogen
N) positive

Question 10

Matching

Living creatures can be described thermodynamically as ______ systems.

A) phylogenetic
B) negative
C) H₂O
D) ΔH°
E) H – TS
F) halobacteria
G) open
H) entropy
I) flux
J) polymers
K) ΔG°´
L) thermophiles
M) nitrogen
N) positive

Question 11

Which of the following developed during the evolution of eukaryotic cells from prokaryotic cells?

A)DNA
B)the cell membrane
C)nuclear membranes
D)ribosomes
E)proteins

Question 12

The atmosphere of prebiotic earth probably contained the following molecules:

A)H₂O,CO₂,N₂ ,CH₄,and NH₃.
B)H₂O,CO₂,CH₄,C₆H₁₂O₆, and NH₃.
C)H₂O,CO₂,CH₄,C₆H₁₂O₆, and COO^-CH₂NH⁺₃.
D)H₂O,CO₂,CH₄,COOHCH₂NH₃,and NH₃.
E)none of the above

Question 13

Matching

Spontaneous processes are characterized by a change in Gibbs free energy that is ______.

A) phylogenetic
B) negative
C) H₂O
D) ΔH°
E) H – TS
F) halobacteria
G) open
H) entropy
I) flux
J) polymers
K) ΔG°´
L) thermophiles
M) nitrogen
N) positive

Question 14

For the followin questions,consider the structure of the coenzyme NADP
Which arrow points at a glycosidic bond?

A)A
B)B
C)C
D)D
E)E

Question 15

For the followin questions,consider the structure of the coenzyme NADP
Which arrow points at an amide bond?

A)A
B)B
C)C
D)D
E)E

Question 16

Matching

Evolutionary relationships can be visualized using a ______ tree.

A) phylogenetic
B) negative
C) H₂O
D) ΔH°
E) H – TS
F) halobacteria
G) open
H) entropy
I) flux
J) polymers
K) ΔG°´
L) thermophiles
M) nitrogen
N) positive

Question 17

Matching

The organisms most likely to be found in a brine environment would be ______.

A) phylogenetic
B) negative
C) H₂O
D) ΔH°
E) H – TS
F) halobacteria
G) open
H) entropy
I) flux
J) polymers
K) ΔG°´
L) thermophiles
M) nitrogen
N) positive

Question 18

For the followin questions,consider the structure of the coenzyme NADP
Which arrow points at a phosphate ester bond?

A)A
B)B
C)C
D)D
E)E

Question 19

What are the four most abundant elements in a human body?

A)C,N,O,H
B)C,N,O,P
C)C,S,O,H
D)C,Na,O,H
E)none of the above

Question 20

In 1953,Urey and Miller carried out an experiment in which they subjected a mixture of H₂O,CH₄,NH₃,and H₂ to electrical discharges.Which of the following were among the products?

A)proteins
B)amino acids
C)nucleic acids
D)ribosomes
E)all of the above

Question 21

Which of the statements about viruses is not true?

A)Viruses are much simpler than cells.
B)Viruses are the simplest living organisms.
C)Viruses lack the necessary metabolic apparatus to reproduce.
D)Viruses are dependent on host cells.
E)All the statements are true.

Question 22

If gas molecules in an enclosed chamber are allowed to enter a second chamber,the resulting redistribution of gas molecules represents an increase in

A)enthalpy.
B)entropy.
C)force.
D)chemical potential.
E)all of the above

Question 23

Consider the reaction A + B $\leftrightarrow$ C + D.After reaching equilibrium at 25°C,the following concentrations of reactants and products were measured: [A] = 10 $\mu$ M,[B] = 15 $\mu$ M,[C] = 10 $\mu$ M,[D] = 10 $\mu$ M.Calculate $\Delta$ G°' for this reaction.

A)1000 J/mol
B)10 kJ/mol
C)1 J/mol
D)insufficient data to determine answer
E)none of the above

Question 24

Which of the following statements about the theories of (bio)chemical evolution is not true?

A)During chemical evolution,simple organic molecules (monomers)condensed to form more complex molecules (polymers)which then began to replicate based upon complementarity.
B)Margulis suggested that mitochondria and chloroplasts evolved from the symbiotic relationship between primordial prokaryotic and eukaryotic cells.
C)The first cells were probably formed when self-replicating systems were enveloped in membranous vesicles.
D)Oparin and Haldane demonstrated that by passing an electrical discharge through a vessel containing H₂O,CO₂,N₂,CH₄ and NH₃ some basic biological building blocks (like simple amino acids)could have formed abiotically in the earth's early atmosphere.
E)The RNA world hypothesis as proposed by Woese,Crick and Orgel states that RNA,instead of protein,was the first self replicating biochemical molecule that evolved because RNA could have stored genetic information and performed the catalytic roles necessary for primitive self-replication.

