Question 1

A plant has a unique photosynthetic pigment.The leaves of this plant appear to be reddish yellow.What wavelengths of visible light are being absorbed by this pigment?

Accepted Answer

A) red and yellow 
B) blue and violet 
C) green and yellow 
D) blue, green, and red 
E) green, blue, and yellow

Question 2

The light reactions of photosynthesis supply the Calvin cycle with

Accepted Answer

A) light energy. 
B) CO₂ and ATP. 
C) H₂O and NADPH. 
D) ATP and NADPH. 
E) sugar and O₂.

Question 3

Photorespiration occurs when rubisco reacts RuBP with

Accepted Answer

A) CO₂. 
B) O₂. 
C) glyceraldehyde 3-phosphate. 
D) 3-phosphoglycerate. 
E) NADPH.

Question 4

Cyclic electron flow may be photoprotective (protective to light-induced damage).Which of the following experiments could provide information on this phenomenon?

Accepted Answer

A) Use mutated organisms that can grow but that cannot carry out cyclic flow of electrons and compare their abilities to photosynthesize in different light intensities against those of wild-type organisms. 
B) Use plants that can carry out both linear and cyclic electron flow, or only one or another of these processes, and compare their light absorbance at different wavelengths and different light intensities. 
C) Use bacteria that have only cyclic flow and look for their frequency of mutation damage at different light intensities. 
D) Use bacteria with only cyclic flow and measure the number and types of photosynthetic pigments they have in their membranes. 
E) Use plants with only photosystem I operative and measure how much damage occurs at different wavelengths.

Question 5

In an experiment studying photosynthesis performed during the day,you provide a plant with radioactive carbon (¹⁴C)dioxide as a metabolic tracer.The ¹⁴C is incorporated first into oxaloacetate.The plant is best characterized as a

Accepted Answer

A) C₄ plant. 
B) C₃ plant. 
C) CAM plant. 
D) heterotroph. 
E) chemoautotroph.

Question 6

In a plant cell,where are the ATP synthase complexes located?

Accepted Answer

A) thylakoid membrane only 
B) plasma membrane only 
C) inner mitochondrial membrane only 
D) thylakoid membrane and inner mitochondrial membrane 
E) thylakoid membrane and plasma membrane

Question 7

Which of the following are products of the light reactions of photosynthesis that are utilized in the Calvin cycle?

Accepted Answer

A) CO₂ and glucose 
B) H₂O and O₂ 
C) ADP,℗ ᵢ, and NADP⁺ 
D) electrons and H⁺ 
E) ATP and NADPH

Question 8

Compared to C₃ plants,C₄ plants

Accepted Answer

A) can continue to fix CO₂ even at relatively low CO₂ concentrations and high oxygen concentrations. 
B) have higher rates of photorespiration. 
C) do not use rubisco for carbon fixation. 
D) grow better under cool, moist conditions. 
E) make a four-carbon compound, oxaloacetate, which is then delivered to the citric acid cycle in mitochondria.

Question 9

Some photosynthetic organisms contain chloroplasts that lack photosystem II,yet are able to survive.The best way to detect the lack of photosystem II in these organisms would be

Accepted Answer

A) to determine if they have thylakoids in the chloroplasts. 
B) to test for liberation of O₂ in the light. 
C) to test for CO₂ fixation in the dark. 
D) to do experiments to generate an action spectrum. 
E) to test for production of either sucrose or starch.

Question 10

In the process of carbon fixation,RuBP attaches a CO₂ to produce a six-carbon molecule,which is then split to produce two molecules of 3-phosphoglycerate.After phosphorylation and reduction produces glyceraldehyde 3-phosphate (G3P),what more needs to happen to complete the Calvin cycle?

Accepted Answer

A) addition of a pair of electrons from NADPH 
B) inactivation of RuBP carboxylase enzyme 
C) regeneration of ATP from ADP 
D) regeneration of RuBP 
E) regeneration of NADP⁺

Question 11

What compound provides the reducing power for Calvin cycle reactions?

Accepted Answer

A) ATP 
B) NADP⁺ 
C) NADPH 
D) NAD⁺ 
E) NADH

Question 12

The NADPH required for the Calvin cycle comes from

Accepted Answer

A) reactions initiated in photosystem I. 
B) reactions initiated in photosystem II. 
C) the citric acid cycle. 
D) glycolysis. 
E) oxidative phosphorylation.

