Carbon: Transformations in Matter and Energy
Environmental Literacy Project
Michigan State University
Plants Unit
Activity 4.4 Explaining How Plants
Make Food: Photosynthesis
1
Plants make their own food
Materials
for growth:
Biosynthesis
Food
To Cells
Energy:
Cellular
respiration
2
Constructing explanations
Consider the
following as you
construct your
explanation:
• Evidence from
the investigation
• What you
learned from the
molecular
modeling activity
• Three Questions
Handout
3
Comparing Ideas with a Partner
• Compare your explanations for each of the
Three Questions.
– How are they alike?
– How are they different?
• Check your explanation with the middle- and
right-hand columns of the Three Questions
handout.
• Consider making revisions to your explanation
based on your conversation with your partner.
4
The Matter Movement Question
Where are atoms moving
from?
Where are atoms moving to?
5
Which atoms and molecules move so
that plants can do photosynthesis?
water
carbon dioxide
oxygen
glucose
6
How do glucose water, carbon dioxide, and oxygen
move for a plant leaf to photosynthesize?
water
carbon dioxide
oxygen
glucose
7
Matter Movement
CO2
Do you have:
• an arrow
showing carbon
dioxide or CO2
going into the
plant’s leaf cell?
8
Matter Movement
CO2
H2
O
Do you have:
• an arrow
showing water
or H2O going
into the plant’s
leaf cell?
9
Matter Movement
CO2
H2
O
Glucose
Do you have:
• an arrow
showing
glucose or
C6H12O6 leaving
the plant’s leaf
cell?
10
Matter Movement
CO2
H2
O
O2
Glucose
Do you have:
• an arrow
showing oxygen
or O2 leaving
the plant’s leaf
cell?
11
The Matter Change Question
How are atoms in molecules being rearranged into different
molecules inside a potato cell during photosynthesis?
12
Plants make glucose from
carbon dioxide and water in their leaves.
13
What happens inside the leaf cell
as it photosynthesizes?
Chemical
change
14
Matter Change
What is the name of the chemical change that
allows cells to make food?
Photosynthesis
Write the chemical equation for this change:
6 CO2 + 6 H2O C6H12O6 + 6 O2
15
Matter Change
What molecules are
carbon atoms in before
the chemical change?
Carbon dioxide or CO2
What molecules are
carbon atoms in after the
chemical change?
Glucose or C6H1206
Chemical
Change
What other molecules
are needed?
Water or H2O
What other molecules are
produced?
Oxygen or O2
16
Energy Change
What forms of energy go
into this chemical
change?
Light energy
What forms of energy
come out of this chemical
change?
Chemical energy
17
Matter Movement
What happens to
glucose made by
photosynthesis?
Glucose moves from
a plant’s leaves to all
of its cells.
18
Drawing arrows to show
matter movement for
photosynthesis
• Blue arrows: Carbon dioxide
enters the plant’s leaves from
the air (along with water from
the soil through the plant’s roots
and stem
• Green arrows: Sugar moves from
leaves to all plant cells
19
Telling the Whole Story
Question: How does a cell in the potato plant
get food to a cell in its root?
Matter movement: Carbon dioxide and water enter into the cell.
Matter change: Carbon dioxide and water react resulting in glucose and oxygen.
Energy change: The light energy of the sun is converted into chemical energy
that is stored in the high energy C-C and C-H bonds of glucose.
Matter movement: Glucose and oxygen leave the cell. The glucose is transported
to other cells in the plant, including root cells.
20
Exit Ticket
• 4.4 ET, available in canvas now
• Download, edot, and return the 4.4 Explainer
Tool about how Plants get energy to move and
function
21