Quizzes

Question 1

Which electron carriers function in the citric acid cycle?
1) NADH and FADH2
2) NAD+ only
3) ADP and ATP
4) The electron transport chain

Answer 1

1

Question 2

Energy released by the electron transport chain is used to pump H+ ions into which location in eukaryotic cells?
1) Mitochondrial intermembrane space
2) Mitochondrial inner membrane
3) Mitochondrial Matric
4) Cytoplasm adjacent to the mitochondrial outer membrane

Answer 2

1

Question 3

Which of the following statements about the electron transport is true?
1) It consists of a series of redox reactions
2) It occurs in the cytoplasm of both prokaryotic and eukaryotic cells
3) It includes a series of hydrolysis reactions associated with mitochondrial membranes
4) It is driven by ATP hydrolysis

Answer 3

1

Question 4

Starting with one molecule of glucose, glycolysis results in the net production of which of the following sets of energy-containing products?
1) 6 CO2, 2 pyruvate, and 2 ATP
2) 2 NADH, 2 pyruvate, and 2 ATP
3) 4 NADH, 2 pyruvate, and 4 ATP
4) 2 NAD+, 2 pyruvate, and 2 ATP

Answer 4

2

Question 5

What is the electron acceptor in the following reactions?
Pyruvate + NADH+ H+ —> Lactate + NAD+
1) NADH
2) NAD+
3) Lactate
4) Pyruvate

Answer 5

4

Question 6

Starting with citrate, which of the following combinations of products would result from three acetyl CoA molecules entering the citric acid cycle?
1) 1 ATP, 2 CO2, 3 NADH, 1 FADH2
2) 3 ATP, 6 CO2, 9 NADH, 3 FADH2
3) 6 ATP, 6 CO2, 3 NADH, 12 FADH2
4) 3 ATP, 3 CO2, 3NADH, 3 FADH2

Answer 6

2

Question 7

What happens when electrons are passed from one atom to a more negative atom?
1) The more electronegative atom is reduced and energy is consumed
2) The more electronegative atom is reduced, and energy is released
3) The more electronegative atom is oxidized, and energy is released
4) The more electronegative atom is oxidized and energy is consumed

Answer 7

2

Question 8

Which of the following statements describes what happens to a molecule that functions as the electron donor in a redox or oxidation-reduction reaction?
1) It gains electrons and loses potential energy
2) It loses electrons and loses potential energy
3) It gains electrons and gains potential energy
4) It loses electrons and gains potential energy

Answer 8

2

Question 9

Which of the following statements best describes the primary role played by oxygen in cellular respiration?
1) It serves as the final acceptor for electrons from the electron transport chain
2) It serves as an acceptor for carbon, forming CO2 in the citric acid cycle
3) It oxidizes glucose to form two molecules of pyruvate
4) It yields energy in the form of ATP as it is passed down the electron transport chain transport chain

Answer 9

1

Question 10

Which of the following statements describes a primary function of both alcohol and lactic acid fermentation?
1) Oxidation of NADH to NAD+
2) Reduction of FAD to FADH2
3) Hydrolysis of ATP to ADP + Pi
4) Reduction of NAD+ to NADPH

Answer 10

1

Question 11

What is the primary purpose of the Calvin cycle?
1) To use NADPH to release carbon dioxide
2) To use carbon dioxide to make a simple sugar (G3P)
3) To transport RuBP out of the chloroplast
4) To split water and release oxygen

Answer 11

2

Question 12

Which of the following statements correctly describes a distinction between autotrophs and heterotrophs?
1) Only heterotrophs require oxygen.
2) Autotrophs, but not heterotrophs, can nourish themselves beginning with CO2 and other nutrients that are inorganic.
3) Cellular respiration is unique to heterotrophs.
4) Only heterotrophs have mitochondria.

Answer 12

2

Question 13

A spaceship is designed to support animal life for a multiyear voyage to the outer planets of the solar system. Plants will be grown to provide oxygen and to recycle carbon dioxide. Since the spaceship will be too far from the sun for photosynthesis, an artificial light source will be needed. Suppose a plant has a unique photosynthetic pigment and the leaves of this plant appear to be reddish yellow. What wavelengths of visible light are absorbed by this pigment?
1) Blue and Violet
2) Green and Yellow
3) Red and Yellow
4) Green and Red

Answer 13

1

Question 14

In which part of the chloroplast are chlorophyll molecules located?
1) thylakoid membranes
2) stroma
3) inner membrane
4) intermembrane space

Answer 14

1

Question 15

Which of the following events accompanies absorption of energy by chlorophyll molecules of the photosystem complex?
1) An electron is excited.
2) NADP+ is reduced to NADPH.
3) ATP is synthesized from the energy absorbed.
4) A molecule of water is split.

