What role does a transcription factor play in a signal transduction pathway?

What role does a transcription factor play in a signal transduction pathway?

A. By binding a plasma membrane receptor it initiates a cascade
B. It relays a signal from the cytoplasm to the plasma membrane
C. It activates relay proteins
D. By binding to DNA it triggers the transcription of a specific gene
E. It is a plasma membrane protein that binds signal molecules

Answer: D

A toxin that inhibits the production of GTP would interfere with the function of a signal transduction pathway that is initiated by the binding of a signal molecule to _____ receptors.

A toxin that inhibits the production of GTP would interfere with the function of a signal transduction pathway that is initiated by the binding of a signal molecule to _____ receptors.

A- intracellular

B-steroid

C- ion-channel

D- G-protein-linked

E- receptor tyrosine kinase






Answer: D

Lipid-soluble signal molecules, such as testosterone, cross the membranes of all cells but affect only target cells because

Lipid-soluble signal molecules, such as testosterone, cross the membranes of all cells but affect only target cells because 

A)only target cells retain the appropriate DNA segments.
B) intracellular receptors are present only in target cells.
C) most cells lack the Y chromosome required.
D) only target cells possess the cytosolic enzymes that transduce the testosterone.
E) only in target cells is testosterone able to initiate the phosphorylation cascade leading to activated transcription factor.

Answer: B

Protein phosphorylation is commonly involved with all of the following except

Protein phosphorylation is commonly involved with all of the following except

A) regulation of transcription by extracellular signal molecules.
B) enzyme activation.
C) activation of G protein-coupled receptors.
D) activation of receptor tyrosine kinases.
E) activation of protein kinase molecules.

Answer: C

Which observation suggested to Sutherland the involvement of a second messenger in epinephrine's effect on liver cells?

Which observation suggested to Sutherland the involvement of a second messenger in epinephrine's effect on liver cells? 

A) Enzymatic activity was proportional to the amount of calcium added to a cell-free extract.
B) Receptor studies indicated that epinephrine was a ligand.
C) Glycogen breakdown was observed only when epinephrine was administered to intact cells.
D) Glycogen breakdown was observed when epinephrine and glycogen phosphorylase were combined.
E) Epinephrine was known to have different effects on different types of cells.

Answer: C

The activation of receptor tyrosine kinases is characterized by

The activation of receptor tyrosine kinases is characterized by 

A) dimerization and phosphorylation.
B) IP3 binding.
C) a phosphorylation cascade.
D) GTP hydrolysis.
E) channel protein shape change.

Answer: A

Binding of a signaling molecule to which type of receptor leads directly to a change in distribution of ions on opposite sides of the membrane?

Binding of a signaling molecule to which type of receptor leads directly to a change in distribution of ions on opposite sides of the membrane? 

A) receptor tyrosine kinase
B) G protein-coupled receptor
C) phosphorylated receptor tyrosine kinase dimer
D) ligand-gated ion channel
E) intracellular receptor

Answer: D

Phosphorylation cascades involving a series of protein kinases are useful for cellular signal transduction because

Phosphorylation cascades involving a series of protein kinases are useful for cellular signal transduction because 

A) they are species specific.
B) they always lead to the same cellular response.
C) they amplify the original signal manyfold.
D) they counter the harmful effects of phosphatases.
E) the number of molecules used is small and fixed.

Answer: C

If an adult person has a faulty version of the human-analog to ced-4 ofthe nematode, which of the following might more likely result?

If an adult person has a faulty version of the human-analog to ced-4 ofthe nematode, which of the following might more likely result? 

A) neurodegeneration
B) activation of a developmental pathway found in the worm but not in humans
C) a form of cancer in which there is insufficient apoptosis
D) webbing of fingers or toes
E) excess skin exfoliation

Answer: C

Human caspases can be activated by

Human caspases can be activated by 

A) irreparable DNA damage or protein misfolding.
B) infrequency of cell division.
C) high concentrations of vitamin C.
D) a death-signaling ligand being removed from its receptor.
E) electron transport.

Answer: A

The main proteases involved in apoptosis are

The main proteases involved in apoptosis are 

A) ced-3 and ced-4.
B) inactive.
C) cytochromes.
D) caspases.
E) G proteins.

Answer: D

Why has C. elegans proven to be a useful model for understanding apoptosis?

Why has C. elegans proven to be a useful model for understanding apoptosis? 

A) The animal has very few genes, so that finding those responsible is easier than in a more complex organism.
B) The nematode undergoes a fixed and easy-to-visualize number of apoptotic events during its normal development.
C) This plant has a long-studied aging mechanism that has made understanding its death just a last stage.
D) While the organism ages, its cells die progressively until the whole organism is dead.
E) All of its genes are constantly being expressed so allof its proteins are available from each cell.

Answer: B

The termination phase of cell signaling requires which of the following?

The termination phase of cell signaling requires which of the following? 

A) removal of the receptor
B) activation of a different set of relay molecules
C) converting ATP to camp
D) reversing the binding of signal molecule to the receptor
E) apoptosis

Answer: D

What are scaffolding proteins?

What are scaffolding proteins? 

A) ladder-like proteins that allow receptor-ligand complexes to climb through cells from one position to another
B) microtubular protein arrays that allow lipid-soluble hormones to get from the cell membrane to the nuclear pores
C) large molecules to which several relay proteins attach to facilitate cascade effects
D) relay proteins that orient receptors and their ligands in appropriate directions to facilitate their complexing
E) proteins that can reach into the nucleus of a cell to affect transcription

Answer: C

The use of beta 2 antagonist drugs may be useful in asthma because

The use of beta 2 antagonist drugs may be useful in asthma because 

A) they may increase constriction of the skeletal muscle of the chest wall.
B) they may increase heart rate and therefore allow the patient to get more oxygen circulated.
C) they may dilate the bronchioles by relaxing their smooth muscle.
D) they may override the beta blockers that the patient is already taking.
E) they may obstruct all G protein-mediated receptors.

Answer: C

As humans, we have receptors for two kinds of beta adrenergic compounds such as catecholamines. Cardiac muscle cells have beta 1 receptors that promote increased heart rate. Some drugs that slow heart rate are called beta blockers. Smooth muscle cells, however, have beta 2 receptors which mediate muscle relaxation. Blockers of these effects are sometimes used to treat asthma. The description above illustrates which of the following?