Question 25

Which of the following statement(s)is (are)not true?

A)Margulis proposed the endosymbiotic theory to explain the evolution of mitochondria and chloroplasts.
B)Woese proposed the "new" phylogenic tree that divides living organisms into the 3 domains of bacteria,archaea and eukarya based upon genetic relationships rather than obvious morphological similarities.
C)Urey and Miller conducted an experiment that involved sparking a mixture of NH₃,CH₄,H₂O and H₂ gases to yield amino acids,some of the fundamental building blocks of life.
D)All of the above are false.
E)All of the above are true.

Question 26

Which group of organisms is not prokaryotic?

A)Fungi
B)Archaea
C)Purple bacteria
D)Cyanobacteria
E)Methanococcus

Question 27

The term molecular weight is a term used by biochemists that refers to

A)the density of a particle.
B)a dimensionless quantity that is defined as the ratio of the mass of the particle to 1/12 the mass of a ¹²C atom.
C)Daltons divided by the mass of a hydrogen atom.
D)all of the above
E)none of the above

Question 28

The theory of evolution includes which of the following principles?

A)Evolution is not directed toward a specific goal.
B)Evolution is ongoing,and is constrained by its past.
C)Evolution requires some sloppiness for adaptation to changes.
D)A and B
E)A,B,and C

Question 29

Which of the following is a similarity between all prokaryotes and all eukaryotes?

A)Both contain DNA in a nucleus.
B)Both contain some of the same membrane bound cell organelles (like mitochondria,Golgi complexes,etc).
C)Both have a cytoskeleton.
D)All of the above are similarities between prokaryotes and eukaryotes.
E)None of the above is a similarity between prokaryotes and eukaryotes.

Question 30

Which of the following statements about eukaryotes is not true?

A)They contain organelles like mitochondria,chloroplasts,the endoplasmic reticulum and the nucleus.
B)They are usually 10 to 100 microns in diameter.
C)They can be either unicellular or multicellular.
D)They are also called archaea.
E)All of the above are true of eukaryotes.

Question 31

Phylogeny is

A)the science of biological classification based on gross morphology.
B)the science of biological classification based on the evolutionary relationships between organisms.
C)the science of biological classification based on reproductive strategies.
D)the branch of science that studies phyllopods.
E)none of the above

Question 32

Which cellular compartment or organelle is involved in the synthesis of proteins and lipids?

A)endoplasmic reticulum
B)lysosomes
C)peroxisomes
D)vacuoles
E)all of the above

Question 33

Change in enthalpy ( $\Delta$ H)is best defined as

A)the sum of heat absorbed and work done.
B)the heat transferred at constant pressure.
C)the pressure change at constant temperature.
D)the measure of disorder in a system.
E)none of the above

Question 34

The second law of thermodynamics states:

A)that spontaneous processes are characterized by the overall conversion of order to disorder.
B)that spontaneous processes are characterized by the conversion of work to force.
C)that nonspontaneous processes are characterized by the conversion of order to disorder.
D)that spontaneous processes are characterized by the conversion heat to pressure.
E)none of the above

Question 35

Lynn Margulis' Theory of Endosymbiosis is an explanation for the origin of

A)the endoplasmic reticulum.
B)the nucleus.
C)the mitochondria.
D)peroxisomes.
E)the Golgi apparatus.

Question 36

Which of the following statements concerning prokaryotes is false?

A)Prokaryotes are made up of two major groupings: the eubacteria and the archaea,which are as different from each other as from the eukaryotes.
B)Prokaryotes are generally much smaller than the eukaryotic cells.
C)Prokaryotes are one branch of the newer,more accurate phylogenic tree made up of prokarya,archaea and eukarya.
D)Prokaryotes do not have organelles.
E)None of the above is false.

Question 37

Taxonomy is

A)the science of biological classification based on gross morphology.
B)the science of biological classification based on the evolutionary relationships between organisms.
C)the science of biological classification based on reproductive strategies.
D)the branch of science that studies taxidermy.
E)none of the above

Question 38

Which three cellular components are present in both prokaryotes and eukaryotes?

A)ribosomes,chloroplasts,mitochondria
B)nucleus,ribosomes,RNA
C)RNA,DNA,ribosomes
D)endoplasmic reticulum,DNA,RNA
E)mitochondria,DNA,RNA

Question 39

Halophiles and thermophiles are

A)early versions of eukaryotic cells.
B)highly evolved organisms that thrive in their specific environments.
C)relatively inefficient and unevolved organisms.
D)more complex than eukaryotes.
E)extremely slow growing.

Question 40

The bulk of aerobic metabolism in eukaryotic cells takes place in

A)the endoplasmic reticulum.
B)the nucleus.
C)the mitochondria.
D)peroxisomes.
E)the Golgi apparatus.

