Name________________________________________ PD_________________ Date_________
Mr. Orend Honors Biology
Photosynthesis Study Guide
VOCABULARY:
Activation energy (EA)
Autotroph (aka producer)
Central vacuole
Enzymes
Oxygen
Surface area
ATP vs. ADP
Calvin Cycle
Chlorophyll vs. Chloroplast
Glucose (C6H12O6)
ROYGBIV
Thylakoids
ATP Synthase*
Carbon dioxide
Endergonic & Exergonic rxns*
Light reactions
Rubisco*
Trophic levels
*these are the ‘bonus’ challenge terms
REQUIREMENTS:
OVERVIEW AND ANATOMY:
1. Plants, algae, and photosynthetic bacteria are called ______________________ because they
can produce their own organic food. This food not only feeds the producer, but also the
other ___________________ levels of the food web.
2. During photosynthesis, plants use ___________ from the sun to convert __________ from
the air and ___________ from the soil into the high-energy food molecule _____________.
3. Carbon dioxide enters the plant through pores found on the bottom of
__________________. Water enters the plant through the __________________, an organ
system that is found underground. Both of these organs are spread out and feathery, which
maximizes their ______________________ ___________________ for absorption.
4. If you zoom into a plant tissue under the microscope, you can tell that it is made of
_______________________ cells because they all have special organelles, a nucleus to
store DNA, and the tissue is multicellular. You would also see that water is stored in the
_______________ __________________ of each cell. This supplies water for
photosynthesis but also helps to hold plants up against __________________.
5. Inside that same leaf cell, there are also lots of oval-shaped organelles called
_______________________. They are green because they possess two shades of the
pigment ________________________. In the fall, the green pigment starts to
_______________________, which allows yellow, orange, and red pigments show through.
“PHOTO-“ = light reactions “-SYNTHESIS” = Calvin Cycle
Carefully study figure 7-3 below to review the two specific phases of photosynthesis:
*the light reactions
*the Calvin Cycle
SPECIFIC PROCESS:
6. During the ________________ _______________________ of photosynthesis, photons of
light strike chlorophyll molecules. This energy is strong enough to split molecules of
_______________ apart! The oxygen byproduct escapes the cell and ultimately the leaf.
However, the hydrogens build up inside the tight space of the ______________________,
which creates a lot of pressure. When the pressure is too great, the atoms start to escape
through a turning enzyme ‘mill’ called _____________ ______________________. This
enzyme starts to spin quickly, which charges up the cell’s ________________ ‘batteries’.
7. The sugar synthesis phase, which is also called the _____________________
_______________________, happens in the liquid ___________________ of the
chloroplast. It starts when the enzyme ______________________ grabs on to three
molecules of ___________________ _____________________. This starts a chain
reaction of bond breaking and reforming. The molecules get passed from
___________________ to enzyme, one of which adds the hydrogen atoms that were
gathered in the previous light reactions. After several enzyme-controlled steps, powered by
the energy molecule ________________, a sugar called _____________________ pops out!
8. Now that the glucose (or fat or proteins) molecules are present, they can be stored in the
plant or algae for later, or they might be eaten by a _______________________ as a food
source.
REVIEW:
Identify the stage of photosynthesis in which the following things happen:
(Light Reactions or Calvin Cycle)
A) Glucose is produced
_________________________
B) CO2 enters the chloroplast
_________________________
C) Water molecules split
_________________________
D) ATP ‘batteries’ are charged up
_________________________
E) Sun energy is absorbed by chlorophyll
_________________________
F) Hydrogens are bonded to carbons
_________________________
G) Oxygen leaves the leaf through the stomata
_________________________
H) Hydrogens build up inside the thylakoids
_________________________
I) ATP Synthase starts to spin
_________________________
J) Enzymes utilize ATP energy to build bonds
_________________________