As humans, we have receptors for two kinds of beta adrenergic compounds such as catecholamines. Cardiac muscle cells have beta 1 receptors that promote increased heart rate. Some drugs that slow heart rate are called beta blockers. Smooth muscle cells, however, have beta 2 receptors which mediate muscle relaxation. Blockers of these effects are sometimes used to treat asthma. The description above illustrates which of the following? 

A) Just because a drug acts on one type of receptor does not mean that it will act on another type.
B) Beta blockers can be used effectively on any type of muscle.
C) Beta adrenergic receptors must be in the cytosol if they are going to influence contraction and relaxation.
D) The chemical structures of the beta 1 and beta 2 receptors must have the same active sites.

Answer: A

Which of the substances below is a protein that can hold several other relay proteins as it binds to an activated membrane receptor?

Which of the substances below is a protein that can hold several other relay proteins as it binds to an activated membrane receptor? 

A) active transcription factor
B) third messenger
C) ligand
D) scaffolding protein
E) protein kinase





Answer: D

A drug designed to inhibit the response of cells to testosterone would almost certainly result in which of the following?

A drug designed to inhibit the response of cells to testosterone would almost certainly result in which of the following? 

A) lower cytoplasmic levels of cAMP
B) an increase in receptor tyrosine kinase activity
C) a decrease in transcriptional activity of certain genes
D) an increase in cytosolic calcium concentration
E) a decrease in G-protein activity

Answer: C

One inhibitor of cGMP is Viagra. It provides a signal that leads to dilation of blood vessels and increase of blood in the penis, facilitating erection. cGMP is inhibited, therefore the signal is prolonged. The original signal that is now inhibited would have

One inhibitor of cGMP is Viagra. It provides a signal that leads to dilation of blood vessels and increase of blood in the penis, facilitating erection. cGMP is inhibited, therefore the signal is prolonged. The original signal that is now inhibited would have 

A) hydrolyzed cGMP to GMP.
B) hydrolyzed GTP to GDP.
C) phosphorylated GDP.
D) dephosphorylated cGMP.
E) removed GMP from the cell.

Answer: A

Which of the following is a correct association?

Which of the following is a correct association? 

A) kinase activity and the addition of a tyrosine
B) phosphodiesterase activity and the removal of phosphate groups
C) GTPase activity and hydrolysis of GTP to GDP
D) phosphorylase activity and the catabolism of glucose
E) adenylyl cyclase activity and the conversion of cAMP to AMP

Answer: C

Which of the following statements is true?

Which of the following statements is true?

A) When signal molecules first bind to receptor tyrosine kinases, the receptors phosphorylate a number of nearby molecules.

B) In response to some G-protein-mediated signals, a special type of lipid molecule associated with the plasma membrane is cleaved to form IP3 and calcium.

C) In most cases, signal molecules interact with the cell at the plasma membrane and then enter the cell and eventually the nucleus.

D) Toxins such as those that cause botulism and cholera interfere with the ability of activated G proteins to hydrolyze GTP to GDP, resulting in phosphodiesterase activity in the absence of an appropriate signal molecule.

E) Protein kinase A activation is one possible result of signal molecules binding to G protein- linked receptors.

Answer: E

An inhibitor of which of the following could be used to block the release of calcium from the endoplasmic reticulum?

An inhibitor of which of the following could be used to block the release of calcium from the endoplasmic reticulum? 

A) tyrosine kinases
B) serine/threonine kinases
C) phosphodiesterase
D) phospholipase C
E) adenylyl cyclase

Answer: D

If a pharmaceutical company wished to design a drug to maintain low blood sugar levels, one approach might be to

If a pharmaceutical company wished to design a drug to maintain low blood sugar levels, one approach might be to 

A) design a compound that blocks epinephrine receptor activation.
B) design a compound that inhibits cAMP production in liver cells.
C) design a compound to block G-protein activity in liver cells.
D) design a compound that inhibits phosphorylase activity.
E) All of the above are possible approaches.

Answer: E

Caffeine is an inhibitor of phosphodiesterase. Therefore, the cells of a person who has recently consumed coffee would have increased levels of

Caffeine is an inhibitor of phosphodiesterase. Therefore, the cells of a person who has recently consumed coffee would have increased levels of

A) phosphorylated proteins.
B) GTP.
C) cAMP.
D) adenylyl cyclase.
E) activated G proteins.

Answer: C

Adenylyl cyclase has the opposite effect of which of the following?

Adenylyl cyclase has the opposite effect of which of the following? 

A) protein kinase
B) protein phosphatase
C) phosphodiesterase
D) phosphorylase
E) GTPase

Answer: C

An inhibitor of phosphodiesterase activity would have which of the following effects?

An inhibitor of phosphodiesterase activity would have which of the following effects? 

A) block the response of epinephrine
B) decrease the amount of cAMP in the cytoplasm
C) block the activation of G proteins in response to epinephrine binding to its receptor
D) prolong the effect of epinephrine by maintaining elevated cAMP levels in the cytoplasm
E) block the activation of protein kinase A

Answer: D

Which of the following most likely would be an immediate result of growth factor binding to its receptor?

Which of the following most likely would be an immediate result of growth factor binding to its receptor?

A) protein kinase activity
B) adenylyl cyclase activity
C) GTPase activity
D) protein phosphatase activity
E) phosphorylase activity

Answer: A

Which of the following would be inhibited by a drug that specifically blocks the addition of phosphate groups to proteins?

Which of the following would be inhibited by a drug that specifically blocks the addition of phosphate groups to proteins? 

A) G-protein-linked receptor signaling
B) ligand-gated ion channel signaling
C) adenylyl cyclase activity
D) phosphatase activity
E) receptor tyrosine kinase activity

Answer: E

The toxin of Vibrio cholerae causes profuse diarrhea because it

The toxin of Vibrio cholerae causes profuse diarrhea because it 

A) modifies a G protein involved in regulating salt and water secretion.
B) decreases the cytosolic concentration of calcium ions, making the cells hypotonic to the intestinal cells.
C) binds with adenylyl cyclase and triggers the formation of cAMP.
D) signals inositol trisphosphate to become a second messenger for the release of calcium.
E) modifies calmodulin and activates a cascade of protein kinases.

Answer: A

Which of the following describes cell communication systems?

Which of the following describes cell communication systems? 

A) Cell signaling evolved more recently than systems such as the immune system of vertebrates.
B) Communicating cells are usually close together.
C) Most signal receptors are bound to the outer membrane of the nuclear envelope.
D) Lipid phosphorylation is a major mechanism of signal transduction.
E) In response to a signal, the cell may alter activities by changes in cytosol activity or in transcription of RNA.

