Question 1

Plants convert nitrate into ammonia by using enzymes called ________

Accepted Answer

A)  peptidases.
B)  amylases.
C)  anhydrases.
D)  oxidases.
E)  reductases.

Question 2

Pacemakers implanted in the chests of patients with certain heart conditions are powered by a lithium/iodine PVP battery, where PVP represents polyvinylpyridine. The cell reaction and standard cell potential are given below. The standard reduction potential for Li/Li is 3.05 V. What species is oxidized in this reaction?  is 3.05 V. What species is oxidized in this reaction?   3.59 V A) Li B) I2 C) I2:PVP D) PVP E) LiI" class="answers-bank-image d-inline" rel="preload" > 3.59 V

Accepted Answer

A)  Li
B)  I2
C)  I2:PVP
D)  PVP
E)  LiI

Question 3

The active site of an enzyme typically contains ________

Accepted Answer

A)  an alkali metal.
B)  an alkaline earth metal.
C)  a transition metal.
D)  an actinide metal.
E)  a lanthanide metal.

Question 4

The concentration of a trace essential element in the body is typically in the range of ________ per gram of body mass.

Accepted Answer

A)  1g to 1 mg
B)  1g to 10 mg
C)  10g to 10 mg
D)  10g to 100 mg
E)  100g to 100 mg

Question 5

An essential biological element ________

Accepted Answer

A)  is any element detected in the organism.
B)  stimulates essential biological functions.
C)  is found in all organisms.
D)  has beneficial physiological effects, and its absence impairs function of the organism.
E)  is expensive.

Question 6

Which of the following is not a characteristic of a nonessential biological element?

Accepted Answer

A)  detected in the body but has no clear biological function
B)  has a stimulatory effect on biological functions
C)  is incorporated into biological compounds because it is similar to essential elements
D)  has clear biological functions
E)  organisms require them for survival

Question 7

The Mg2 ion plays a significant role in the human body by

Accepted Answer

A)  maintaining osmotic pressure.
B)  forming structure support for the body.
C)  transmitting nerve impulses.
D)  balancing ion flow in the bloodstream.
E)  participating in ATP hydrolysis and ADP phosphorylation.

Question 8

Selenocysteine is an amino acid that gets incorporated into proteins that serve as antioxidants. Evidence points to a need for a minimum daily dose of selenium of 55 g. How many moles of selenocysteine (C3H7NO2Se, 168 g /mol)  can be synthesized using this amount of selenium?

Accepted Answer

A)  3.3  107 mol
B)  7.0  107 mol
C)  3.3  104 mol
D)  7.0  104 mol
E)  3.7  107 mol

Question 9

Fluoridation to prevent tooth decay replaces ________ with fluoride in hydroxyapatite.

Accepted Answer

A)  hydroxide
B)  phosphate
C)  phosphide
D)  calcium
E)  water

Question 10

The concentration of sodium in the human body is approximately 1.5 mg/g of body mass. What is this concentration in ppm (parts per million) ?

Accepted Answer

A)  1.5  106 ppm
B)  1.5  103 ppm
C)  0.015 ppm
D)  1,500 ppm
E)  150 ppm

Question 11

The photosynthesis of carbohydrates from carbon dioxide and water is a redox reaction. Metalloenzymes containing manganese assist in the transfer of electrons. 
(1) Write the reaction equation for the photosynthetic production of glucose. 
(2) Identify the species that is oxidized. 
(3) Identify the species that is reduced.
(4) Identify the number of electrons transferred per mole of glucose produced.

Accepted Answer

(1)  
(2) Oxygen goes from F1F1F1S1F1F1F102 to 0, so it is oxidized.
(3) Carbon goes from F1F1F1S1F1F1F104 to 0, so it is reduced.
(4) To produce a molecule of glucose, 6 atoms of carbon must each receive 4 electrons to reduce their oxidation number from F1F1F1S1F1F1F104 to 0. So to produce a mole of glucose, 24 moles of electrons must be transferred.

Question 12

Which element, by mass, is most abundant in the human body?

