UNIT IV: PLANT GROWTH, DEVELOPMENT AND REPRODUCTION (PLANT LIFE PROCESSES) Flashcards
is the process through which green plants
convert solar energy to chemical energy in organic
molecules.
Photosynthesis
______generate their own organic matter through
photosynthesis
Autotrophs
Examples of Autotrophs organisms
(a) Mosses, ferns, and flowering plants
(b) Kelp
(c) Euglena
(d) Cyanobacteria
Makes organic molecules (glucose) out of inorganic materials (carbon dioxide and water).
Photosynthesis
It begins all food chains/webs. Thus all life is supported by this process. It also makes oxygen gas!!
Photosynthesis
____ absorb light energy and convert it to chemical energy
Chloroplast
•Absorbing Light Energy to make chemical
energy_____
Glucose
______is the process by which AUTOTROPHIC organisms use light energy to make sugar and oxygen gas from carbon dioxide and water
Photosynthesis
Photo-synthesis means ?
“putting together with light.”
Plants use_____ to turn water and carbon dioxide into_____. _____ is a kind of sugar.
sunlight
glucose
Glucose
Plants use_______ as food for energy and as a building block for growing
glucose
Sites of Photosynthesis
Chloroplasts
– All green plant parts have chloroplasts
and carry out photosynthesis
•The leaves have the most chloroplasts
•The green color comes from chlorophyll in
the chloroplasts
•The pigments absorb light energy
True
In most plants, photosynthesis occurs primarily in the leaves, in the chloroplasts
True
chloroplast contains?
•stroma, a fluid
•grana, stacks of thylakoids
_____is the green pigment that captures light for photosynthesis
Chlorophyll
What are the several pigments that Chloroplasts contain?
– Chlorophyll a
– Chlorophyll b
– Carotenoids
_____provides the energy and carbon needed to make other plant materials like wax and proteins.
Glucose
The______ makes sugar from carbon dioxide.
______generated by the light reactions provides the energy for sugar synthesis.
The ________ produced by the light reactions provides the electrons for the reduction of carbon dioxide to glucose
Calvin cycle
ATP (adenosine phosphate)
NADPH
What are the 2 phases of PHOTOSYNTHESIS ?
•Light Reactions or Photochemical Reactions or Light-dependent reaction
•Light-independent reaction or Dark Reactions or Biochemical Reactions
_____converts light energy into
chemical energy; produces ATP and
NADPH molecules to be used to fuel light-
independent reaction
•Light-dependent
_____uses ATP produced to
make simple sugars/ glucose
•Light-independent
•Requires light
•Occurs in chloroplast (in thylakoids)
•Chlorophyll (thylakoid) traps energy from
light
•Light excites electron (e-)
Light-dependent Reactions
•Energy lost along electron transport chain
•Lost energy used to recharge ATP from
ADP
•NADPH produced from e- transport chain
Light-dependent Reactions
What are the Total byproducts of Light-dependent Reactions?
ATP, NADPH, O2
What are the 3 components of light reactions ?
a. Photolysis of water (Hill Reaction)
b. Reduction of NADP+ to NADPH
c. Photophosphorylation
_____ water is split into hydrogen ions (H+),
electrons (e-) and molecular oxygen (O2).
2H2O + light— 4 H+ + 4e- + O2
Photolysis of water (Hill Reaction)
_____the electrons from water are transferred through photosynthetic electron transfer system to NADP+ to form NADPH.
2NADP+ + 2H+ + 4e- + light —2NADPH
Reduction of NADP+ to NADPH
- light and inorganic phosphate (Pi) are used to convert ADP to ATP.
ADP + Pi + light — ATP
Photophosphorylation
What are the 2 ways to make an ATP?
- Substrate level phosphorylation
- Electron transport chain (chemiosmosis)
_____ powers ATP synthesis in the light reactions
Chemiosmosis
•Does not require light
•Calvin Cycle
•Occurs in stroma of chloroplast
•Requires CO2
•Uses ATP and NADPH as fuel to run
•Makes glucose sugar from CO2 and
Hydrogen
Light-independent Reactions
•Carbon Fixation (light independent rxn).
•Occurs in the stroma.
•Uses ATP and NADPH from light reaction
(rxn).
•Uses CO2.
Calvin Cycle
To produce glucose: it takes 6 turns and uses 18 ATP and 12 NADPH.
True
The Calvin cycle has 3 phases
Fixation
Reduction
Regeneration
Called _____ because the CO2 is first incorporated
into a 3-carbon compound (3-PGA).
C3
•Stomata are open during the day
•Uses RUBISCO for the enzyme involved in the uptake of CO2.
•Photosynthesis takes place in the mesophyll cells
•Consists of the Calvin Cycle only
C3 Photosynthesis: C3 Plants
Most plants are C3 plants: such as ?
rice, legumes
Known as Hatch and Slack pathway (Hatch and
Slack, 1966).
C4 Photosynthesis: C4 Plants
Called ____ because the CO2 is first incorporated
into a 4-carbon compound (Oxaloacetate)
C4
•Uses PEP Carboxylase for the enzyme involved
in the uptake of CO2
•Stomata are open during the day
•Takes place in mesophyll cells and bundle-sheath cells
C4 Photosynthesis: C4 Plants
C4 plants include several thousand species.
Examples: ?
corn, sugarcane, sorghum
C4 plants have distinct bundle sheath called ?
“Kranz anatomy”
Called_____ after the family in w/c it was first
found (Crassulaceae) and because the CO2 is
stored in the form of an acid before use in
photosynthesis.
CAM Photosynthesis: CAM Plants (Crassulacean Acid Metabolism)
•Stomata are open at night and are usually closed
during the day,
•Photosynthesis takes place in the leaf mesophyll
•Uses PEP Carboxylase for the enzyme involved
in the uptake of CO2.
CAM Photosynthesis: CAM Plants
(Crassulacean Acid Metabolism)
What affects photosynthesis?
Light intensity
Carbon Dioxide
Temperature