Question 13

According to the endosymbiotic theory,the original chloroplast was a

Accepted Answer

A) chemisynthetic archaea. 
B) green algae. 
C) purple sulphur bacteria. 
D) mitochondria. 
E) photosynthetic prokaryote.

Question 14

Use the following figure and the compounds labelled A,B,C,D,and E to answer the following questions.
 
-If the carbon atom of the incoming CO₂ molecule is labelled with a radioactive isotope of carbon,which organic molecules will be radioactively labelled after one cycle?

Accepted Answer

A) C only 
B) B, C, D, and E 
C) C, D, and E only 
D) B and C only 
E) B and D only

Question 15

In thylakoids,protons travel through ATP synthase from the thylakoid space to the stroma.Therefore,the catalytic "knobs" of ATP synthase would be located

Accepted Answer

A) on the side facing the thylakoid space. 
B) on the ATP molecules themselves. 
C) on the pigment molecules of photosystem I and photosystem II. 
D) on the stromal side of the membrane. 
E) built into the centre of the thylakoid stack (granum).

Question 16

A flask containing photosynthetic green algae and a control flask containing water with no algae are both placed under a bank of lights,which are set to cycle between 12 hours of light and 12 hours of dark.The dissolved oxygen concentrations in both flasks are monitored.Predict what the relative dissolved oxygen concentrations will be in the flask with algae compared to the control flask.

Accepted Answer

A) The dissolved oxygen in the flask with algae will always be higher. 
B) The dissolved oxygen in the flask with algae will always be lower. 
C) The dissolved oxygen in the flask with algae will be higher in the light, but the same in the dark. 
D) The dissolved oxygen in the flask with algae will be higher in the light, but lower in the dark. 
E) The dissolved oxygen in the flask with algae will not be different from the control flask at any time.

Question 17

Some photosynthetic bacteria (e.g.,purple sulphur bacteria)have only photosystem I,whereas others (e.g.,cyanobacteria)have both photosystem I and photosystem II.Which of the following might this observation imply?

Accepted Answer

A) Photosystem II was selected against in some species. 
B) Photosynthesis with only photosystem I is more ancestral. 
C) Photosystem II may have evolved to be more photoprotective. 
D) Linear electron flow is more primitive than cyclic flow of electrons. 
E) Cyclic flow is more necessary than linear electron flow.

Question 18

The alternative pathways of photosynthesis using the C₄ or CAM systems are said to be compromises.Why?

Accepted Answer

A) Each one minimizes both water loss and rate of photosynthesis. 
B) C₄ compromises on water loss and CAM compromises on photorespiration. 
C) Both minimize photorespiration but expend more ATP during carbon fixation. 
D) CAM plants allow more water loss, while C₄ plants allow less CO₂ into the plant. 
E) C₄ plants allow less water loss but CAM plants allow more water loss.

Question 19

Which of the following statements is a correct distinction between autotrophs and heterotrophs?

Accepted Answer

A) Only heterotrophs require chemical compounds from the environment. 
B) Cellular respiration is unique to heterotrophs. 
C) Only heterotrophs have mitochondria. 
D) Autotrophs, but not heterotrophs, can nourish themselves beginning with CO₂ and other nutrients that are inorganic. 
E) Only heterotrophs require oxygen.

Question 20

Three "turns" of the Calvin cycle generate a "surplus" molecule of glyceraldehyde 3-phosphate (G3P).Which of the following is a consequence of this?

Accepted Answer

A) Formation of a molecule of glucose would require nine "turns." 
B) G3P more readily forms sucrose and other disaccharides than it does monosaccharides. 
C) Some plants would not taste sweet to us. 
D) The formation of sucrose and starch in plants involves assembling G3P molecules, with or without further rearrangements. 
E) Plants accumulate and store G3P.

Exam 10: Photosynthesis

A plant has a unique photosynthetic pigment.The leaves of this plant appear to be reddish yellow.What wavelengths of visible light are being absorbed by this pigment?

The light reactions of photosynthesis supply the Calvin cycle with

Photorespiration occurs when rubisco reacts RuBP with

Cyclic electron flow may be photoprotective (protective to light-induced damage) .Which of the following experiments could provide information on this phenomenon?

In an experiment studying photosynthesis performed during the day,you provide a plant with radioactive carbon (¹⁴C) dioxide as a metabolic tracer.The ¹⁴C is incorporated first into oxaloacetate.The plant is best characterized as a