bio 1108 exam 2 (herrick) | UPDATED Questions with 100%
Verified Answers
Q1: photosynthesis
A: biochemical process for building carbohydrates using energy from sunlight and carbon
dioxide taken from the air
Q2: what is the photosynthesis equation?
A: CO2 + H2O > C6H12O6 + CO2
Q3: reduction (in photosynthesis)
A: molecules acquires electrons and gains energy
Q4: oxidation
A: molecules loses electrons and releases energy
Q5: what is being reduced in the photosynthesis equation?
A: CO2 > C6H12O6
Q6: what is being oxidized in the photosynthesis equation?
A: H2O > O2
Q7: who is the electron donor?
A: water; oxygen is transformed as a by product
Q8: photosynthetic electron transport chain
A: series of reactions that links oxidation of water to reduction of carbon dioxide
Q9: where is the electron transport chain located?
A: the thylakoid membrane
,Q10: where does the light cycle occur?
A: the grana
Q11: calvin cycle
A: sugars are synthesized from CO2
Q12: calvin cycle requires:
A: two molecules of NADH and three molecules of ATP for each CO2 incorporated into
carbohydrates
Q13: steps of the Calvin cycle
A: 1. carboxylation
2. reduction
3. regeneration
Q14: carboxylation
A: CO2 +(rubisco)+ RuBP = 2(3PGA)
the addition of CO2 to the 5carbon compound RuBP
Q15: rubisco
A: catalyzes carboxylation reaction which originally would take a long time
Q16: reduction (in Calvin cycle)
A: 3PGA(ATP and NAPH)> triode phosphate
NADPH transfers two electrons and one proton; inorganic phosphate is released
Q17: regeneration
A: triose phosphate (ATP)> RuBP > beginning of cycle
(regeneration of RuBP) a multistep process where 3carbon compounds are
reorganized and combined to produce RuBP
Q18: light reaction
A: water is broken apart in the chlorophyll molecule into H+ and OH ions in the presence of
light, resulting in the formation of NADPH and ATP
,Q19: photosystems
A: PSI and PSII; proteinpigmented complexes; the functional and structural unit that
absorbs light energy and uses it to drive electron transport
Q20: chlorophyll light absorption
A: zscheme; absorption of visible light by an antenna chlorophyll results in the transfer of
energy to an electron in a neighboring chlorophyll molecule
Q21: reaction center
A: configured pair of chlorophyll molecules where energy is transfered to, then converted
to chemical energy (from antennae chlorophyll)
Q22: PSII
A: energizes electrons to the beginning go the electron transport chain; when it loses an
electron, it is able to pull electrons from water
Q23: PSI
A: energizes electrons with a second input of light energy so that they can be used to
reduce NADP+
Q24: cytochromeb6f complex
A: where electrons pass between photosystems
Q25: cyclic electron transport
A: electrons from PSI are redirected from ferredoxin back into the electron transport chain
Q26: two major challenges
A: 1. if more light energy is absorbed than the Calvin cycle can use, excess energy can
damage the cell
solution: xanthophylls and antioxidants reduce the amount of reactive oxygen species
by converting excess energy to heat
2. rubisco can use both CO2 and O2 as substrates
photorespiration (where ATP is consumed)
Q27: leaf anatomy: epidermis
A: sheets of cells that line the leaf's upper and lower surfaces
, Q28: leaf anatomy: mesophyll
A: loosely packed photosynthetic cells
Q29: leaf anatomy: veins
A: vascular conduit unit that connects leaf to rest of the plant
Q30: function of leaf
A: allows gas exchange, photosynthesis and transpiration
Q31: why does CO2 uptake result in water loss?
A: when stomata open, water vapor escapes (water vapor molecules diffuse into areas of
lower concentration)
Q32: transpiration
A: loss of water vapor from leaves
Q33: stomata
A: pores in epidermis that allows CO2 to diffuse
into the leaf; consists of two guard cells surrounding a central pore; guard cells can
shrink or swell controlling opening
Q34: CAM plants (photosynthesis adaptation)
A: CAM photosynthesis; use nocturnal CO2 storage to avoid water loss during the day for
plants who live in arid climates
Q35: C4 plants (photosynthesis adaptation)
A: suppress photorespiration by increasing the concentration of CO2 in the immediate
vicinity of rubisco
do this by initially capturing CO2 in mesophyll cells by means of PEP carboxylase which
produces a 4carbon organic acid that diffuse through plasmodesmsts into bundle
sheaths
once inside, 4carbon compounds are decarboxylated, releasing CO2
cycle is completed as a 3carbon molecule diffuses back into mesophyll cells
operates faster than calvin cycle
includes: pineapple, corn, sugarcane, wheat
Verified Answers
Q1: photosynthesis
A: biochemical process for building carbohydrates using energy from sunlight and carbon
dioxide taken from the air
Q2: what is the photosynthesis equation?