Answer: E

The general name for an enzyme that transfers phosphate groups from ATP to a protein is

The general name for an enzyme that transfers phosphate groups from ATP to a protein is 

A) phosphorylase.
B) phosphatase.
C) protein kinase.
D) ATPase.
E) protease.

Answer: C

Which of the following is the best explanation for the inability of an animal cell to reduce the Ca2+ concentration in its cytosol compared with the extracellular fluid?

Which of the following is the best explanation for the inability of an animal cell to reduce the Ca2+ concentration in its cytosol compared with the extracellular fluid?

A) blockage of the synaptic signal
B) loss of transcription factors
C) insufficient ATP levels in the cytoplasm
D) low oxygen concentration around the cell
E) low levels of protein kinase in the cell

Answer: C

Sutherland discovered that epinephrine

Sutherland discovered that epinephrine 

A) signals bypass the plasma membrane of cells.
B) lowers blood glucose by binding to liver cells.
C) interacts with insulin inside muscle cells.
D)interacts directly with glycogen phosphorylase.
E) elevates the cytosolic concentration of cyclic AMP.

Answer: E

In general, a signal transmitted via phosphorylation of a series of proteins

In general, a signal transmitted via phosphorylation of a series of proteins

A) brings a conformational change to each protein.
B) requires binding of a hormone to a cytosol receptor.
C) cannot occur in yeasts because they lack protein phosphatases.
D) requires phosphorylase activity.
E) allows target cells to change their shape and therefore their activity.

Answer: A

The receptors for a group of signaling molecules known as growth factors are often

The receptors for a group of signaling molecules known as growth factors are often 

A) ligand-gated ion channels.
B) G-protein-linked receptors.
C) cyclic AMP.
D) receptor tyrosine kinases.
E) neurotransmitters.

Answer: D

Chemical signal pathways

Chemical signal pathways 

A) operate in animals, but not in plants.
B) are absent in bacteria, but are plentiful in yeast.
C) involve the release of hormones into the blood.
D) often involve the binding of signal molecules to a protein on the surface of a target cell.
E) use hydrophilic molecules to activate enzymes.

Answer: D

One of the major categories of receptors in the plasma membrane reacts by forming dimmers, adding phosphate groups, then activating relay proteins. Which type does this?

One of the major categories of receptors in the plasma membrane reacts by forming dimmers, adding phosphate groups, then activating relay proteins. Which type does this? 

A) G protein-linked receptor
B) ligand-gated ion channels
C) steroid receptors
D) receptor tyrosine kinases

Answer: D

Which is true of transcription factors?

Which is true of transcription factors? 

A) They regulate the synthesis of DNA in response to a signal.
B) Some transcribe ATP into cAMP.
C) They initiate the epinephrine response in animal cells.
D) They control which genes are expressed.
E) They are needed to regulate the synthesis of lipids in the cytoplasm.

Answer: D

Testosterone functions inside a cell by

Testosterone functions inside a cell by 

A) acting as a signal receptor that activates ion-channel proteins.

B) binding with a receptor protein that enters the nucleus and activates specific genes.

C) acting as a steroid signal receptor that activates ion-channel proteins.

D) becoming a second messenger that inhibits adenylyl cyclase.

E) coordinating a phosphorylation cascade that increases glycogen metabolism.

Answer: B

Which of the following are chemical messengers that pass through the plasma membrane of cells & have receptor molecules in the cytoplasm?

Which of the following are chemical messengers that pass through the plasma membrane of cells & have receptor molecules in the cytoplasm?

A. Insulin
B. Testosterone
C. cAMP
D. Epinephrine

Answer: B

Up to 60% of all medicines used today exert their effects by influencing what structures in the cell membrane?

Up to 60% of all medicines used today exert their effects by influencing what structures in the cell membrane? 

A) tyrosine-kinases receptors
B) ligand-gated ion channel receptors
C) growth factors
D) G proteins
E) cholesterol

Answer: D

Membrane receptors that attach phosphates to specific amino acids in proteins are

Membrane receptors that attach phosphates to specific amino acids in proteins are 

A) not found in humans.
B) called receptor tyrosine-kinases.
C) aclass of GTP G-protein signal receptors.
D) associated with several bacterial diseases in humans.
E) important in yeast mating factors that contain amino acids.

Answer: B

G proteins and G-protein-linked receptors

G proteins and G-protein-linked receptors 

A) are found only in animal cells, and only embedded in or located just beneath the cell's membrane.

B) are found only in bacterial cells, embedded in the cell's plasma membrane only.

C) are thought to have evolved very early, because of their similar structure and function in a wide variety of modern organisms.

D) probably evolved from an adaptation of the citric acid cycle.

E) are not widespread in nature and were unimportant in the evolution of eukaryotes.

Answer: C

Thyroid hormones bind to _____ receptors.

Thyroid hormones bind to _____ receptors.

A. G-protein-linked
B. tyrosine-kinase
C. plasma membrane ion-channel
D. intracellular
E. steroid

Answer: D

What would be true for the signaling system in an animal cell that lacks the ability to produce GTP?

What would be true for the signaling system in an animal cell that lacks the ability to produce GTP? 

A) It would not be able to activate and inactivate the G protein on the cytoplasmic side of the plasma membrane.
B) It could activate only the epinephrine system.
C) It would be able to carry out reception and transduction, but would not be able to respond to a signal.
D) Only A and C are true.
E) A, B, and C are true.

Answer: A

Of the following, a receptor protein in a membrane that recognizes a chemical signal is most similar to

Of the following, a receptor protein in a membrane that recognizes a chemical signal is most similar to

A) the active site of an allosteric enzyme in the cytoplasm that binds to a specific substrate.
B) RNA specifying the amino acids in a polypeptide.
C) a particular metabolic pathway operating within a specific organelle.
D) an enzyme with an optimum pH and temperature for activity.
E) genes making up a chromosome.

Answer: A

Which of the following is (are) true of ligand-gated ion channels?

Which of the following is (are) true of ligand-gated ion channels? 

A) They are important in the nervous system.
B) They lead to changes in sodium and calcium concentrations in cells.
C) They open or close in response to a chemical signal.
D) Only A and B are true.
E) A, B, and C are true.

Answer: E

A small molecule that specifically binds to another molecule, usually a larger one

A small molecule that specifically binds to another molecule, usually a larger one 

A) is called a signal transducer.
B) is called a ligand.
C) is called a polymer.
D) seldom is involved in hormonal signaling.
E) usually terminates a signal reception.

