Deck 5: Photosynthesis

Question 1

Discrete packets of kinetic energy in light are called

A) photons.
B) protons.
C) lasers.
D) electrons.
E) grana.

Answer 1

A

Question 2

Photosynthesis is the only form of autotrophic energy transfers among organisms in Earth's habitats.

Answer 2

False

Question 3

The main organic product of photosynthesis is

A) sunlight.
B) oxygen.
C) glucose.
D) carbon dioxide.
E) chlorophyll.

Answer 3

C

Question 4

The reactant (reactants)of photosynthesis is (are)

A) sunlight.
B) oxygen.
C) chlorophyll.
D) water and carbon dioxide.
E) glucose.

Question 5

Which of these groups represents organisms that are heterotrophs?

A) microorganisms that harness solar energy, converting it to chemical energy
B) non-photosynthesizing bacteria, fungi, earthworms
C) all organisms that developed after photosynthesis
D) photosynthesizing bacteria, algae, ferns, pine trees

Question 6

Which of the following is not a net product or reactant of photosynthesis?

A) oxygen
B) water
C) carbon dioxide
D) glucose
E) ATP

Question 7

Which of these portions of the electromagnetic spectrum has highest energy?

A) green light, at 510 nm
B) yellow light, at 590 nm
C) orange light, at 640 nm
D) ultraviolet light, at 330 nm
E) blue-green light, at 450 nm

Question 8

The survival of most organisms is immediately threatened if they live at the site of a catastrophic forest fire,volcanic eruption or dust storm.These events,however can launch soot,ash or dust into different levels of the atmosphere,measurably lowering available sunlight at locations thousands of miles from the site.The _____ are most quickly and strongly impacted at these distances,with lack of growth and reproduction.

A) autotrophs, such as crops and woodlands
B) heterotrophs, such as humans and livestock
C) deep-sea thermal vent communities
D) All of these will be impacted with similar severity.

Question 9

The main byproduct molecule of photosynthesis that is released into the environment is

A) ATP.
B) oxygen.
C) chlorophyll.
D) glucose.
E) carbon dioxide.

Question 10

The reactions of photosynthesis may be summarized as:

A) 6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂
B) 6CO + 6H₂O → C₆H₁₂O₆ + 6H₂O
C) 12CO₂ + 6H₂O → C₁₂H₁₂O₆ + 6H₂O
D) 6CO + 6H₂O → C₆H₁₂O_­6 + 6O₂

Question 11

The organelle that carries out photosynthesis in plants is the

A) chlorophyll.
B) ribosome.
C) lysosome.
D) mitochondria.
E) chloroplast.

Question 12

The energy source for the process of photosynthesis is

A) oxygen.
B) sunlight.
C) carbon dioxide.
D) chlorophyll.
E) glucose.

Question 13

The three main energetic components of sunlight are

A) ultraviolet radiation, visible light, and infrared radiation.
B) visible light, radio waves, and ultraviolet radiation.
C) ultraviolet radiation, visible light, and x-rays.
D) gamma rays, visible light, and infrared radiation.
E) microwaves, visible light, and ultraviolet radiation.

Question 14

The primary pigment molecule needed for photosynthesis is

A) ATP.
B) chlorophyll a.
C) oxygen.
D) glucose.
E) carbon dioxide.

Question 15

Organisms that make their own organic compounds from inorganic substances are called

A) heterotrophs.
B) animals.
C) autotrophs.
D) animorphs.

Question 16

The proportion of oxygen in our atmosphere today

A) has increased to 20% since before photosynthesis.
B) has remained about the same since the first organisms developed.
C) has decreased to 10%, from higher levels before photosynthesis.
D) increased rapidly since the development of water-splitting photosynthesis and eukaryotes.
E) has increased to 20%, including rapid increase since water-splitting photosynthesis and eukaryotes.

Question 17

Which of these organisms can carry out photosynthesis?

A) algae
B) cyanobacteria
C) plants, algae, and cyanobacteria
D) plants
E) a coral

Question 18

Photosynthesis is

A) not an oxidation-reduction reaction.
B) an energy transfer process that produces glucose and oxygen.
C) a chemical process not dependent on chlorophyll.
D) None of the answer choices are correct.
E) a set of reactions that produces water and carbon dioxide.

Question 19

Organisms that consume preexisting organic molecules are called

A) animorphs.
B) heterotrophs.
C) plants.
D) autotrophs.
E) None of the answer choices are correct.

Question 20

Which organism depends on photosynthesis for its life?

