Download Adenosine Triphosphate (ATP)

Photosynthesis
Standard
1f –Usable energy is captured from sunlight by
chloroplasts and is stored through the synthesis
of sugar (glucose) from carbon dioxide
1i – In the mitochondria and chloroplasts energy
from electrons is stored for ATP production
(Chemiosmosis)
– complex process by which visible sunlight is
converted into chemical energy in carbohydrate
molecules
Reactants
Products
light
6CO2 + 6H2O ▬► C6H12O6 + 6O2
– light-absorbing molecules
– green pigment
(plants reflect green
light and look green)
Chloroplast
-the organelle that
captures energy
from sunlight for
photosynthesis
• thylakoids – saclike photosynthetic
membranes
• grana – thylakoid stacks
• photosystems – light-collecting units
• stroma – region outside the thylakoid
membranes
Photosystems
II & I
(light-dependent
reactions)
O2

H2O
• produce oxygen gas
• occurs in the thylakoid membranes
- light-independent rxn.,
occurs in the stroma,
produces sugars
Photosynthesis
5 Essential Questions
1. Write the equation for photosynthesis.
2. In photosynthesis, light energy is converted into
___________ energy. This is called
___________________.
3. In what organelle does photosynthesis occur?
4. On what part of the chloroplast does the light
dependant reaction take place? What are the four
products of the reaction?
5. What is another name for the light independent
reaction? Where in the chloroplast does is take place?
What does it produce?
Adenosine Triphosphate (ATP)
- one of the main chemical compounds cells use
to store and release energy
- adenine
- 5-carbon sugar
- three phosphate groups
- light-independent rxn., occurs in the stroma,
produces sugars
CO2 + ATP + NADPH
phosphoglyceraldehyde (PGAL)
high-energy sugars (glucose), sometimes lipids and
amino acids
Photosystems
II & I
O2
(light-dependent
reactions)

ADP
NADP +
ATP
NADPH
• produce oxygen gas
• convert ADP and NADP+ into the energy carriers
ATP and NADPH
• occurs in the thylakoid membranes
ATP
Used to power:
1. active transport (Na+ K+ pump)
2. protein synthesis
3. muscle contractions
(nicotinamide adenine
dinucleotide phosphate)
electron
• high energy electron carrier
• NADP+ + 2e- = NADPH (electron
transport)
• pigment absorbs
light, electrons’
energy increases
and pass down the
electron transport chain
• H20 is oxidized to
replace the 2e-,
releasing O2 & H+
• uses energy from electrons to move more H+
inside
• uses energy from light to
reenergize the electrons
• NADP + electrons + H+ ions = NADPH (outside
the membrane)
• more H+ pumped into membrane creating a
chemiosmotic gradient
• H+ pass through ATP synthase producing ATP
• CHEMIOSMOSIS – coupling energy from the
electrons to create a gradient and make ATP