Answer: B

Synaptic signaling between adjacent neurons is like hormone signaling in which of the following ways?

Synaptic signaling between adjacent neurons is like hormone signaling in which of the following ways? 

A) It sends its signal molecules through the blood.

B) It sends its signal molecules quite a distance.

C) It requires calcium ions.

D) It requires binding of a signaling molecule to a receptor.

E) It persists over a long period.

Answer: D

When a cell releases a signal molecule into the environment and a number of cells in the immediate vicinity respond, this type of signaling is

When a cell releases a signal molecule into the environment and a number of cells in the immediate vicinity respond, this type of signaling is 

A) typical of hormones.
B) autocrine signaling.
C) paracrine signaling.
D) endocrine signaling.
E) synaptic signaling.

Answer: C

The process of transduction usually begins

The process of transduction usually begins 

A) when the chemical signal is released from the alpha cell.

B) when the signal molecule changes the receptor protein in some way.

C) after the target cell divides.

D) after the third stage of cell signaling is completed.

E) when the hormone is released from the gland into the blood.

Answer: B

From the perspective of the cell receiving the message, the three stages of cell signaling are

From the perspective of the cell receiving the message, the three stages of cell signaling are

A) the paracrine, local, and synaptic stages.

B) signal reception, signal transduction, and cellular response.

C) signal reception, nucleus disintegration, and new cell generation.

D) the alpha, beta, and gamma stages.

E) signal reception, cellular response, and cell division.

Answer: B

Paracrine signaling

Paracrine signaling 

A) involves secreting cells acting on nearby target cells by discharging a local regulator into the extracellular fluid.

B) requires nerve cells to release a neurotransmitter into the synapse.

C) occurs only in paracrine yeast cells.

D) has been found in plants but not animals.

E) involves mating factors attaching to target cells and causing production of new paracrine cells.

Answer: A

What could happen to the target cells in an animal that lack receptors for local regulators?

What could happen to the target cells in an animal that lack receptors for local regulators?

A- They could develop normally in response to neurotransmitters instead.

B- Hormones would not be able to interact with target cells.

C- They could divide but never reach full size.

D- They would not be able to multiply in response to growth factors from nearby cells.

E- They could compensate by receiving nutrients via an a factor.

Answer: D

In the yeast signal transduction pathway, after both types of mating cells have released the mating factors and the factors have bound to specific receptors on the correct cells,

In the yeast signal transduction pathway, after both types of mating cells have released the mating factors and the factors have bound to specific receptors on the correct cells,

A- the cell membranes fall apart, releasing the mating factors that lead to new yeast cells.

B- the cells then produce the a factor and the factor.

C- one cell nucleus binds the mating factors and produces a new nucleus in the opposite cell.

D- a growth factor is secreted that stimulates mitosis in both cells.

E- binding induces changes in the cells that lead to cell fusion.

Answer: E

Which of the following does not occur during the Calvin Cycle?

Which of the following does not occur during the Calvin Cycle?

A. carbon fixation
B. oxidation of NADPH
C. release of oxygen
D. regeneration of the CO2 acceptor
E. consumption of ATP








Answer: C

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

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

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

Answer: D

Which process is most directly driven by light energy?

Which process is most directly driven by light energy?

A. creation of a pH gradient by pumping protons across the thylakoid membrane
B. carbon fixation in the stroma
C. reduction of NADP+ molecules
D. removal of electrons from chlorophyll molecules
E. ATP synthesis







Answer: D

How is photosynthesis similar in C4 and CAM plants?

How is photosynthesis similar in C4 and CAM plants?

A. In both cases, only photosystem I is used
B. Both types of plants make sugar without the Calvin Cycle
C. In both cases, rubisco is not used to fix carbon initially
D. Both types of plants make most of their sugar in the dark
E. In both cases, thylakoids are not involved in photosynthesis







Answer: C

In mechanism, photophosphorylation is most similar to

In mechanism, photophosphorylation is most similar to 

A. substrate-level phosphorylation in glycolysis
B. oxidative phosphorylation in cellular respiration
C. the Calvin Cycle
D. carbon fixation
E. reduction of NADP+

Answer: B

Which of the following sequences correctly represents the flow of electrons during photosynthesis?

Which of the following sequences correctly represents the flow of electrons during photosynthesis?

A. NADPH-> O2-> CO2
B. H2O-> NADPH-> Calvin cycle
C. NADPH-> chlorophyll-> Calvin cycle
D. H2O-> photosystem I-> photosystem II
E. NADPH-> ETC-> O2






Answer: B

The light reactions of photosynthesis supply the Calvin cycle with

The light reactions of photosynthesis supply the Calvin cycle with 

A. Light energy
B. CO2 and ATP
C. H2O and NADPH
D. ATP and NADPH
E. Sugar and O2






Answer: D

If plant gene alterations cause the plants to be deficient in photo respiration, what would most probably occur?

If plant gene alterations cause the plants to be deficient in photo respiration, what would most probably occur?

A. Cells would carry on more photosynthesis
B. Cells would carry on the Calvin cycle at a much slower rate
C. Less ATP would be generated
D. There would be more light-induced damage to the cells
E. More sugars would be produced

Answer: C

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

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

A. Each one minimizes both water lose and rate of photosynthesis
B. C4 compromises on water loss and CAM compromises on photo respiration
C. Each one minimizes photorespiration and optimized the Calvin cycle
D. CAM plants allow more water lose, whileC4 plants allow less CO2 into the plant
E. C4 plants allow less water loss but CAM plants but allow more water lose

Answer: C

Photo respiration lowers the efficiency of photosynthesis by preventing the formation of

Photo respiration lowers the efficiency of photosynthesis by preventing the formation of

A. Carbon dioxide molecule
B. 3-phosphoglycerate molecules
C. ATP molecules
D. Ribulose biphosphate molecules
E. RuBP carboxylase molecules

Answer: B

CAM plants keep stomata closed in daytime, thus reducing loss of water. They can do this because they

CAM plants keep stomata closed in daytime, thus reducing loss of water. They can do this because they 

A. Fix CO2 into organic acids during the night
B. Fix CO2 into sugars in the bundle-sheath cells
C. Fix CO2 into pyruvate in the mesophyll cells
D. Use the enzyme phosphofructokinase, which out competes rubisco for CO2
E. Use photosystem I and II at night

Answer: A

Why are C4 plants able to photosynthesize with no apparent photo respiration?

Why are C4 plants able to photosynthesize with no apparent photo respiration?

