Deck 11: Phototrophic Energy Metabolism: Photosynthesis

Question 1

Which of the following is not an accessory pigment used to absorb photons that cannot be captured by chlorophyll?

A)beta-carotene
B)a phycobilin
C)lutein
D)phycochlorophyll
E)phycocyanin

Answer 1

D

Question 2

The Emerson enhancement effect

A)was proposed by Robert Emerson in the 1980s.
B)states that there are three or four separate photoreactions.
C)is a synergistic phenomenon.
D)is the result of two distinct photosystems.
E)both choices C and D

Answer 2

E

Question 3

All of the following are true regarding anoxygenic photosynthesis except

A)a water molecule is split.
B)sulfide or thiosulfate can act as electron donors.
C)absorbed light energy is typically in the near ultraviolet and far red ranges of the light spectrum.
D)NADPH is regenerated by photoreduction.
E)it is a light-driven oxidation-reduction process.

Answer 3

A

Question 4

In a chloroplast,the stroma is the

A)cytochromes associated with the thylakoids.
B)stack of thylakoids.
C)region between in the inner and outer membranes.
D)connection between the grana.
E)central semifluid region.

Question 5

The ATP synthase complex in the thylakoid membrane

A)contains an embedded CF₁ component and a protruding CFo component.
B)is identical to the FoF₁ complex of mitochondria.
C)performs photophosphorylation in oxygenic phototrophs.
D)contains an assembly of hydrophobic polypeptides that function in ATP synthesis.
E)all of the above

Question 6

The proplastids associated with giving flowers and fruits their distinctive colors are the

A)chloroplasts.
B)elaioplasts.
C)amyloplasts.
D)chromoplasts.
E)plastids.

Question 7

Of the following plastids,which is not paired with the proper contents?

A)amyloplasts; amylase
B)chromoplasts; non-chlorophyll pigments
C)chloroplasts; chlorophyll
D)proteinoplasts; protein
E)elaioplasts; lipids

Question 8

What is the advantage to having various types of chlorophylls and accessory pigments for the photosynthetic process?

A)It allows for a variation in color amongst plants.
B)It allows for light in many wavelengths to be utilized for photosynthesis.
C)It allows light to be harvested specifically in a step-wise manner.
D)It shifts the equilibrium of photosynthesis toward the formation of products.
E)both choices C and D

Question 9

Carbon dioxide generally enters the plant through pores called

A)mesophyll.
B)stomata.
C)the cuticle.
D)connexons.
E)bacteriochlorophylls.

Question 10

Plastocyanin (PC)

A)is a mobile electron carrier.
B)is also called plastoquinol.
C)carries only a single electron at a time.
D)both choices A and C
E)choices A, B, and C

Question 11

Which of the following statements correctly characterizes the relationship between NADP⁺/NADPH and NAD⁺/NADH?

A)Both are used extensively during photosynthesis in oxygenic phototrophs.
B)Neither are helpful to oxygenic phototrophs.
C)NADP⁺/NADPH has an extra phosphate compared to NAD⁺/NADH.
D)NADP⁺/NADPH is used primarily for catabolic reactions.
E)Only NAD⁺/NADH is used to transport electrons and protons.

Question 12

Plastoquinol transfers electrons from

A)cytochrome b₆/f complex to coenymeQ.
B)photosystem II to photosystem I.
C)water to photosystem II.
D)light harvesting complex II to photosystem II.
E)cytochrome b₆/f to plastiquinone.

Question 13

NADP⁺ is the coenzyme of choice in ________ reactions,while NAD⁺ is the coenzyme of choice in ________ reactions.

A)anabolic; catabolic
B)catabolic; anabolic
C)metabolic; anabolic
D)anabolic; both catabolic and anabolic
E)both catabolic and anabolic; catabolic

Question 14

The process by which photosynthetic organisms use light energy for ATP production is known as

A)photorespiration.
B)photosynthesis.
C)phototaxis.
D)photophosphorylation.
E)photoligase

Question 15

NADPH contains the pentose sugar ________ and the nitrogenous base ________.

A)glucose; thymine
B)deoxyribose; cytosine
C)deoxyribose; nicotinamide
D)ribose; adenine
E)ribose; nicotinamide

Question 16

Photoheterotrophs are best described as organisms that obtain energy to make ATP

A)from organic compounds but use sunlight to produce carbon sources.
B)and organic compounds from sunlight.
C)from sunlight but cannot make organic compounds from CO₂.
D)from some forms of chemicals.
E)from organic compounds.

Question 17

Which of the following initially traps solar energy in the process of photosynthesis?

A)water
B)chlorophyll
C)triose phosphate
D)NADP⁺
E)ATP

Question 18

The endosymbiotic theory states that mitochondria originated from

A)a routine step in evolution.
B)the fusion of several prokaryotes.
C)purple bacteria entering and remaining in the cytoplasm of another cell.
D)the slow evolution of various organelles over millions of years, particularly during the time of the dinosaurs.
E)a long, intense period of lightning.