Answer 15

1

Question 16

The oxygen released by photosynthesis is produced by which of the following processes?
1) The electron transfer system of photosystem I
2) Chemiosmosis
3) The electron transfer system of photosystem II
4) Splitting water molecules

Answer 16

4

Question 17

Which of the following statements best describes the relationship between photosynthesis and cellular respiration?
1) Photosynthesis stores energy in complex organic molecules; cellular respiration releases energy from complex organic molecules.
2) Cellular respiration runs the biochemical pathways of photosynthesis in reverse.
3) Photosynthesis occurs only in plants; cellular respiration occurs only in animals.
4) Photosynthesis is catabolic; cellular respiration is anabolic.

Answer 17

1

Question 18

What happens to the free energy released as electrons are passed from photosystem II to photosystem I through a series of electron carriers?
1) It is used to phosphorylate NAD+ to NADPH.
2) It is used to establish and maintain a H+ gradient.
3) It is used to break down ATP through phosphorylation.
4) It excites electrons of the reaction center in photosystem I.

Answer 18

2

Question 19

In a plant, the reactions that produce oxygen (O2) take place _____.
1) during the light reactions only
2) oxygen (O2) is not made during photosynthesis
3) during the Calvin cycle only
4) during both the light reactions and Calvin cycle

Answer 19

1

Question 20

In the initial step in carbon fixation, a molecule of CO2 is attached to RuBP to produce a six-carbon molecule, which is immediately split to produce two molecules of 3-phosphoglycerate. After phosphorylation and reduction produce glyceraldehyde 3-phosphate (G3P), what more needs to occur to complete the Calvin cycle?
1) Addition of a pair of electrons from NADPH
2) Regeneration of RuBP
3) Regeneration of ATP from ADP
4) Regeneration of NADP+

Answer 20

2

Question 21

In the polymerization of DNA, a phosphodiester bond is formed between a phosphate group of the nucleotide being added and which of the following atoms or molecules of the last nucleotide in the polymer?
1) A nitrogen from the nitrogen-containing base
2) C6
3) The 5’ phosphate
4) The 3’ OH

Answer 21

4

Question 22

Which of the following enzymes functions in DNA replication to add nucleotides to the newly synthesized strand and serves to proofread to make sure the correct bases are being added?
1) Primase
2) Helicase
3) Ligase
4) DNA polymerase

Answer 22

4

Question 23

In E. coli, there is a mutation in a gene called dnaB that alters the helicase that normally acts at the origin of replication. Which of the following events would you expect to occur as a result of this mutation?
1) Replication will require a DNA template from another source
2) Replication will occur via RNA polymerase alone
3) Additional proofreading will occur
4) No replication fork will be formed

Answer 23

4

Question 24

In DNA replication, the resulting daughter molecules contain one strand of the original parental DNA and one new strand. What is the explanation for this phenomenon?
1) DNA replication is conservative
2) RNA synthesis is conservative
3) DNA replication is not conservative
4) DNA replication is semiconservative

Answer 24

4

Question 25

Which of the following statements correctly describes the difference between the leading and the lagging strands of DNA during DNA replication?
1) The leading strand is synthesized in the same direction as the movement of the replication fork, and the lagging strand is synthesized in the opposite direction.
2) The leading strand is synthesized at the same speed as the lagging strand
3) The leading strand is synthesized by adding nucleotides to the 3’ end of the growing strand, and the lagging strand is synthesized by adding nucleotides to the 5’ end
4) The lagging strand is synthesized continuously, whereas the leading strand is synthesized in short fragments that are ultimately stitched together.

Answer 25

1

Question 26

What is the overall product of DNA replication?
1) One mRNA copy of each gene sequence
2) Two identical DNA double helix copies
3) Four identical DNA double helix copies
4) Two identical mRNA copies of each gene sequence

Answer 26

2

Question 27

In E. coli, which enzyme catalyzes the elongation of a new DNA strand in the 5’ → 3’ direction?
1) Helicase
2) DNA ligase
3) Primase
4) DNA polymerase III

Answer 27

4

Question 28

3’ TCTGCTG 5’ what bases will be added to the primer as DNA replication proceeds?
1) 5’ AGACGAC 3’
2) 3’ GTCGTCT 5’
3) 5’CAGCAGA 3’
4) 3’ TCTGCTG 5’

Answer 28

1

Question 29

Which of the following enzymes functions in DNA replication to unwind and separate the two strands of DNA at the replication fork?
1) Ligase
2) Helicase
3) Primase
4) DNA polymerase

Answer 29

2

Question 30

You briefly expose bacteria undergoing DNA replication to radioactively labeled nucleotides. When you centrifuge the DNA isolated from the bacteria, the DNA separates into two classes. One class of labeled DNA includes very large molecules (thousands or even millions of nucleotides long), and the other includes short stretches of DNA (several hundred to a few thousand nucleotides in length). Which two classes of DNA do these different samples represent?
1) Lagging strands and okazaki fragments
2) Leading strands and RNA primers
3) Leading strands and okazaki fragments
4) Okazaki fragments and RNA primers

Answer 30

3