A: CO2 + H2O > C6H12O6 + CO2
Q3: reduction (in photosynthesis)
A: molecules acquires electrons and gains energy
Q4: oxidation
A: molecules loses electrons and releases energy
Q5: what is being reduced in the photosynthesis equation?
A: CO2 > C6H12O6
Q6: what is being oxidized in the photosynthesis equation?
A: H2O > O2
Q7: who is the electron donor?
A: water; oxygen is transformed as a by product
Q8: photosynthetic electron transport chain
A: series of reactions that links oxidation of water to reduction of carbon dioxide
Q9: where is the electron transport chain located?
A: the thylakoid membrane
,Q10: where does the light cycle occur?
A: the grana
Q11: calvin cycle
A: sugars are synthesized from CO2
Q12: calvin cycle requires:
A: two molecules of NADH and three molecules of ATP for each CO2 incorporated into
carbohydrates
Q13: steps of the Calvin cycle
A: 1. carboxylation
2. reduction
3. regeneration
Q14: carboxylation
A: CO2 +(rubisco)+ RuBP = 2(3PGA)
the addition of CO2 to the 5carbon compound RuBP
Q15: rubisco
A: catalyzes carboxylation reaction which originally would take a long time
Q16: reduction (in Calvin cycle)
A: 3PGA(ATP and NAPH)> triode phosphate
NADPH transfers two electrons and one proton; inorganic phosphate is released
Q17: regeneration
A: triose phosphate (ATP)> RuBP > beginning of cycle
(regeneration of RuBP) a multistep process where 3carbon compounds are
reorganized and combined to produce RuBP
Q18: light reaction
A: water is broken apart in the chlorophyll molecule into H+ and OH ions in the presence of
light, resulting in the formation of NADPH and ATP
,Q19: photosystems
A: PSI and PSII; proteinpigmented complexes; the functional and structural unit that
absorbs light energy and uses it to drive electron transport
Q20: chlorophyll light absorption
A: zscheme; absorption of visible light by an antenna chlorophyll results in the transfer of
energy to an electron in a neighboring chlorophyll molecule
Q21: reaction center
A: configured pair of chlorophyll molecules where energy is transfered to, then converted
to chemical energy (from antennae chlorophyll)
Q22: PSII
A: energizes electrons to the beginning go the electron transport chain; when it loses an
electron, it is able to pull electrons from water
Q23: PSI
A: energizes electrons with a second input of light energy so that they can be used to
reduce NADP+
Q24: cytochromeb6f complex
A: where electrons pass between photosystems
Q25: cyclic electron transport
A: electrons from PSI are redirected from ferredoxin back into the electron transport chain
Q26: two major challenges
A: 1. if more light energy is absorbed than the Calvin cycle can use, excess energy can
damage the cell
solution: xanthophylls and antioxidants reduce the amount of reactive oxygen species
by converting excess energy to heat
2. rubisco can use both CO2 and O2 as substrates
photorespiration (where ATP is consumed)
Q27: leaf anatomy: epidermis
A: sheets of cells that line the leaf's upper and lower surfaces
, Q28: leaf anatomy: mesophyll
A: loosely packed photosynthetic cells
Q29: leaf anatomy: veins
A: vascular conduit unit that connects leaf to rest of the plant
Q30: function of leaf
A: allows gas exchange, photosynthesis and transpiration
Q31: why does CO2 uptake result in water loss?
A: when stomata open, water vapor escapes (water vapor molecules diffuse into areas of
lower concentration)
Q32: transpiration
A: loss of water vapor from leaves
Q33: stomata
A: pores in epidermis that allows CO2 to diffuse
into the leaf; consists of two guard cells surrounding a central pore; guard cells can
shrink or swell controlling opening
Q34: CAM plants (photosynthesis adaptation)
A: CAM photosynthesis; use nocturnal CO2 storage to avoid water loss during the day for
plants who live in arid climates
Q35: C4 plants (photosynthesis adaptation)
A: suppress photorespiration by increasing the concentration of CO2 in the immediate
vicinity of rubisco
do this by initially capturing CO2 in mesophyll cells by means of PEP carboxylase which
produces a 4carbon organic acid that diffuse through plasmodesmsts into bundle
sheaths
once inside, 4carbon compounds are decarboxylated, releasing CO2
cycle is completed as a 3carbon molecule diffuses back into mesophyll cells
operates faster than calvin cycle
includes: pineapple, corn, sugarcane, wheat