Accepted Answer

A)  carbon
B)  oxygen
C)  hydrogen
D)  nitrogen
E)  calcium

Question 13

Stomach acid is 0.16 M HCl. What is the pH of stomach acid?

Accepted Answer

A)  0.80
B)  8.0
C)  (0.80) 
D)  0.69
E)  (8.0)  A

Question 14

Hearing aid batteries utilize a zinc/air electrochemical cell. The reduction half-reactions and standard reduction potentials for this cell are given below. What is the standard cell potential of zinc/air cell?  F1F1F1S1F1F1F101.249 V

Accepted Answer

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Question 15

The cation BiO is found in some over-the-counter antacids. Draw the Lewis structure of this cation that satisfies the octet rule for both atoms. Based on this Lewis structure, this cation has ________ of nonbonding electrons.

Accepted Answer

A)  a triple bond and two pairs
B)  a single bond and six pairs
C)  a double bond and three pairs
D)  a single bond and four pairs
E)  a quadruple bond and one pair

Question 16

Magnesium is found in which one of the following important biological molecules?

Accepted Answer

A)  chlorophyll
B)  hemoglobin
C)  cytochrome C
D)  ferredoxin
E)  adenosine triphosphate

Question 17

How much energy must be expended by a cell to transport 1 mole of sodium ions across a membrane with an electrochemical potential of 62 mV in order to maintain this potential?

Accepted Answer

A)  50 kJ
B)  260 kJ
C)  6.0 kJ
D)  250 kJ
E)  6,000 kJ

Question 18

The average concentration of calcium in the human body is 15 mg/g of body mass. What is the mass of calcium in the body of a person weighing 150 lb? (1 lb  454 g)

Accepted Answer

A)  1.0 lb
B)  0.023 lb
C)  23 lb
D)  100 lb
E)  2.3 lb E

Question 19

Ions need to move in and out of cells through cell membranes. Direct diffusion of ions through the lipid bilayer of the cell membrane is difficult because ions are not soluble in these nonpolar regions. Describe three mechanisms by which ions are transported through cell membranes.

Accepted Answer

Cell membranes have ion channels that ar...

Question 20

Which ion is important in transmitting nerve impulses?

Accepted Answer

A)  Na
B)  Mg2
C)  Fe2
D)  Zn2
E)  Li

Exam 21: The Main Group Elements: Life and the Periodic Table

Plants convert nitrate into ammonia by using enzymes called ________

Correct Answer
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Correct Answer
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The active site of an enzyme typically contains ________

Correct Answer
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The concentration of a trace essential element in the body is typically in the range of ________ per gram of body mass.

Correct Answer
verified

An essential biological element ________

Correct Answer
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Which of the following is not a characteristic of a nonessential biological element?

Correct Answer
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The Mg²^ ion plays a significant role in the human body by

Correct Answer
verified

Selenocysteine is an amino acid that gets incorporated into proteins that serve as antioxidants. Evidence points to a need for a minimum daily dose of selenium of 55 g. How many moles of selenocysteine (C₃H₇NO₂Se, 168 g /mol) can be synthesized using this amount of selenium?

Correct Answer
verified

Fluoridation to prevent tooth decay replaces ________ with fluoride in hydroxyapatite.

Correct Answer
verified

The concentration of sodium in the human body is approximately 1.5 mg/g of body mass. What is this concentration in ppm (parts per million) ?

Correct Answer
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Which element, by mass, is most abundant in the human body?

Correct Answer
verified

Stomach acid is 0.16 M HCl. What is the pH of stomach acid?

Correct Answer
verified
A

Hearing aid batteries utilize a zinc/air electrochemical cell. The reduction half-reactions and standard reduction potentials for this cell are given below. What is the standard cell potential of zinc/air cell? 1.249 V

Correct Answer
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View Answer

The cation BiO^ is found in some over-the-counter antacids. Draw the Lewis structure of this cation that satisfies the octet rule for both atoms. Based on this Lewis structure, this cation has ________ of nonbonding electrons.

Correct Answer
verified

Magnesium is found in which one of the following important biological molecules?

Correct Answer
verified

How much energy must be expended by a cell to transport 1 mole of sodium ions across a membrane with an electrochemical potential of 62 mV in order to maintain this potential?

