Chapter 6-Photosynthesis
compounds that absorb light
pigment
Plants gather the sun's energy with light absorbing molecules called what?
pigments
What are the two energy carriers in photosynthesis?
ATP NADPH
What is one of the main energy-storage compounds used by cells?
ATP and NADPH
Which of the following is a reactant in the Calvin Cycle? O2 CO2 H2O C6H12O6
B
alternative pathway where CO2 is fixed into a four carbon compound
C4 pathway
Stage of photosynthesis; organic compounds are formed
Calvin Cycle
Light reaction is to ATP as Calvin Cycle is to what?
G3P
Distinguish between thylakoid and grana
Inside the chloroplast there are stacks of interconnected membrane sacs called thylakoids. The thylakoids occur in stacks called grana
How would an increase in the CO2 levels affect photosynthesis?
It would stimulate the rate of photosynthesis until that rate level off.
Explain how the world would be different if C4 and CAM plants had not evolved.
Many dry regions would be devoid of plant life, since C3 plants would not be able to survive there.
What is the enzyme (protein) that is directly involved in the production of ATP?
NADPH
Oxygen is produced at what point during photosynthesis?
When water is split
most important pigments of photosynthesis
chlorophylls
In what organelle does photosynthesis take place?
chloroplast
process of converting light energy from the sun into chemical energy in the form of organic compounds
photosynthesis
Where in the chloroplast does stage 1 occur?
thylakoid
What organelle in the plant makes food?
chloroplast
In the overall equation for photosynthesis, six molecules of carbon dioxide result in six molecules of what?
oxygen
process that synthesizes ATP
chemiosmosis
What are openings in the underside of a leaf that allow air to enter?
stomata
Energy is required for a variety of life processes including... A. growth and reproduction B. movement C. transport of certain materials across cell membranes D. all of the above
D
What is the first step in photosynthesis?
absorption of light energy
What pigment traveled the shortest distance? (on a page in one of the reviews, oh well)
blue-green
system of membranes inside chloroplast
thylakoids
What is the role of chloroplasts in plant cells?
use light energy to make carbohydrates
What is the source o oxygen produced during photosynthesis?
water
What 3 things affect the rate of photosynthesis?
water temperature light intensity
Explain how the light reactions would be affected if there were no concentration gradient of protons across the thylakoid membrane.
Without a concentration gradient, there would be no tendency for protons to move from the thylakoid into the stroma. As a result, ATP would not be synthesized by ATP synthase
Organisms that make their own food are called?
autotrophs
stack of thylakoids
grana
other feeders; consumers
heterotrophs
small pores on underside of leaf
stomata
Which of the following is NOT produced in the light-dependent reactions of photosynthesis?
sugars
What are the products of photosynthesis?
sugars and oxygen
What product is produce from chemiosmosis? Where does chemiosmosis occur? What causes this process to occur?
ATP is produced. occurs at the ATP synthase molecule in the thylakoid membrane. The production of ATP occurs because a concentration buildup of H+ occurs across the thylakoid membrane.
Explain why both autotrophs and heterotrophs depend on photosynthesis to obtain the energy they need for life processes.
Autotrophs produce compounds during photosynthesis that they can later break down to form ATP. Heterotrophs must consume autotrophs or other heterotrophs to obtain the compounds that can be broken down to form ATP. ATP is needed by all cells to perform life processes.
In a typical plant, all of the following factors are necessary except what? A.Chlorophyll B. Light C. Oxygen D. Carbon Dioxide E. Water
C
water conservation pathway used by some plants to fix carbon
CAM pathway
What is one of the principle compounds that living things use to store energy in?
CO2
What is the stage 2 of photosynthesis in which CO2 is fixed into an organic compound?
Calvin Cycle
During photosynthesis, what is the series of reactions that create complex carbohydrates needed for energy and growth?
Calvin cycle
The light independent reaction s of photosynthesis are also known as what?
Calvin cycle
Describe the role of chlorophyll in the biochemical pathways of photosynthesis.
Chlorophylls are pigments that absorb light energy during photosynthesis. Chlorophyll b assists chlorophyll a in capturing light energy. Excited electrons that leave chlorophyll a travel along 2 electron transport chains. The energy of these excited electrons is then used to form ATP and NADPH
Distinguish between C3, C4, and CAM plants.
In C3 plants, CO2 continually enters the Calvin cycle and a three carbon compound is made. A C4 plant fixes CO2 into four carbon organic compounds in certain cells. After these compounds are transported to the other cells, they release CO2, which then enters the Calvin cycle. CAM plants fix CO2 at night.
What substance from the light dependent reactions of photosynthesis is a source of energy for the Calvin cycle?
NADPH
What are the substances produced when water molecules are broken down during the light reactions?
Oxygen and hydrogen proton
What step is in the beginning of photosynthesis?
Pigments in photosystem II absorb light
What would happen to photosynthesis if all of the three-carbon sugars produced in the Calvin Cycle were used to produce organic compounds?
The Calvin cycle would stop.
The molecule that precedes the electron transport chains of both photosystem II and photosystem I is an electron acceptor. What is the original molecule that is the electron donor for both these systems?
The original electron donor is water.
Plants and animals exchange materials through the process of photosynthesis and respiration. How are the 2 processes similar?
The products of photosynthesis are the reactants of respiration
The role of chlorophyll in photosynthesis is to what?
absorb light energy
C6H12O6 + 6H2O + 6O2 ---> 6CO2 +12H2O + 36 ATP represents the process of what?
aerobic respiration
self-feeders; producers
autotrophs
The energy from the sun is converted into chemical energy in the form of organic compounds in a series of linked chemical reactions called a what?
biochemical pathway
incorporation of CO2 into organic compounds
carbon fixation
accessory pigments; yellow, orange and brown
carotenoids
During photosynthesis, light energy absorbed by the plant is converted into what?
chemical energy
What is the pigment of photosynthesis?
chlorophyll
organelle of photosynthesis
chloroplast
Heterotrophs are organisms that what?
consume other organisms for energy
series of molecules in thylakoid membranes that electrons are passed along
e transport chain
The sun is considered the ultimate source of energy for life on earth. Why?
either photosynthetic organisms or organisms that have eaten them provide energy for all other organisms on earth.
How do the electrons function in creating a concentration gradient of H+?
electrons pump ions
What is the color of light that is least useful to a plant during photosynthesis?
green
Oak tree is to autotroph as human is to ....
heterotroph
Organisms that eat other things to get energy are called?
heterotrophs
Why is chlorophyll green?
it reflects green wavelengths of light
What is an equation that best summarizes the process of photosynthesis?
light water + carbon dioxide ---> sugars+oxygen
What is the first process int he light independent reactions of photosynthesis?
light absorption
The Calvin cycle is another name for what?
light independent reactions
What is the stage 1 of photosynthesis in which light energy is converted into chemical energy stored in ATP and NADPH?
light reactions
stage of photosynthesis; light energy converted into chemical energy; stored in ATP and NADPH
light reactions
If carbon dioxide is completely removed from a plant's environment, what would you expect to happen to the plant's production of high-energy sugars?
no sugars will be produced
What is the major atmospheric byproduct of photosynthesis?
oxygen
The process whereby plants capture energy and make complex molecules is known as what?
photosynthesis
cluster of pigment molecules and protein pigments are embedded in
photosystem
acceptor of e lost from chlorophyll a
primary e acceptor
The leaves of a plant appear green because chlorophyll does what?
reflects green light
Name the part of the chloroplast where the Calvin cycle takes place.
stroma
solution surrounding grana
stroma
Light-dependent reactions is to oxygen as Calvin Cycle is to
sugar