Question 19

Which of the following pigments is found exclusively in red algae?

A)chlorophyll a
B)chlorophyll c
C)lutein
D)phycoerythrin
E)β-carotene

Question 20

The relationship between photosystem I (PSI)and photosystem II (PSII)is correctly described by which of the following statements?

A)PSI absorbs only short wavelengths of light.
B)Electrons are excited by PSI or PSII, but not both.
C)PSI is designated P700, whereas PSII is designated P680.
D)The absorption maximum of PSII is 700 nm.
E)The absorption maximum of PSI is 680 nm.

Question 21

Biosynthesis of sucrose occurs in the

A)cytoplasm.
B)stroma.
C)thylakoid lumen.
D)intermembrane space.
E)stroma thylakoids.

Question 22

Which of the following compounds is not a source of electrons for anoxygenic photosynthesis?

A)SH⁻
B)S₂O₃²⁻
C)H₂O
D)succinate
E)All of the above are used.

Question 23

Bacteriochlorophyll differs from chlorophyll a and b in structure and function.Which of the following statements correctly contrasts these types of chlorophyll?

A)Bacteriochlorophyll has a porphyrin ring, whereas chlorophyll does not.
B)Chlorophyll has a phytol side chain, but bacteriochlorophyll does not.
C)Chlorophyll has a methyl group attached to the porphyrin ring, whereas bacteriochlorophyll has a formyl group.
D)Bacteriochlorophyll has a saturated carbon-carbon bond at one location in the porphyrin ring, whereas chlorophyll does not.
E)both choices A and D correctly contrast these types of chlorophyll.

Question 24

The transfer of energy from a photoexcited electron to another electron of an adjacent pigment molecule is known as

A)photoexcitation.
B)quantum leap.
C)photophosphorylation.
D)resonance energy transfer.
E)photorespiration.

Question 25

Which two triose phosphates are produced during the Calvin cycle and are the starting points for starch and sucrose synthesis?

A)3-phosphoglycerate and glyceraldehyde-3-phosphate
B)dihydroxyacetone phosphate and glyceraldehyde-3-phosphate
C)ribulose-1,5-bisphosphate and glycerol phosphate
D)dihydroxyacetone phosphate and glycerate-1,3-bisphosphate
E)3-phosphoglycerate and ribulose-1,5-bisphosphate

Question 26

Which of the following minerals are directly involved with light absorption in photosynthesis?

A)Zn
B)Mg
C)Fe
D)Ca
E)Na

Question 27

Which three organelles are involved in the glycolate pathway?

A)lysosome, chloroplast, rough endoplasmic reticulum
B)mitochondrion, nucleus, lysosome
C)peroxisome, smooth endoplasmic reticulum, chloroplast
D)peroxisome, chloroplast, mitochondrion
E)Golgi complex, peroxisome, lysosome

Question 28

In the Calvin cycle,the enzyme that catalyzes the capture of carbon dioxide and the formation of 3-phosphoglycerate is

A)phosphoglycerokinase.
B)ribulose bisphosphate carboxylase/oxygenase (rubisco).
C)triose phosphate isomerase.
D)phosphoribulokinase.
E)glyceraldehyde-3-phosphate dehydrogenase.

Question 29

The Calvin cycle occurs in the ________ region of the chloroplast.

A)stroma
B)grana
C)thylakoid lumen
D)thylakoid membrane
E)outer membrane

Question 30

Which of the following statements is correct regarding cyclic photosynthetic pathways?

A)Water molecules need to be split.
B)Both PSI and PSII are required.
C)Proton gradients are not formed.
D)No exogenous electron source is required.
E)all of the above

Question 31

Which of the following is not an essential feature of electron transfer from water to NADP⁺?

A)photosystem II complex
B)photosystem I complex
C)coenzyme Q
D)plastocyanin (PC)
E)cytochrome b₆/f complex

Question 32

The regeneration of what CO₂ acceptor molecule allows for continuous carbon assimilation in the Calvin cycle?

A)glyceraldehyde-3-phosphate
B)dihydroxyacetone phosphate
C)ribulose-1,5-bisphosphate
D)glycerate-1,3-bisphosphate
E)3-phosphoglycerate

Question 33

The Hatch-Slack cycle occurs in which of the following types of plants?

A)algae
B)C₃ plants
C)C₄ plants
D)tropical grasses
E)both choices C and D

Question 34

The plants referred to as C₃ and C₄ plants get this designation based on the number of carbons in the first detectable product of carbon dioxide fixation.The C₃ product is ________,whereas the C₄ product is ________.

A)glycerol; malate
B)triose phosphate; oxaloacetate
C)3-phosphoglycerate; malate
D)ribose; phosphoenolpyruvate
E)3-phosphoglycerate; oxaloacetate

Question 35

Which of the following statements regarding CAM plants is true?