A. They do not participate in the Calvin cycle
B. They use PEP carboxylasr to initially fix CO2
C. They are adapted to cold, wet climates
D. They conserve water more efficiently
E. They exclude oxygen from their tissues

Answer: B

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 florist into oxaloacetate. The plant is best characterized as a

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 florist into oxaloacetate. The plant is best characterized as a 

A. C4 plant
B. C3 plant
C. CAM plant
D. Heterotroph
E. Chemoautotroph

Answer: A

In which cell would you expect photo respiration?

In which cell would you expect photo respiration?

A. Cell I
B. Cell II
C. cell I at night
D. Cell II at night
E. Neither cell I not cell II







Answer: B

Referring to figure 10.3 oxygen would inhibit the CO2 fixation reactions in

Referring to figure 10.3 oxygen would inhibit the CO2 fixation reactions in

A. Cell I only
B. Cell II only
C. Neither cell I or cell II
D. both cell I and cell II
E. cell I during the night and cell II during the day

Answer: B

Which of the following statements is true concerning Figure 10.3?

Which of the following statements is true concerning Figure 10.3?

A it represents cell processes involved in C4 photosynthesis
B. It represents the type of cell structures found in CAM plants
C. It represents as adaption that maximizes photo respiration
D. It represents a C3 photosynthetic system
E. It represents a relationship between plant cells that photosynthesize and those that cannot

Answer: A

The pH of the inner thylakoid space has been measured, as have the pH of the stroma and of the cytosol of a particular plant cell. Which, if any, relationship would you expect to find?

The pH of the inner thylakoid space has been measured, as have the pH of the stroma and of the cytosol of a particular plant cell. Which, if any, relationship would you expect to find?

A. The pH within the thylakoid is less than that of the stroma
B. The pH of the stroma is higher than that of the other two measurements
C. The pH of the stroma is higher than that of the thylakoid space but lower than that of the cytosol
D. The pH of the thylakoid space is higher than that anywhere else in the cell
E. There is no consistent relationship

Answer: A

In metabolic processes of cell repairs room and photosynthesis, prosthetic groups such as heme and iron-sulfur complexes are encountered. What do they do?

In metabolic processes of cell repairs room and photosynthesis, prosthetic groups such as heme and iron-sulfur complexes are encountered. What do they do?

A. Donate electrons
B. Act as reducing agents
C. Acts as oxidizing agents
D. Transport protons within the mitochondria and chloroplasts
E. Both oxidize and reduce during electron transport

Answer: E

Which molecule(s) of the Calvin cycle is/are most like molecules found in glycolysis?

Which molecule(s) of the Calvin cycle is/are most like molecules found in glycolysis?

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





Answer: D

If the carbon atom of the incoming CO2 molecule is labeled with a radioactive isotope of carbon, where will the radioactivity be measurable after one cycle?

If the carbon atom of the incoming CO2 molecule is labeled with a radioactive isotope of carbon, where will the radioactivity be measurable after one cycle?

A. In C only
B. In E only
C. In C,D,and E
D. In A,B, and C
E. In B and C





Answer: B

If ATP used by this plant labeled with radioactive phosphorus, in which molecules will the radioactivity be measurable after one "turn" of the cycle?

If ATP used by this plant labeled with radioactive phosphorus, in which molecules will the radioactivity be measurable after one "turn" of the cycle?

A. In B only
B. In B and C only
C. In B,C, and D only
D. In B and E only
E. In B,C,D, and E







Answer: E

In the process of carbon fixation, RuBP attached a CO2 to produce a 6 carbon molecule, which is split in two. After phosphorylation and reduction, what more needs to happen in the Calvin cycle?

In the process of carbon fixation, RuBP attached a CO2 to produce a 6 carbon molecule, which is split in two. After phosphorylation and reduction, what more needs to happen in the Calvin cycle?

A. Addition of a pair of electron from NADPH
B. inactivation of RuBP caroxylase enzyme
C. Regeneration of ATP fro ADP
D. regeneration of rubisco
E. A gain of NADPH

Answer: D

The sugar that results from three "turns" of the Calvin cycle is glyceraldehyde-3-phosphate (G3P). Which of the following is a consequence of this

The sugar that results from three "turns" of the Calvin cycle is glyceraldehyde-3-phosphate (G3P). Which of the following is a consequence of this

A. Formation of a molecule of glucose would require 9 "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 starch in plants involves assembling many G3P molecules, with or without further rearrangements
E. G3P is easier for the plant to store

Answer: D

For the following questions, compare the light reactions with the Calvin cycle of photosynthesis in plants. Requires glucose

For the following questions, compare the light reactions with the Calvin cycle of photosynthesis in plants.
Requires glucose

A. Light reactions alone
B. The Calvin cycle alone
C. Both the light reactions and the Calvin cycle
D. Neither the light reactions nor the Calvin cycle
E. Occurs in the chloroplast but is not part of photosynthesis

Answer: D

For the following questions, compare the light reactions with the Calvin cycle of photosynthesis in plants. Requires CO2

For the following questions, compare the light reactions with the Calvin cycle of photosynthesis in plants.
Requires CO2

A. light reactions alone
B. The Calvin cycle alone
C. Both the light reactions and the Calvin cycle
D. Neither the light reactions nor the Calvin cycle
E. Occurs in the chloroplast but is not part of photosynthesis

Answer: B

For the following questions, compare the light reactions with the Calvin cycle of photosynthesis in plants. Produced three-carbon sugars

For the following questions, compare the light reactions with the Calvin cycle of photosynthesis in plants.
Produced three-carbon sugars

A. Light reactions alone
B. The Calvin cycle alone
C. Both the light reactions and the Calvin cycle
D. Neither the light reactions nor the Calvin cycle
E. Occurs in the chloroplast but is not part of photosynthesis

Answer: B

For the following questions, compare the light reactions with the Calvin cycle of photosynthesis in plants. Produced NADPH

For the following questions, compare the light reactions with the Calvin cycle of photosynthesis in plants.
Produced NADPH 

A. light reactions alone
B. The Calvin cycle alone
C. Both the light reactions and the Calvin cycle
D. Neither the light reactions nor the Calvin cycle
E. Occurs in the chloroplast but is not part of photosynthesis

Answer: A

For the following questions, compare the light reactions with the Calvin cycle of photosynthesis in plants. Produced NADH

For the following questions, compare the light reactions with the Calvin cycle of photosynthesis in plants.
Produced NADH