Question 41

Carbohydrates,proteins,nucleotides,and nucleic acids are important groups of molecules found in living organisms.Which 6 elements do living organisms need to build these molecules?

Question 42

The reaction pyruvate + ATP $\leftrightarrows$ PEP + ADP is catalyzed by the enzyme pyruvate kinase.The $\Delta$ G°ꞌ for this reaction is 31.4 kJ/mol.Use this information to answer the following questions.
a.Does this reaction move forward (from left to right)or backward under standard state conditions? Explain you answer in one sentence.
b.Calculate the K_eq for this reaction at 25°C.
c.After the reaction has reached equilibrium at 25°C [ATP] = 5 mM,[ADP] = 0.5 mM,[pyruvate] = 0.2 mM.Calculate the concentration PEP.

Question 43

Calculate the $\Delta$ G for a reaction with $\Delta$ H = 20.kJ/mol and $\Delta$ S =20.J/K•mol,that is carried out at 27°C.

A)14 J/mol
B)140 J/mol
C)1400 J/mol
D)14,000 J/mol
E)none of the above

Question 44

For a reaction with $\Delta$ H = 23 kJ/mol and $\Delta$ S =22 J/K•mol,at 2°C,the reaction is:

A)spontaneous
B)nonspontaneous
C)at equilibrium
D)impossible to determine reactivity
E)none of the above

Question 45

A spontaneous process

A)occurs without the addition of free energy.
B)has a $\Delta$ G<0.
C)is exergonic.
D)is all of the above
E)is none of the above

Question 46

Consider a reaction in which $\Delta$ H = -20.kJ/mol and $\Delta$ S = 10.J/mol · K.
a.Calculate the $\Delta$ G for this reaction at 25°C.
b.Is the reaction spontaneous (explain your answer)?

Question 47

Living organisms

A)are closed systems.
B)maintain a steady state.
C)exist outside the laws of thermodynamics.
D)are all of the above
E)are none of the above

Question 48

An increase in disorder in the system

A)is required for a process to be spontaneous.
B)results in a decrease in entropy.
C)is characteristic of a system increasing in enthalpy.
D)results in the factor T $\Delta$ S being positive .
E)is found in every exergonic process.

Question 49

A van't Hoff plot

A)plots ln K_eq versus T
B)plots $\Delta$ K versus -T $\Delta$ S.
C)plots K_eq versus 1/T.
D)is a good method to determine $\Delta$ H° and $\Delta$ S°.
E)determines K_eq by plotting $\Delta$ H° versus 1/T.

Question 50

Phosphoglucomutase catalyses the reaction in which a phosphate group is transferred from the 1 carbon of glucose to the 6 carbon of glucose (G1P $\leftrightarrows$ G6P).A student at SDSU incubates a 0.2 M solution of glucose-1-phosphate overnight with a small amount of the enzyme.At equilibrium the concentration of glucose 1-phosphate is 9.0 × 10⁻³ M and the concentration of glucose 6-phosphate is 19.1 × 10⁻² M.
Calculate the equilibrium constant (K_eq)and the standard state free energy (∆G°')for this reaction at 25°C.

Question 51

Living organisms are classified thermodynamically as:

A)open systems.
B)closed systems.
C)isolated systems.
D)thermally isolated.
E)none of the above

Question 52

Explain in one or two sentences why scientists believe that all living organisms are related (that they have all evolved from a common ancestor)?

Question 53

An endergonic reaction with a ______ $\Delta$ H and a ______ $\Delta$ S can be changed into an exergonic reaction by decreasing the temperature.

A)positive,positive
B)positive,negative
C)negative,positive
D)negative,negative

Question 54

The $\Delta$ G° for the conversion of glucose 6-phosphate (G6P)to fructose 6-phosphate (F6P)is +1.7 kJ/mole.In a particular human cell the concentration G6P is 8.0 µM and the concentration F6P is 1.0 µM.Calculate the $\Delta$ G of the reaction as it occurs in this cell at 37°C?

A)−37 kJ/mol
B)−3.7 kJ/mol
C)0 kJ/mol
D)+7.1 kJ/mol
E)−0.6 kJ/mol

Question 55

Enzymes accelerate biochemical reactions by

A)decreasing the $\Delta$ G for the reactions.
B)increasing the $\Delta$ G for the reactions.
C)establishing a 'closed system' for each reaction.
D)promoting reaction pathways associated with a positive $\Delta$ G.
E)providing a more favorable pathway for the reactions.

Question 56

A reaction with a ______ $\Delta$ H and a ______ $\Delta$ S,will never be spontaneous.

A)positive,positive
B)positive,negative
C)negative,positive
D)negative,negative
E)none of the above