A presentation about photosynthesis

1. Unit 6 Lesson 1
Photosynthesis

2. Energy for Life
All organisms get their
energy from the sun!
How is this possible
though? Isn't this giraffe
getting its energy from
the tree he is eating?

3. The sun's energy cannot be used by cells without
some help.
Photosynthesis
Photosynthesis is the
process by which
plants make their own
food by turning water
and carbon dioxide
with the help of
sunlight into glucose
(sugar) and create the
waste product oxygen.

4. Plants Bacteria Algae
Many living things can perform
photosynthesis:
Photosynthesis

5. In addition to food, what do
plants provide to us which
we (and the fish in this
picture) need?
Chemicals involved in
Photosynthesis

6. Water: H2O
Carbon Dioxide: CO2
Oxygen: O2
Glucose: C6H12O6
Glucose is sugar, a complex carbohydrate containing
carbon. The individual molecules of Carbon,
Hydrogen and Oxygen are joined together to make
this molecule.
Chemicals involved in
Photosynthesis

7. Plant Cell Review
In an earlier chapter, we learned about cells and
organelles.
At your table, think back
and come up with a list of
some cell characteristics
and organelles which are
specific to plants alone.
Be ready to give an example to the class!

8. Chloroplasts
Why are chloroplasts essential?
At your table, think about it
for a minute.

9. Chloroplasts
Why are chloroplasts essential?
a. This is where
photosynthesis takes
place!
b. Chloroplasts make
chlorophyll - a pigment that
makes the leaf green and
traps the sunlight.

10. The pigment chlorophyll, which
makes leaves green and is
found inside the chloroplasts,
collects the energy of sunlight.
The roots collect water and the
stomata of the leaves collect
Carbon Dioxide (CO2). These
two materials - water and CO2
are called the reactants (raw
materials).
Reactants (Raw Materials) for
Photosynthesis
Photosynthesis occurs mainly in the leaves of plants and in the
chloroplasts.

11. The end result or product of
photosynthesis is glucose
(sugar) for the plant. This
also produces the waste
product oxygen (O2).
Glucose and Oxygen are
the products of
photosynthesis.
Products of
Photosynthesis

12. Stage 1: Collection of raw materials (sunlight energy,
water, carbon dioxide). Step 1 is called the light
“dependent” reactions.
Stage 2: Processing of the raw materials to form
glucose and oxygen. This step is called the Calvin
Cycle, which is also known as the light
“independent” or dark reactions.
Photosynthesis is a multi-
step process

13. The Calvin Cycle occurs when the molecules of carbon
dioxide and water are taken apart, rearranged and
recombined using the energy in sunlight to make
glucose and oxygen.
The Calvin Cycle
The Calvin Cycle is named for
Melvin Calvin, who in 1937
alongside his colleagues at
the University of California,
discovered the process.

14. Why is the Calvin
Cycle also called the
Dark Reaction?
It is not really dark!
It can happen anytime of
the day, but does not
require light to work.

15. ______ + _____ _______ + ______
Equation for Photosynthesis
Water
Carbon
Dioxide Glucose Oxygen

16. The process can be simplified into the following equation:
6CO2 + 6H2O C6H12O6 + 6O2
sunlight
The equation above contains 6 carbon molecules, 12
hydrogen molecules, and 18 molecules in both the
reactants and products. They have just been
regrouped into different compounds.
Equation for Photosynthesis

17. The process of Photosynthesis has stored the
energy of sunlight for later use! We get this
sunlight energy when we eat the plant or an
animal that ate the plant.
Overall Idea:
Photosynthesis
Glucose is used by the cell immediately or stored for
growth or later use. The oxygen is released as a
waste product, it leaves through the stomata.
This is good news because humans and many other
animals rely on this oxygen!

18. Big Ideas:
● Photosynthesis is the process by which plants make
their own food. - Takes place in the Chloroplast
● Reactants (Raw Materials):
○ Carbon Dioxide and Water along with energy from
the sun
● Products:
○ Glucose (sugar) and oxygen
● 2 Stages:
○ Stage 1 Light Dependent - when raw materials are
gathered by plant
○ Stage 2 Light Independent (Dark Reactions) -
Calvin Cycle - when plant turns raw materials into
glucose and oxygen
______ + _____ _______ + ______
Water
Carbon
Dioxide Glucose Oxygen