Photosynthesis
Science 06-03-2013
Topic of today
• Topic: Photosynthesis
• Learning goals:
– After todays lesson you will be able to:
• Describe what is photosynthesis
• List the reaction formula for the process of
photosynthesis
• Explain in where in plants photosynthesis takes places
• Explain why and how plants can survive only from light,
air and water
Photosynthesis
• What was photosynthesis again?
Energy
• ... + ... 
... + ...
Photosynthesis
• What was photosynthesis again?
Sunlight Energy
• CO2 + H2O

Glucose + O2
Photosynthesis
• Take a look around you…
• Now answer the following question:
– What wouldn’t exist in this classroom if
photosynthesis wouldn’t exist?
Photoautotrophs
Photosynthesis - Carbon assimilation
• Most autotrophic organisms get
energy-rich electrons by using light
– Photo-autotrophic
– Carbon-assimilation = photosynthesis
• Plants and some bacteria contain
green pigments which enables
photosynthesis to take place
• In plant cells this photosynthetic
pigments can be found in the
chloroplasts
Location of photosynthesis
• Chloroplasts are found mainly in the cells of the
mesophyll, the tissue in the interior of the leaf.
• Carbon dioxide enters the leaf, and oxygen exits,
by way of microscopic pores called stomata
• Water absorbed by the roots is delivered to the
leaves in veins
• A chloroplast has an envelope of two membranes
surrounding a dense fluid called the stroma.
• Suspended within the stroma is a third
membrane system, made up of sacs called
thylakoids, which segregates the stroma from the
thylakoid space inside these sacs.
• Chlorophyll, the green pigment that gives leaves
their color, resides in the thylakoid membranes of
the chloroplast.
Breatharians
Experiment + Lab Report
• Elodea