1. Photosynthesis
Mr. Zito

2. General Formula

3. I. Energy
A. The sun is the source of energy for almost all life on earth.
1. Autotrophs -“Self Feeders”
a. Sun light and/ or inorganic compounds are used to produce organic compounds.

4. *phototrophic- plants, algae, and certain bacteria

5. *chemotrophic- bacteria in hostile environments
6CO2 + 6H2O + 3 H2S  C6H12O6 + 3H2SO4
Bacteria that thrive on the energy-rich chemical
compounds transported by hydrothermal fluids forming a food chain
that does not depend on the energy of the Sun or photosynthesis.

6. Instead of photosynthesis, vent ecosystems derive their energy from chemicals in a process called “chemosynthesis.” Both methods involve an energy source (1), carbon dioxide (2), and water to produce sugars (3). Photosynthesis gives off oxygen gas as a byproduct, while chemosynthesis produces sulfur (4)
Image courtesy Woods Hole Oceanographic Institution.Graphic from:

8. B. ATP- adenosine triphosphate
1. Structure
2.ATP is the “stored energy currency” of the cell- can be made available when needed.

17. II. Leaf Structure

18. Leaves are the primary photosynthetic organ of plants-large surface area for light to strike.
1. Cuticle- waxy layer on epidermis
a. protection
b. prevent water loss
2. Epidermis- single layer of flat cells.
a. used for protection

20. 3. Palisade Mesophyll- elongated cells
a. most chloroplast=most photosynthesis
4. Spongy Mesophyll-air pockets for gas exchange and circulation of water
a. fewer chloroplasts

22. 5. Vascular Bundle/Veins (xylem/phloem)
a. xylem: carries water and minerals upward to leaf cells from the stem and roots.
b. phloem: carries food made in the leaves to the stem and the roots for use and storage.

23. 6. Stomata/stomate- tiny openings that exchange gases and water with the atmosphere.
7. Guard Cell- one on each side of the stomata to regulate its opening and closing.
(open day/ closed night-
prevent water loss)

26. III. Chloroplast Structure

27. (inner- most membrane)
Thylakoids: Membrane “discs” arranged in stacks called grana.
(inner- most membrane)
1.Contain chlorophyll and other important molecules.
2. Site where solar energy is trapped and converted into chemical energy. (light- dependant reaction)

28. 1. Site of carbon fixation. (light- independent (dark) reactions)
B. Photosystems: clusters of proteins, chlorophyll, and other pigments in the thylakoid membrane.
C. Stroma: Thick enzyme-rich fluid filled area surrounding the thylakoid membrane.
1. Site of carbon fixation. (light- independent (dark) reactions)

30. IV. Light and Pigments
Light absorbing molecules- PIGMENTS.
Pigments absorb certain wavelengths and reflect others.
Chlorophyll- primary green pigment in photosynthesis.
Absorbs blue- violet and orange-red best. (BEST LIGHT)
Reflects green and yellow (WORST LIGHT)
Carotinoids- yellow and orange
pigments.