Correct Answer
verified

The average concentration of calcium in the human body is 15 mg/g of body mass. What is the mass of calcium in the body of a person weighing 150 lb? (1 lb  454 g)

Correct Answer
verified
E

Ions need to move in and out of cells through cell membranes. Direct diffusion of ions through the lipid bilayer of the cell membrane is difficult because ions are not soluble in these nonpolar regions. Describe three mechanisms by which ions are transported through cell membranes.

Correct Answer
verified
Cell membranes have ion channels that ar...
View Answer

Which ion is important in transmitting nerve impulses?

Correct Answer
verified

Exam 21: The Main Group Elements: Life and the Periodic Table

Plants convert nitrate into ammonia by using enzymes called ________

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

The active site of an enzyme typically contains ________

Correct AnswerverifiedShow Answer

The concentration of a trace essential element in the body is typically in the range of ________ per gram of body mass.

Correct AnswerverifiedShow Answer

An essential biological element ________

Correct AnswerverifiedShow Answer

Which of the following is not a characteristic of a nonessential biological element?

Correct AnswerverifiedShow Answer

The Mg2 ion plays a significant role in the human body by

Correct AnswerverifiedShow Answer

Selenocysteine is an amino acid that gets incorporated into proteins that serve as antioxidants. Evidence points to a need for a minimum daily dose of selenium of 55 g. How many moles of selenocysteine (C3H7NO2Se, 168 g /mol) can be synthesized using this amount of selenium?

Correct AnswerverifiedShow Answer

Fluoridation to prevent tooth decay replaces ________ with fluoride in hydroxyapatite.

Correct AnswerverifiedShow Answer

The concentration of sodium in the human body is approximately 1.5 mg/g of body mass. What is this concentration in ppm (parts per million) ?

Correct AnswerverifiedShow Answer

Which element, by mass, is most abundant in the human body?

Correct AnswerverifiedShow Answer

Stomach acid is 0.16 M HCl. What is the pH of stomach acid?

Correct AnswerverifiedA

Hearing aid batteries utilize a zinc/air electrochemical cell. The reduction half-reactions and standard reduction potentials for this cell are given below. What is the standard cell potential of zinc/air cell? 1.249 V

Correct AnswerverifiedF...View AnswerShow Answer

The cation BiO is found in some over-the-counter antacids. Draw the Lewis structure of this cation that satisfies the octet rule for both atoms. Based on this Lewis structure, this cation has ________ of nonbonding electrons.

Correct AnswerverifiedShow Answer

Magnesium is found in which one of the following important biological molecules?

Correct AnswerverifiedShow Answer

How much energy must be expended by a cell to transport 1 mole of sodium ions across a membrane with an electrochemical potential of 62 mV in order to maintain this potential?

Correct AnswerverifiedShow Answer

The average concentration of calcium in the human body is 15 mg/g of body mass. What is the mass of calcium in the body of a person weighing 150 lb? (1 lb  454 g)

Correct AnswerverifiedE

Ions need to move in and out of cells through cell membranes. Direct diffusion of ions through the lipid bilayer of the cell membrane is difficult because ions are not soluble in these nonpolar regions. Describe three mechanisms by which ions are transported through cell membranes.

Correct AnswerverifiedCell membranes have ion channels that ar...View AnswerShow Answer

Which ion is important in transmitting nerve impulses?

Correct AnswerverifiedShow Answer

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The Mg²^ ion plays a significant role in the human body by

Correct Answer
verified

Selenocysteine is an amino acid that gets incorporated into proteins that serve as antioxidants. Evidence points to a need for a minimum daily dose of selenium of 55 g. How many moles of selenocysteine (C₃H₇NO₂Se, 168 g /mol) can be synthesized using this amount of selenium?

Correct Answer
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Correct Answer
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A

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View Answer

The cation BiO^ is found in some over-the-counter antacids. Draw the Lewis structure of this cation that satisfies the octet rule for both atoms. Based on this Lewis structure, this cation has ________ of nonbonding electrons.

Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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E

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Cell membranes have ion channels that ar...
View Answer

Correct Answer
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