A. light reactions only
B. The Calvin cycle only
C. Both the light reactions and the Calvin cycle
D. Neither the light reactions nor the Calvin cycle
E. Occurs in the chloroplast but is not part of photosynthesis

Answer: D

For the following questions, compare the light reactions with the Calvin cycle of photosynthesis in plants. Requires ATP

For the following questions, compare the light reactions with the Calvin cycle of photosynthesis in plants.
Requires ATP 

A. Light reactions only
B. The Calvin cycle alone
C. Both the light reactions and the Calvin cycle
D. Neither the light reactions nor the Calvin cycle
E. Occurs in the chloroplast but is not part of photosynthesis







Answer: B

For the following questions, compare the light reactions with the Calvin cycle of photosynthesis in plants. Produced molecular oxygen(O2)

For the following questions, compare the light reactions with the Calvin cycle of photosynthesis in plants.
Produced molecular oxygen(O2)

A. Light reactions alone
B. The Calvin cycle alone
C. Both the light reactions and the Calvin cycle
D. Neither the light reactions nor the Calvin cycle
E. Occurs in the chloroplast but is not part of photosynthesis

Answer: A

What is the primary function of the Calvin cycle?

What is the primary function of the Calvin cycle?

A. Use ATP to release carbon dioxide
B. Use NADPH to release carbon dioxide
C. Split water and release oxygen
D. Transport RuBP out of the chloroplast
E. Synthesize simple sugars from carbon dioxide

Answer: E

Where do the enzymatic reactions of the Calvin cycle take place?

Where do the enzymatic reactions of the Calvin cycle take place?

A. Stroma of the chloroplast
B. Thylakoid membranes
C. Outer membrane of the chloroplast
D. Electron transport chain
E. Thylakoid space






Answer: A

Which of the following statements best represents the relationships between the light reactions and the Calvin cycle?

Which of the following statements best represents the relationships between the light reactions and the Calvin cycle?

A. The light reactions provide ATP and NADPH to the Calvin cycle, and the cycle returns ADP+P1, and NADP+ to the light reactions
B. The light reactions provide ATP and NADPH to the carbon fixation step of the Calvin cycle, and the cycle provides water and electrons to the light reaction
C. The light reactions supply the Calvin cycle with CO2 to produce sugars, and the Calvin cycle
D. The light reactions provide the Calvin cycle with oxygen for electron flow, and the Calvin cycle provides the light reactions with water to split
E. There is no relationship between the light reactions and the Calvin cycle

Answer: A

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

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

A. On the side facing the thylakoid space
B. On the ATP molecules themselves
C. On the pigment molecules of PSI and PSII
D. on the stroma side of the membrane
E. Built into the center of the thylakoid stack (granum)

Answer: D

Carotenoids are often found in foods that are considered to have antioxidant properties in human nutrition. What related function do they have in plants?

Carotenoids are often found in foods that are considered to have antioxidant properties in human nutrition. What related function do they have in plants?

A. They serve as accessory pigments
B. They dissipate excessive light energy
C. They cover the sensitive chromosomes of the plant
D. They reflect orange light
E. They take up toxins from the water





Answer: B

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

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

A. Using mutated organisms that can grow but that cannot carry out cyclic flow of electrons and compare their abilities to photosynthesis in different light intensifies
B. Using plants that can carry out both linear and cyclic electron flow, or only one or another of three processes, and measuring their light absorbable
C. Using bacteria that have only cyclic flow and look for their frequency of mutation damage
D. Using bacteria with only cyclic flow and measuring the number and the types of photosynthetic pigments they have in their membranes
E. Using plants with only photosystem I operative and measure how much damage occurs at different wavelengths

Answer: A

Some photosynthetic bacteria have photosystem I but not II, while others have both PSI and PSII. Which of the following might this observation imply?

Some photosynthetic bacteria have photosystem I but not II, while others have both PSI and PSII. Which of the following might this observation imply?

A. Photosystem II must have been selected against in some species
B. Photosystem I must be ancestral
C. Photosystem II may have evolved to be more photoprotective
D. Cyclic flow must be more primitive than linear flow electrons
E. cyclic flow must be the most necessary of the two processes





Answer: B

P680+ is said to be the strongest biological oxidizing agent. Why?

P680+ is said to be the strongest biological oxidizing agent. Why?

A. it is the receptor for the most excited electron in either photosystem
B. it is the molecule that transfers electrons to Pq of the electron transport chain
C. NADP reductase will then catalyze the shift of the electron from Fd to NADP+ to reduce it to NADPH
D. this molecule results from the transfer of an electron to the primary electron acceptor of photosystem II and strongly attracts another electron
E. this molecule is found far more frequently among bacteria as well as plants and plantlike protists

Answer: D

In a protein complex for the light reaction ( a reaction center), energy is transferred from pigment molecule to pigment molecule, to a special chlorophyll a molecule, and eventually to the primary electron acceptor. why does this occur?

In a protein complex for the light reaction ( a reaction center), energy is transferred from pigment molecule to pigment molecule, to a special chlorophyll a molecule, and eventually to the primary electron acceptor. why does this occur?

A. the action spectrum of that molecule is such that it is different from other molecules of chlorophyll
B. the potential energy of the electron has to go back to the ground state
C. the molecular environment lets it boost an electron to a higher energy level and also transfer the electron to another molecule
D. each pigment molecule has to be able to act interdependently to excite electrons
E. these chlorophyll a molecules are associated with higher concentrations of ATP






Answer: C

What is the relationship between wavelength of light and the quantity of energy per photon?

What is the relationship between wavelength of light and the quantity of energy per photon?

A. they have a direct, linear relationship
B. the are inversely related
C. they are logarithmically related
D. they are separate phenomena
E. they are only related in certain parts of the spectrum




Answer: B

Generation of photon gradients across membranes occurs during

Generation of photon gradients across membranes occurs during 

A. photosynthesis
B. respiration
C. both photosynthesis and respiration
D. neither photosynthesis nor respiration
E. photorespiration

Answer: C

The splitting of carbon dioxide to form oxygen gas and carbon compounds occurs during

The splitting of carbon dioxide to form oxygen gas and carbon compounds occurs during

A. photosynthesis
B. respiration
C. both photosynthesis and respiration
D. neither photosynthesis nor respiration
E. photoresiration





Answer: D

Reduction of NADP+ occurs during

Reduction of NADP+ occurs during

A. photosynthesis
B. respiration
C. both photosynthesis and respiration
D. neither photosynthesis nor respiration
E. photorespiration






Answer: A

Reduction of oxygen which forms water occurs during

Reduction of oxygen which forms water occurs during

A. photosynthesis
B. respiration
C. both photosynthesis and respiration
D. neither photosynthesis nor respiration
E. photorespiration






Answer: B

Synthesis of ATP by the chemiosmotic mechanism occurs during

Synthesis of ATP by the chemiosmotic mechanism occurs during

A. photosynthesis
B. respiration
C. both photosynthesis and respiration
D neither photosynthesis nor respiration
E. photorespiration

Answer: C

Where are the molecules of the ETC found in plant cells?