A) All of the answer choices are correct.
B) a human
C) an oak tree
D) a coral
E) a sea slug

Question 21

Identify the incorrect pairing of photosynthetic carbon pathways and the type of habitat in which they live.

A) CAM pathway plants are found in desert habitats.
B) All of these correctly match the pathway and the habitat.
C) C₄ pathway plants are found in hot, open, grassy areas.
D) C₃ pathway plants are found in most habitat areas.

Question 22

In this cross-section of a typical plant leaf,the ______ are where photosynthesis takes place.

A) mesophyll cells
B) outer epidermis cells
C) air spaces
D) stomata

Question 23

Which plants keep their stomata open only at night?

A) C₄
B) C₃
C) CAM

Question 24

The Calvin cycle

A) is a linear pathway that passes high-energy electrons to glucose molecules.
B) is a cyclic reactive pathway that produces ATP and NADPH to drive other cell processes.
C) is a linear reactive pathway that produces three-carbon molecules from CO₂.
D) is a cyclic reactive pathway that produces three-carbon molecules from CO₂.

Question 25

As this graph shows,photosynthesizing eukaryotes have several pigments and accessory pigments that selectively capture the green wavelengths of photons for photosynthesis.

Question 26

The main organic molecule product of the carbon reactions is

A) NADPH.
B) a carbohydrate.
C) carbon dioxide.
D) ATP.
E) oxygen.

Question 27

Examples of accessory pigments for photosynthesis are

A) chlorophyll a and chlorophyll b.
B) mitochondria.
C) carotenoids, chlorophyll b, and chlorophyll a.
D) chlorophyll a and carotenoids.
E) chlorophyll b and carotenoids.

Question 28

In photosynthesis,the carbon in CO₂ is being _____ to form glucose.

A) reduced
B) broken down
C) oxidized
D) respired
E) energized

Question 29

In plant cells,a membrane studded with photosynthetic pigments in plant cells is the

A) thylakoid.
B) stroma.
C) chlorophyll.
D) chloroplast.
E) granum.

Question 30

Photosystem II produces

A) oxygen.
B) high-energy electrons.
C) both oxygen and high-energy electrons.
D) water.
E) NADPH.

Question 31

Figuer:
Examine this image, showing an electron transport chain in photosynthesis.
The electrons flowing through the electron transport chains in photosynthesis come from ____ and end up being carried by _____.

A) oxygen; NADPH
B) NADPH; water
C) NADPH; oxygen
D) oxygen; water
E) water; NADPH

Question 32

A gelatinous fluid inside the chloroplast containing ribosomes,DNA,and enzymes is the

A) thylakoid.
B) stroma.
C) chlorophyll.
D) granum.
E) mitochondrion.

Question 33

Accessory pigments include molecules that reflect reds,oranges and yellows.Leaves of many plants show these colors in the fall because

A) the cooler weather causes the plant to produce more of the accessory photosynthetic pigments.
B) the lessening of daylight as winter approaches causes the plant to produce more of the accessory photosynthetic pigments.
C) plants produce more chlorophyll.
D) the chlorophyll in the leaves degrades as winter approaches.
E) All of the answer choices are correct.

Question 34

In photosynthesis,the oxygen atoms in H₂O are initially

A) oxidized.
B) respired.
C) energized.
D) reduced.
E) broken down.

Question 35

Rubisco combines ribulose bisphosphate with carbon from

A) carbon dioxide.
B) carbon monoxide.
C) glucose.
D) organic compounds.
E) ATP.

Question 36

Tiny openings in the leaf epidermis that allow air exchange in and out of the leaf are

A) grana.
B) thylakoid spaces.
C) stomata.
D) thylakoids.
E) stroma.

Question 37

Photosystem I initiates the electron transport chain that produces

A) NADPH.
B) ATP.
C) NADH.
D) glucose.
E) water.

Question 38

Photosystem I and photosystem II are respectively part of

A) the carbon reactions only.
B) the light reactions and the carbon reactions.
C) the carbon reaction and the light reactions.
D) respiration.
E) the light reactions only.

Question 39

The energy sources needed for the light reactions and the carbon reactions respectively are

A) sunlight and ATP.
B) sunlight and carbon dioxide.
C) ATP and carbon dioxide.
D) Sunlight serves as the energy source for both sets of photosynthetic reactions.
E) ATP and sunlight.

Question 40

What is released at each step in an electron transport chain?

A) ultraviolet wavelengths
B) electrons
C) energy
D) photons

Question 41

If a thylakoid is placed in a basic solution ATP synthesis will occur.How is this possible?

