Hierarchy of management that covers different levels of management
Intro to Photosynthesis.pdf
1.
2. Map of Conceptual Change
1. True or False: Violet-blue and orange-red light work best for
photosynthesis.
2. CO2 enters and O2 exits the leaf by way of microscopic pores called
a. Stroma b. Stoma c. Thylakoid d. Chloroplast
3. True or false: Chlorophyll b absorbs blue-violet and red light.
4. What compound is the source of electrons for linear
electron flow?
a. NADP+ b. ATP c. Water d. Chlorophyll
5. True or False: Chemiosmosis drives ATP synthase to combine ADP and
phosphate group to form ATP.
Questions
After
Before
3.
4. Learning Competencies
• Describe how plants harness light energy from the
sun.
• Trace the flow of electrons through light reaction
events.
• Appreciate the importance of light reaction events in
the food making process of plants
5.
6. • Defined: process that
converts solar energy into
useful chemical energy that is
stored in sugar and other
organic molecules.
Photosynthesis
7. • Who: Autotrophs or self-
feeders (auto means “self”, and
trophos means “feeder”). They
produce their organic molecules
from CO2 and other inorganic
raw materials obtained from the
environment. They are the
ultimate sources of organic
compounds for all non-
autotrophic organisms, hence
they term as producers of the
biosphere.
1. Plants (photoautotrophs)
2. Algae (e.g. green algae,
kelps)
3. Other Eukaryotes (e.g.
phytoplankton)
4. Prokaryotes (e.g.
cyanobacteria)
8. Photosynthesis
• What: an endergonic
chemical reaction, a reaction
that requires energy to be
absorbed in order for it to
take place.
• Phases: Light-Dependent and
Light-independent.
• End result: Sugar (glucose)
and Oxygen
9. • A form of energy known as electromagnetic
energy, also called as electromagnetic
radiation.
• Travels in rhythmic waves caused by the
disturbances of electric and magnetic fields.
Consists of discrete particles called photons.
• The distance between the crests of
electromagnetic waves is called as
wavelength. It can range from less than
nanometer (Gamma rays) to more than
kilometer (Radio waves).
• The entire range of radiation is known as
electromagnetic spectrum.
Light
10. • The wavelength segment most
important to life is the visible
light.
• Visible light is observed as white
light, a mixture of color ROYGBIV.
• Colors are either reflected or
absorbed by objects.
• Most plants have green leaves,
which means they reflect green
light and absorb other colors.
• Violet-blue and orange-red light
work best for photosynthesis.
Light
11. Chloroplast
• Site of photosynthesis.
• Found mainly in the cells of
mesophyll, the tissue in the
interior of the leaf.
• CO2 enters and O2 exits the leaf
by way of microscopic pores
called stomata ( Greek word
stoma me aning “mouth”).
• Leaves use vein to transport
water and sugar.
• Has two membranes surrounding
a dense fluid called stroma.
12. Chloroplast
• Suspended within the stroma is a
third membrane system made up
of sacs called thylakoids.
Thylakoid sacs are stacked in
columns called grana (singular,
granum).
• Within the thylakoid membranes
of the chloroplast, the green
pigment that is essential in the
process of absorbing radiant
energy is called Chlorophyll.
13. Chloroplast
• Types of Chlorophyll:
Chlorophyll a – absorbs blue-violet
and red light; reflects green.
Chlorophyll b – absorbs blue and
orange light; reflects yellow-green.
Carotenoids – absorb blue-green
light; reflect yellow-orange.
Note: Chlorophyll b and
Carotenoids are examples of
accessory pigments that allow
plants to absorb more light
14. Phases
Phase 1: Light-Dependent Reaction
- Location: Thylakoid membranes
- Events: a. Chlorophyll Photoactivation
b. Photolysis
c. Photophosphorylation
- Creates: O2, ATP, NADPH
Phase 2: Light-Independent Reaction
- Location: Stroma
- Events: a. Carbon Fixation
b. Reduction
c. Regeneration
- Creates: Sucrose, ADP, NADP+, Inorganic phosphate.
15. Photosystems
• Composed of a reaction-center
complex surrounded by several
light-harvesting complexes.
• Found within the thylakoid
membrane together with the
chlorophyll molecules.
• Reaction-Center Complex is an
organized association of proteins
holding a special pair of chlorophyll
a and a primary electron acceptor.
16. Photosystems
• Light-Harvesting Complex consists
of various pigment molecules bound
to proteins (chlorophyll a, b and
carotenoids).
• Primary Electron Acceptor is a
molecule capable of accepting
excited electrons and becoming
reduced.
• Types: Photosystem I and
Photosystem II
• PS I was the first to discover but PS II
functions first in the light reactions.
17. Light-Dependent Reaction
• Also called as photochemical reaction.
• Event 1: Chlorophyll Photoactivation – is
the capture of light energy by
chlorophyll that results in the release of
energized electrons.
• Event 2: Photolysis – splitting of water
molecules into H- ions, electrons and
O2.
• Event 3: Photophosphorylation – is the
transfer of light energy absorbed by
chlorophyll to molecules of ATP.
18. • In eukaryotes that are autotrophs, photosynthesis occurs in chloroplasts,
organelles containing thylakoids. Stacks of thylakoids form grana.
• Photosynthesis is summarized as
6 CO2 + 12 H2O + Light energy S C6H12O6 + 6 O2 + 6 H2O.
• Light is a form of electromagnetic energy. The colors we see as visible light
include those wavelengths that drive photosynthesis. A pigment absorbs
light of specific wavelengths; chlorophyll a is the main photosynthetic
pigment in plants. Other accessory pigments absorb different wavelengths
of light and pass the energy on to chlorophyll a.
• A pigment goes from a ground state to an excited state when a photon of
light boosts one of the pigment’s electrons to a higher-energy orbital. This
excited state is unstable. Electrons from isolated pigments tend to fall back
to the ground state, giving off heat and/or light.
Concept Summary
J
20. • A photosystem is composed of a reaction-center complex surrounded by
light-harvesting complexes that funnel the energy of photons to the
eaction-center complex. When a special pair of reaction-center chlorophyll
a molecules absorbs energy, one of its electrons is boosted to a higher
energy level and transferred to the primary electron acceptor. Photosystem
II contains P680 chlorophyll a molecules in the reaction-center complex;
photosystem I contains P700 molecules.
• Linear electron flow during the light reactions uses both photosystems and
produces NADPH, ATP, and oxygen.
• During chemiosmosis in chloroplasts, electron transport chains generate an
H+ gradient across a membrane. ATP synthase uses this proton-motive force
to make ATP.
Concept Summary
J
22. Map of Conceptual Change
1. True or False: Violet-blue and orange-red light work best for
photosynthesis.
2. CO2 enters and O2 exits the leaf by way of microscopic pores called
a. Stroma b. Stoma c. Thylakoid d. Chloroplast
3. True or false: Chlorophyll b absorbs blue-violet and red light.
4. What compound is the source of electrons for linear
electron flow?
a. NADP+ b. ATP c. Water d. Chlorophyll
5. True or False: Chemiosmosis drives ATP synthase to combine ADP and
phosphate group to form ATP.
Questions
After
Before