Where are the molecules of the ETC found in plant cells?

A. thylakoid membranes of chloroplasts
B. stroma of chloroplasts
c. inner membrane of mitochondria
D. matrix of mitochondria
E. cytoplasm




Answer: A

Which of the following statements best describes the relationship between photosynthesis and respiration?

Which of the following statements best describes the relationship between photosynthesis and respiration?

A. Respiration is the reversal of the biochemical pathways of photosynthesis
B. photosynthesis stores energy in complex organisms, while respiration releases it
C. photosynthesis occurs only in plants and respiration occurs only in animals
D. ATP molecules are produced in photosynthesis and used up in respiration
E. respiration is anabolic and photosynthesis is catabolic





Answer: B

In mitochondria, chemiosmosis translocates protons from the matrix into the intermembrane space, whereas in chloroplasts, chemiosmosis translocates protons from

In mitochondria, chemiosmosis translocates protons from the matrix into the intermembrane space, whereas in chloroplasts, chemiosmosis translocates protons from

A. the stroma to the photosystem II
B. the matrix to the stroma
C. the stroma to the thylakoid space
D. the intermembrane space to the matrix
E. ATP synthase to NADP+ reductase



Answer: C

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

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

A. thylakoid membrane
B. plasma membrane
C. inner mitochondrial membrane
D. A and C
E. A,B, and C







Answer: D

Suppose the interior of the thylakoids of isolated chloroplasts were made acidic and then transferred in the dark to a pH-8 solution. What would be likely to happen?

Suppose the interior of the thylakoids of isolated chloroplasts were made acidic and then transferred in the dark to a pH-8 solution. What would be likely to happen?

A. the isolated chloroplasts will make ATP
B. the calvin cycle will be activated
C. Cyclic photophosphorylation will occur
D. only A and B will occur
E. A,B, and C will occur






Answer: A

What does the chemiosmotic process in chloroplasts involve?

What does the chemiosmotic process in chloroplasts involve?

A. establishment of a proton gradient
B. diffusion of electrons through the thylakoid membrane
C. reduction of water to produce ATP energy
D. movement of water by osmosis into the thylakoid space from the stroma
E. formation of glucose, using carbon dioxide, NADPH, and ATP

Answer: A

Assume a thylakoid is somehow punctured so that the interior of the thylakoid is no longer separated form the stroma. This damage will have the most direct effect on which of the following processes?

Assume a thylakoid is somehow punctured so that the interior of the thylakoid is no longer separated form the stroma. This damage will have the most direct effect on which of the following processes?

A. the splitting of water
B. the absorption of light energy by chlorophyll
C. the flow of electrons from photosystem II to photosystem I
D. the synthesis of ATP
E. the reduction of NADP+






Answer: D

As a research scientist, you measure the amount of ATP and NADPH consumed by the Calvin cycle in 1 hour. You find 30,000 molecules of ATP consumed, but only 20,000 molecules of NADP. Where did the extra ATP molecules come from?

As a research scientist, you measure the amount of ATP and NADPH consumed by the Calvin cycle in 1 hour. You find 30,000 molecules of ATP consumed, but only 20,000 molecules of NADP. Where did the extra ATP molecules come from?

A. photosystem II
B. photosystem I
C. cyclic electron flow
D. linear electron flow
E. chlorophyll





Answer: C

What are the products of linear photophosphorylation?

What are the products of linear photophosphorylation?

A. heat and fluorescence
B. ATP and P700
C. ATP and NADPH
D. ADP and NADP
E. P700 and P680







Answer: C

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

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

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






Answer: B

Which of the following are directly associated with photosystem I?

Which of the following are directly associated with photosystem I?

A. harvesting of light energy by ATP
B. receiving electrons from plastocyanin
C. P680 reaction-center chlorophyll
D. extraction of hydrogen electrons from the splitting of water
E. passing electrons to plastoquinone





Answer: B

Which statement describes the functioning of photosystem II?

Which statement describes the functioning of photosystem II?

A. light energy excites electrons in the electron transport chain in a photosynthetic unit
B. the excitation is passed along a molecule of P700 chlorophyll in the photosynthetic unit
C. The P680 chlorophyll donates a pair of photons to NADPH. which is thus converted to NADP+
D. the electron vacancies in P680 are filled by electrons derived from water
E. the splitting of water yields molecular carbon dioxide as a by-product





Answer: D

Which of the events listen below occur in the light reactions of photosynthesis?

Which of the events listen below occur in the light reactions of photosynthesis?

A. NADP is produced
B. NADPH is reduced to NADP+
C. carbon dioxide is incorporated into PGA
D. ATP is phosphorylated to yeild ATP
E. light is absorbed and funneled to reaction-center chlorophyll a

Answer: E

The reaction-center chlorophyll of photosystem I is known as P700 because

The reaction-center chlorophyll of photosystem I is known as P700 because

A. there are 700 chlorophyll molecules in the center
B. this pigment is best at absorbing light with a wavelength of 700 nm
C. there are 700 photosystem I components to each chloroplast
D. it absorbs 700 photons per microsecond
E. the plastoquinone reflects light with a wavelength of 700 nm





Answer: B

In the thylakoid membranes, what is the main role of the antenna pigment molecules?

In the thylakoid membranes, what is the main role of the antenna pigment molecules?

A. split water and release oxygen to the reaction-center chlorophyll
B. harvest photons and transfer light energy to the reaction-center complex
C. synthesize ATP from ADP and P1
D. transfer electrons to ferredoxin and then NADPH
E. concentrate photons within the stroma








Answer: B

Compared with the lines for chlorophyll a in the figure, where would you expect to find the lines to differ for chlorophyll b?

Compared with the lines for chlorophyll a in the figure, where would you expect to find the lines to differ for chlorophyll b?