A) An electron gradient is created by the difference in pH.
B) A proton gradient is created by the difference in pH.
C) ATP is formed spontaneously at low pH.
D) ATP cannot be broken down at low pH.
E) The carbon reactions are blocked in the thylakoid at high pH.

Question 42

The role of water in photosystem I is in contributing electrons,hydrogens,and oxygen.The resulting electrons in photosystem I

A) are used by the Rubisco enzyme to complete carbon fixation with RuBP and CO₂.
B) directly pass through ATP synthase enzymes to activate them in transforming ADP to ATP.
C) prevent chlorophylls from losing all electrons and breaking apart as they capture light energy.
D) are added to hydrogens so they can be transported across the thylakoid membranes more easily.

Question 43

Combustion is an inorganic chemical reaction,with the net result of burning a log being a reverse reaction from photosynthesis.What products would be formed in burning a log?

A) carbon dioxide and glucose
B) oxygen and carbon dioxide
C) oxygen and water
D) carbon dioxide and water
E) glucose and oxygen

Question 44

How do CAM plants minimize photorespiration?

A) Stomata are only opened at night, storing oxygen in malate. During the day the oxygen is released for photosynthesis.
B) The light reactions and carbon reactions occur in different cells, so carbon dioxide does not come into contact with rubisco.
C) The light reactions and carbon reactions occur in different cells, so oxygen does not come into contact with rubisco.
D) Stomata are only opened at night, storing carbon dioxide in malate. During the day the carbon dioxide is released for photosynthesis.

Question 45

A plant performing photosynthesis will produce ____ and consume _____.

A) oxygen; carbon dioxide
B) carbon dioxide; oxygen
C) water; carbon dioxide
D) oxygen; water
E) carbon dioxide; water

Question 46

Chloroplasts contain their own DNA,but the genes on these chromosomes only encode about 10% of the proteins required for photosynthesis.This is evidence for

A) competition.
B) photosynthesis.
C) predation.
D) parasitism.
E) endosymbiosis.

Question 47

Why is photorespiration more of a problem for a plant when their stomata are closed?

A) Oxygen cannot enter the leaf, blocking normal respiration, so the plants switch to photorespiration.
B) Oxygen, from water in photosystem I, can't leave the leaf, and competes with carbon dioxide for rubisco's active site.
C) Water is lost when the stomata are open, and is not available to accept electrons from Photosystem I.
D) Carbon dioxide levels increase from the light reactions, and compete with oxygen for rubisco's active site.

Question 48

If ozone layers in the atmosphere are depleted

A) less visible wavelength radiation will reach the Earth's surface, causing an increase in photosynthesis.
B) less infrared wavelength radiation will reach the Earth's surface, causing global warming.
C) more infrared wavelength radiation will reach the Earth's surface, causing more cases of skin cancer.
D) more ultraviolet wavelength radiation will reach the Earth's surface, causing more genetic damage to organisms.
E) less ultraviolet wavelength radiation will reach the Earth's surface, causing global cooling.

Question 49

When NADP⁺ _____ in the light cycle it is ______ forming NADPH.

A) accepts electrons; oxidized
B) accepts electrons; reduced
C) donates electrons; reduced
D) donates electrons; oxidized

Question 50

How do C₄ plants minimize photorespiration?

A) The light reactions and carbon reactions occur in different cells, so carbon dioxide does not come into contact with rubisco.
B) Stomata are only opened at night, storing oxygen in malate. During the day the oxygen is released for photosynthesis.
C) Stomata are only opened at night, storing carbon dioxide in malate. During the day the carbon dioxide is released for photosynthesis.
D) The light reactions and carbon reactions occur in different cells, so oxygen does not come into contact with rubisco.

Question 51

Blue light has ___ energy than red light and is ____ by a green leaf.

A) less; reflected
B) more; absorbed
C) less; absorbed
D) more; reflected

Question 52

The carbon atoms in cellulose found in a log originally came from _____ absorbed by the plant.

A) oxygen in the atmosphere,
B) carbon dioxide in the air,
C) nutrients in the soil,
D) glucose in the roots,
E) water in the soil,

Question 53

When a plant encounters hot,dry conditions of stress,the

A) stomata open, decreasing gas exchange.
B) stomata close, decreasing gas exchange.
C) stomata open, increasing gas exchange.
D) stomata close, increasing gas exchange.

Question 54

What will happen to the pH inside of a thylakoid that is exposed to light?

A) It will not change.
B) It will increase.
C) It will decrease.