A)Stomata are open during the day.
B)Malate is stored in large vacuoles.
C)CO₂ is transported directly into mesophyll cells.
D)They assimilate 25% less CO₂ than C₃ plants.
E)both choices B and C

Question 36

Which of the following products cannot be used in the Calvin cycle?

A)phosphoglycolate
B)NADPH
C)3-phosphoglycerate
D)CO₂
E)ribulose-1, 5-bisphosphate

Question 37

A house plant seems to be growing slowly and lacks its normal bright green color.You call a botanist for advice.She suggests that the plant may be deficient in magnesium (Mg²⁺).Why are these symptoms associated with Mg²⁺ deficiency?

A)Mg²⁺ is important in the structure of many amino acids.
B)Lack of Mg²⁺ in the soil allows pathogenic bacteria to grow.
C)Mg²⁺ is required before NADPH can function.
D)Mg²⁺ is an important component in chlorophyll.
E)Cytochromes require Mg²⁺ to function properly.

Question 38

Bacteria do not have organelles.How are they able to carry out photosynthesis?

A)They are parasites of plants that do have organelles.
B)They interact in a symbiotic relationship with eukaryotic plants.
C)They use their cell membrane to carry out photosynthesis.
D)DNA in the nucleoid captures solar energy.
E)70S ribosomes function as photosystems.

Question 39

Based upon the comparisons of anoxygenic and oxygenic photosythesis,the entry of oxygen into the atmosphere is most directly attributed to

A)photosystem I.
B)the Calvin cycle.
C)photoreactivation.
D)photosystem II.
E)bacteriorhodopsin.

Question 40

Which of the following statements accurately describes the Calvin cycle?

A)It is a carbon assimilation process.
B)In this process, carbon dioxide is reduced to organic sugars.
C)It occurs in the chloroplast stroma.
D)The Calvin cycle is a means of carbon fixation.
E)all of the above

Question 41

The energy transduction reactions of photosynthesis convert solar energy into chemical energy in the form of ________ and ________.

Question 42

Diatoms have both chorophyll a and chlorophyll ________.

Question 43

Chlorophyll is comprised of a central ________ containing a(n)________ ion and a(n)________ side chain.

Question 44

The Calvin cycle in C₃ plants occurs in ________ cells,whereas the Calvin cycle in C₄ plants occurs in the ________.

Question 45

The endosymbiont theory attempts to explain the evolutionary origin of eukaryotes.Describe this theory in a paragraph.Be sure to use these terms: semiautonomous organelles,symbiotic relationship,protoeukaryote,purple bacteria,cyanobacteria,mitochondria,and chloroplasts.

Question 46

Light behaves as a stream of discrete particles called ________,each carrying a ________ (indivisible packet)of energy.

Question 47

3-phosphoglycerate is to C₃ plants as ________ is to C₄ plants.

Question 48

If you needed to design an herbicide that was effective against a variety of different plants,what would you propose as a method to target individually CAM plants,C₄ plants,or a general herbicide?

Question 49

The glycolate pathway is also called ________,because CO₂ is released and oxygen is consumed in a light-dependent manner.

Question 50

When atmospheric carbon dioxide concentrations decrease,the ________ cycle gives C₄ plants an advantage over C₃ when it comes to fixation.

Question 51

The light-dependent generation of NADPH is referred to as ________.

Question 52

Green and purple bacteria are ________.This group of organisms removes electrons from sulfide,thiosulfate,and succinate to generate NADPH.

Question 53

Rubisco is an important enzyme in the Calvin cycle.It catalyzes the addition of carbon dioxide and water to ribulose-1,5-bisphosphate,which then forms two molecules of 3-phosphoglycerate.Rubisco acts as a carboxylase and is essential for carbon fixation.
a. Rubisco has an additional function.It can also function as an oxygenase.Why is this a problem for plants?
b. Rubisco has a much lower affinity for oxygen than for carbon dioxide.Why is the oxygenase activity still a problem for plants?
c. What is (are)the product(s)of the reaction when rubisco acts as an oxygenase?
d. How does the plant deal with the product of the oxygenase reaction?
e. The oxygenase activity of rubisco is particularly a problem for plants in arid environments.Can you explain why?
f. What strategies do plants in arid environments use to deal with this problem?

Question 54

________ proteins stabilize the arrangement of the chlorophyll within a photosystem and modify the absorption spectra of specific chlorophyll molecules.

Question 55

________ (PC)is a copper-containing protein that,like plastoquinol,is a mobile electron carrier.

Question 56

________ (CAM)plants open their stomata only at night to minimize water loss.

Question 57

Some herbicides,such as paraquat,work by causing the oxidation of NADPH to NADP. Although this is a potent herbicide,it also is toxic to humans,particularly when inhaled. How does paraquat interfere with photosynthesis and thus act as an herbicide? How might paraquat be causing toxicity for human cells?

Question 58

Why do tree leaves turn colors in autumn?