A. the absorption spectrum line would be the lowest for chlorophyll b somewhat to the right of that for chlorophyll a (500-600)
B. the rate of photosynthesis line for chlorophyll b would be lowest from 600-700 nm
C. the lines for the two types of chlorophyll would be almost completely opposite
D. the lines for the two types of chlorophyll would be almost completely identical
E. the peaks of the line for absorbance of b would be shifted to the left, and for the rate of photosynthesis would be shifted to the right.

Answer: A

What wavelength of light in the figure is most effective in driving photosynthesis?

What wavelength of light in the figure is most effective in driving photosynthesis?

A. 420 mm
B. 475 mm
C. 575 mm
D. 625 mm
E. 730 mm




Answer: A

What wavelength of light in the figure is most effective in driving photosynthesis?

What wavelength of light in the figure is most effective in driving photosynthesis?

A. 420 mm
B. 475 mm
C. 575 mm
D. 625 mm
E. 730 mm






Answer: A

Figure 10.1 shows the absorption spectrum for chlorophyll a and the action spectrum for photosynthesis. Why are they different?

Figure 10.1 shows the absorption spectrum for chlorophyll a and the action spectrum for photosynthesis. Why are they different?

a. green and yellow wavelengths inhibit the absorption of red and blue wavelengths
b. bright sunlight destroys photosynthetic pigments
c. oxygen given off during photosynthesis interferes with the absorption of light
d. other pigments absorb light in addition to chlorophyll a
e. aerobic bacteria take up oxygen which changes the measurement of the rate of photosynthesis

Answer: D

Theodor W. Engelmann illuminated a filament of algae with light that passed through a prism, thus exposing different segments of algae to different wavelengths of light. He added aerobic bacteria and then noted that the largest groups were found in the areas illuminated by the red and blue light. If you ran the same experiment without passing light through a prism, what would you predict?

Theodor W. Engelmann illuminated a filament of algae with light that passed through a prism, thus exposing different segments of algae to different wavelengths of light. He added aerobic bacteria and then noted that the largest groups were found in the areas illuminated by the red and blue light.
If you ran the same experiment without passing light through a prism, what would you predict?

a. there would be no difference in results
b. the bacteria would be relatively evenly distributed along the algal filaments
c. the number of bacteria present would decrease due to an increase in the carbon dioxide concentration
d. the number of bacteria present would increase due to an increase in the carbon dioxide concentration
e. the number of bacteria would decrease due to a decrease in the temperature of the water

Answer: B

Theodor W. Engelmann illuminated a filament of algae with light that passed through a prism, thus exposing different segments of algae to different wavelengths of light. He added aerobic bacteria and then noted that the largest groups were found in the areas illuminated by the red and blue light. An outcome of this experiment was to help determine

Theodor W. Engelmann illuminated a filament of algae with light that passed through a prism, thus exposing different segments of algae to different wavelengths of light. He added aerobic bacteria and then noted that the largest groups were found in the areas illuminated by the red and blue light.
An outcome of this experiment was to help determine

a. the relationship between heterotrophic and autotrophic organisms
b. the relationship between wavelengths of light and the rate of aerobic respiration
c. the relationship between wavelengths of light and the amount of heat released.
d. the relationship between wavelengths of light and the oxygen released during photosynthesis
e. the relationship between the concentration of carbon dioxide and the rate of photosynthesis

Answer: D

Theodor W. Engelmann illuminated a filament of algae with light that passed through a prism, thus exposing different segments of algae to different wavelengths of light. He added aerobic bacteria and then noted in which areas the bacteria congregated. He noted that the largest groups were found in the areas illuminated by the red and blue light. What did Engelmann conclude about the congregation of bacteria in the red and blue areas?

Theodor W. Engelmann illuminated a filament of algae with light that passed through a prism, thus exposing different segments of algae to different wavelengths of light. He added aerobic bacteria and then noted in which areas the bacteria congregated. He noted that the largest groups were found in the areas illuminated by the red and blue light.
What did Engelmann conclude about the congregation of bacteria in the red and blue areas?

a. bacteria released excess carbon dioxide in these areas
b. bacteria congregated in these areas due to an increase in the temperature of the red and blue light.
c. bacteria congregated in these areas because these areas had the most oxygen being released
d. bacteria are attracted to red and blue light thus these wavelengths are more reactive than other wavelengths
e. bacteria congregated in these areas due to an increase in the temperature caused by an increase in photosynthesis

Answer: C

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?

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?

a. red and yellow
b. blue and violet
c. green and yellow
d. blue, green, and red
e. green, blue, and yellow






Answer: B

When oxygen is released as a result of photosynthesis, it is a by-product of which of the following?

When oxygen is released as a result of photosynthesis, it is a by-product of which of the following?

a. reducing NADP+
b. splitting the water molecules
c. chemiosmosis
d. the electron transfer system of photosystem I
e. the electron transfer system of photosystem II






Answer: B

In autotrophic bacteria, where are the enzymes located that can carry on organic synthesis?

In autotrophic bacteria, where are the enzymes located that can carry on organic synthesis?

a. chloroplast membranes
b. nuclear membranes
c. free in the cytosol
d. along the outer edge of the nucleoid
e. along the inner surface of the plasma membrane







Answer: E

In any ecosystem, terrestrial or aquatic, what group(s) is (are) always necessary?

In any ecosystem, terrestrial or aquatic, what group(s) is (are) always necessary?

a. autotrophs and heterotrophs
b. producers and primary comsumers
c. photosynthesis
d. autotrophs
e. green plants





Answer: D

Where does the Calvin Cycle take place?

Where does the Calvin Cycle take place?

a. stroma of the chloroplast
b. thylakoid membrane
c. cytoplasm surrounding the chloroplast
d. chlorophyll molecule
e. outer membrane of the chloroplast





Answer: A

What are the products of the light reactions that are subsequently used by the Calvin Cycle?

What are the products of the light reactions that are subsequently used by the Calvin Cycle?

a. oxygen and carbon dioxide
b. carbon dioxide and RuBP
c. water and carbon
d. electrons and photons
e. ATP and NADPH





Answer: E

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

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

a. CO2 and glucose
b. H2O and O2
c. ADP, P1, and NADP+
d. electrons and H+
e. ATP and NADPH






Answer: E

If photosynthesizing green algae are provided with CO2 synthesized with heavy oxygen (^18O), later analysis will show that all but one of the following compounds produced by the algae contain the ^18O label. That one is

If photosynthesizing green algae are provided with CO2 synthesized with heavy oxygen (^18O), later analysis will show that all but one of the following compounds produced by the algae contain the ^18O label. That one is

a. PGA
b. PGAL
c. glucose
d. RuBP
e. O2

Answer: E