• I will be able to:
• Explain what photosynthesis is.
• Explain what happens during photosynthesis.
Photosynthesis
Cells and Heredity 2.1
P44-49
Objective: I will be able to explain How
Living Things Get Energy from the Sun.
• The Sun as an Energy Source.
– Nearly all living things obtain energy either
directly or indirectly from the energy captured
from the sun during photosynthesis.
Zebra- eat grass, it gets
energy that was stored in
the grass from the sun.
Lion- eats the zebra which
has stored energy from the
sun.
Objective: I will be able to explain How
Living Things Get Energy from the Sun.
• The Sun as an
Energy Source.
– Photosynthesis- the
process in which a
cell captures sunlight
and uses it to make
food.
• Photo- Greek for
“light”
• Syn “ putting
together”
Objective: I will be able to explain How
Living Things Get Energy from the Sun.
• The Sun as an Energy Source.
– Producers and Consumers
• Producers- Plants make their own food through
photosynthesis, called autotrophs.
• Consumers- heterotrophs- obtain food by eating
other organisms, or by absorbing their food
from other organisms (fungi)
Objective: I will be able to explain What
Happens During Photosynthesis.
• During Photosynthesis,
plants and some other
organisms absorb energy
from the sun and use
energy to convert carbon
dioxide and water into
sugars and oxygen.
– Stage 1: Capturing the Sun’s
Energy
– Stage 2 Using Energy to
Make Food
Objective: I will be able to explain What
Happens During Photosynthesis.
• Stage 1: Capturing the Sun’s Energy
– Energy is captured, mostly occurs in the leaves of
plants.
– Takes place in the chloroplast contains chlorophyll.
– Chlorophyll- green pigment made of colored chemical
compounds that absorb light.
Objective: I will be able to explain What
Happens During Photosynthesis.
• Stage 1: Capturing the
Sun’s Energy
– Functions as something
like solar cells, it captures
light energy and converts
it into a form that is used
in the second stage.
– Water in the chloroplasts
is split into hydrogen and
oxygen.
– Oxygen is given off as a
waste product.
Objective: I will be able to explain What
Happens During Photosynthesis.
• Stage 2 Using
Energy to Make
Food
– Cells produce sugars.
– Cells use the
hydrogen that came
from the water in
stage 1.
– Cells also use carbon
dioxide from the air
that passes through
openings in the leaf.
Objective: I will be able to explain What
Happens During Photosynthesis.
• Stage 2 Using Energy to Make Food
– Powered by the energy captured in stage
1, the H and CO2undergo a series of
reactions that results in the formation of
sugars. Glucose is a sugar written:
C6H12O6.
– Cells use the energy to carry out cell
functions.
– Waste product is oxygen- leaves through
openings in the leaf.
Objective: I will be able to explain What
Happens During Photosynthesis.
• Photosynthesis Equation (chemical)
– Light Energy + CO2 + H2O  C6H12O6 + O2
• Raw materials-CO2 + H2O
• Yields ( equals or produces) 
• Products- C6H12O6 + O2
• Energy is used in the reaction, therefore
it is written in on the left side.
Objective: I will be able to explain What
Happens During Photosynthesis.
• Photosynthesis Equation.
Objective: I will be able to explain What
Happens During Photosynthesis.
• Photosynthesis
Equation.
– Some are made into
other compoundscellulose for cell
walls (think active
transport)
– Stored in cells for
later use.
– When eating plants,
you are eating
stored energy.