Question 55

In the carbon reactions,carbon dioxide molecules are reduced by the addition of electrons carried from the light reaction by

A) NADP^+.
B) ATP.
C) NADPH.
D) water.
E) oxygen.

Question 56

When NADPH _____ in the carbon reactions it is ______ forming NADP⁺.

A) donates electrons; reduced
B) accepts electrons; reduced
C) accepts electrons; oxidized
D) donates electrons; oxidized

Question 57

The sea slug Elysia chlorotica is green because it contains

A) chlorophyll.
B) pigments that reflect red and blue light.
C) algal chromosomes.
D) enzymes that produce green light.
E) heme.

Question 58

The sea slug Elysia chlorotica absorbs chloroplasts from the alga Vaucheria litorea as it digests the cells.Thousands of structure and transport proteins involved in photosynthesis require thousands of genes in DNA.The algal chloroplast contains only 10% of the genes,while the algal nucleus contains the rest.Chloroplasts function inside the sea slug,allowing it to live on sunlight and carbon dioxide,suggesting that

A) photosynthesis can occur outside of a chloroplast organelle found in algae.
B) chloroplasts alone are sufficient for photosynthesis, whether in algal cells or sea slug cells.
C) regions of DNA containing necessary genes for photosynthesis must be present in sea slug cells to retain functioning chloroplasts.
D) some of the algal cells are not digested and are living symbiotically inside digestive tract of the sea slugs.
E) algal genes controlling photosynthesis can produce necessary proteins prior to cell digestion, retaining function of the chloroplast.

Question 59

Plants require a lot of water for hydration,metabolism,homeostasis,and photosynthesis.How is water used in photosynthesis?

A) to combine with NADP⁺ to form NADPH
B) as an electron donor in the photosystems
C) as a substrate for ATP synthase
D) as an electron acceptor in the electron transport chain
E) to combine with ADP forming ATP

Question 60

Before photosynthetic cells became abundant,_____ would not be widespread.

A) heterotrophs
B) cells using anaerobic respiration
C) cells using aerobic respiration
D) chemoautotrophs

Question 61

Most biologists would agree that the most important metabolic pathway of living organisms is photosynthesis.

Question 62

The primary photosynthetic pigment,chlorophyll a,reflects most orange light that reaches it.

Question 63

The rise of photosynthetic organisms increased the concentration of CO₂ in the atmosphere.

Question 64

The carbon reactions produce ATP and NADPH.

Question 65

What is a product of the electron transport chain started by photosystem II?

A) glucose
B) ADP
C) oxygen
D) water
E) NADPH

Question 66

How are algal chloroplasts able to perform photosynthesis in a sea slug?

A) Other animals like puffer fish contain the algal photosystem II gene psbO and perform photosynthesis.
B) The chloroplast chromosomes were missing the photosystem II gene psbO.
C) The chloroplasts can function without the photosystem II gene psbO.
D) The sea slug chromosomes contain the algal photosystem II gene psbO.
E) The chloroplasts can perform photosynthesis if removed from an algal cell.

Question 67

The light reactions use ATP as their energy source.

Question 68

When chlorophyll a absorbs light,electrons are "excited" and ejected from the chlorophyll a molecule.

Question 69

When researchers Rumpho and Manhart looked at the genomes of sea slugs and chloroplasts,what hypothesis were they testing?

A) that only photosystem II is necessary for photosynthesis
B) that some sea slug genes were present in chloroplast chromosomes
C) that the sea slugs have to continuously consume chloroplasts to replace the older ones
D) that chloroplasts can function without some proteins involved in photosynthesis
E) that some chloroplast genes were present in the sea slug chromosomes

Question 70

How did the scientists rule out that the chloroplasts could function outside of a host cell?

A) They shined light on the chloroplasts and looked for oxygen production.
B) They found the algal photosystem II psbO gene in the sea slug chromosomes.
C) They injected the chloroplasts into a heterotrophic bacteria and it could now perform photosynthesis.
D) The chloroplast chromosomes were missing photosystem II gene psbO.
E) They did not find the photosystem II psbO gene in the puffer fish chromosomes.

Question 71

C₄ plants and CAM plants fix carbon twice during the photosynthetic reactions.

Question 72

Grana,thylakoids,and chloroplasts are structures in cells that are important to the process of photosynthesis.

Question 73

For most lawn grasses to grow well in hot,dry weather,they must be watered so that their stomata will remain open for longer periods of time to let in O₂.

Question 74

The sea slug Elysia chlorotica is a(n)

A) heterotrophic plant.
B) heterotrophic animal.
C) heterotrophic protist.
D) autotrophic plant.
E) autotrophic protist.