Bio 162 Final Objectives Questions
and Correct Answers | Latest Update
| A+
Review the structure of the chloroplast and know where the light reaction and the Calvin
cycle take place.
Ans:Light reactions take place in the thylakoid membrane of the granum.
The Calvin cycle takes place in the stroma (cytoplasm of the chloroplast).
The light reaction of photosynthesis begins when pigments in the chloroplast absorb light
energy (photons). At the end of the light reaction, where is the energy derived from the
photons stored?
Ans:In NADPH and ATP which are then used in the Calvin cycle.
Summarize the reactions occurring in the three phases of the Calvin cycle.
Ans:Fixation: CO2 is added to RuBP to form 3-PGA.
Reduction: 3PGA is reduced to G3P with the help of NADPH, the G3P is then converted to
glucose.
Regeneration: left over G3P goes on to regenerate to RuBP.
,Where does the energy for the Calvin cycle come from?
Ans:NADPH and ATP form the light reactions
How does the current atmosphere differ from that in which photosynthesis evolved?
Ans:Photosynthesis evolved in an atmosphere with significantly less oxygen and a higher
concentration of CO2, but as photosynthesis occurred more and more, the atmospheric level
of oxygen increased. Now, the atmosphere has more oxygen than it did then.
How does the current Earth's atmosphere reduce the efficiency of rubisco?
Ans:Since there is more oxygen, rubisco acts on oxygen to break down RuBp.
In what two ways does photorespiration drain energy from the plant?
Ans:1. Uses ATP
2. Results in a net loss of CO2.
Describe the interior of a typical leaf. How do gasses move from the atmosphere to the
chloroplast?
Ans:A leaf is comprised of mesophyll cells and parenchyma cells. Gasses from the
atmosphere enter the air spaces in the leaf through stomata on the suface.
,What are the advantages and disadvantages to a plant of OPENING stomata?
Ans:Advantages: Allows CO2 in.
Disadvantages: Allows O2 in and results in water loss.
What are the advantages and disadvantages to a plant of CLOSING stomata?
Ans:Advantages: Reduces H2O loss
Disadvantages: No CO2 can come in.
Diagram all reactions of C4 and CAM photosynthesis shown in class. Pay particular attention
to steps in which energy is consumed or fixation occurs.
Ans:C4: Spatial separation of carbon fixation and Calvin Cycle.
CAM: Temporal separation of carbon fixation and Calvin Cycle.
In C4 and CAM plants rubisco always operates under conditions of elevated CO2. How is
this achieved in C4 or CAM plants?
Ans:The conditions of elevated CO2 result from the spacial or temporal separation of the
Calvin cycle and exposure to oxygen.
Predict the relative success of C3, C4 and CAM plant in a cool, wet environment and in a hot
dry environment.
, Ans:CAM plants are most successful in Hot climates and C3 plants are the most successful in
wet environments.
What happens to the sugar that is produced by photosynthesis?
Ans:The sugar produced from photosynthesis either goes into storage as starch, structural
support as cellulose, or used in respiration as glucose.
For plants and animals, distinguish between innate and acquired resistance (immunity). Give
an example of each type of resistance from both plants and animals.
Ans:Innate immunity in Plants: waxy cuticle.
Innate immunity in animals: Inflammation, fever, skin, mucous membranes.
Acquired Immunity in plants: Hypersensitive response and systemic acquired resistance.
Acquired Immunity in animals: Antibodies, Cytotoxic T cells, Cell mediated response.
What form of immunity (innate or acquired) do secondary metabolites fall under?
Ans:Innate
What is the advantage to the plant of producing secondary metabolites such as capsaicin,
peppermint oil, tannins, caffeine and opium?
Ans:To ward off predators or poison predators.
and Correct Answers | Latest Update
| A+
Review the structure of the chloroplast and know where the light reaction and the Calvin
cycle take place.
Ans:Light reactions take place in the thylakoid membrane of the granum.
The Calvin cycle takes place in the stroma (cytoplasm of the chloroplast).
The light reaction of photosynthesis begins when pigments in the chloroplast absorb light
energy (photons). At the end of the light reaction, where is the energy derived from the
photons stored?
Ans:In NADPH and ATP which are then used in the Calvin cycle.
Summarize the reactions occurring in the three phases of the Calvin cycle.
Ans:Fixation: CO2 is added to RuBP to form 3-PGA.
Reduction: 3PGA is reduced to G3P with the help of NADPH, the G3P is then converted to
glucose.
Regeneration: left over G3P goes on to regenerate to RuBP.
,Where does the energy for the Calvin cycle come from?
Ans:NADPH and ATP form the light reactions
How does the current atmosphere differ from that in which photosynthesis evolved?
Ans:Photosynthesis evolved in an atmosphere with significantly less oxygen and a higher
concentration of CO2, but as photosynthesis occurred more and more, the atmospheric level
of oxygen increased. Now, the atmosphere has more oxygen than it did then.
How does the current Earth's atmosphere reduce the efficiency of rubisco?
Ans:Since there is more oxygen, rubisco acts on oxygen to break down RuBp.
In what two ways does photorespiration drain energy from the plant?
Ans:1. Uses ATP
2. Results in a net loss of CO2.
Describe the interior of a typical leaf. How do gasses move from the atmosphere to the
chloroplast?
Ans:A leaf is comprised of mesophyll cells and parenchyma cells. Gasses from the
atmosphere enter the air spaces in the leaf through stomata on the suface.
,What are the advantages and disadvantages to a plant of OPENING stomata?
Ans:Advantages: Allows CO2 in.
Disadvantages: Allows O2 in and results in water loss.
What are the advantages and disadvantages to a plant of CLOSING stomata?
Ans:Advantages: Reduces H2O loss
Disadvantages: No CO2 can come in.
Diagram all reactions of C4 and CAM photosynthesis shown in class. Pay particular attention
to steps in which energy is consumed or fixation occurs.
Ans:C4: Spatial separation of carbon fixation and Calvin Cycle.
CAM: Temporal separation of carbon fixation and Calvin Cycle.
In C4 and CAM plants rubisco always operates under conditions of elevated CO2. How is
this achieved in C4 or CAM plants?
Ans:The conditions of elevated CO2 result from the spacial or temporal separation of the
Calvin cycle and exposure to oxygen.
Predict the relative success of C3, C4 and CAM plant in a cool, wet environment and in a hot
dry environment.
, Ans:CAM plants are most successful in Hot climates and C3 plants are the most successful in
wet environments.
What happens to the sugar that is produced by photosynthesis?
Ans:The sugar produced from photosynthesis either goes into storage as starch, structural
support as cellulose, or used in respiration as glucose.
For plants and animals, distinguish between innate and acquired resistance (immunity). Give
an example of each type of resistance from both plants and animals.
Ans:Innate immunity in Plants: waxy cuticle.
Innate immunity in animals: Inflammation, fever, skin, mucous membranes.
Acquired Immunity in plants: Hypersensitive response and systemic acquired resistance.
Acquired Immunity in animals: Antibodies, Cytotoxic T cells, Cell mediated response.
What form of immunity (innate or acquired) do secondary metabolites fall under?
Ans:Innate
What is the advantage to the plant of producing secondary metabolites such as capsaicin,
peppermint oil, tannins, caffeine and opium?
Ans:To ward off predators or poison predators.
