1. Why Are Plants Important?
On the first day of our plant study, we mentioned things like crops, medicine, oxygen, food chains, shelter, and others. What one process allows plants to be this important?

2. PHOTOSYNTHESIS

3. Illuminating Photosynthesis Website:
A Big Picture Review…
What’s needed?
Energy + 12H2O + 6CO2 
Sunlight Water Carbon Dioxide
C6H12O O H2O
Glucose Oxygen Water
What’s produced?
Illuminating Photosynthesis Website:
We’ve looked at the left side of the equation, now let’s look at what happens to the products…

4. What happens to the water?
It evaporates out of the stomata in the leaves (helps “pull” water through the plant) and becomes a part of the atmosphere, or…
It is used to restart photosynthesis.

5. What happens to the glucose?
What is glucose?
Glucose is a monosaccharide.
The product of photosynthesis is always glucose, but glucose molecules can be combined to make other substances.
Ex. Starch in a potato
Glucose (or some form of glucose) is used by cells to complete respiration, the process that creates ATP for the body.

6. So, glucose can be…
Used by plant cells to complete respiration
(Glucose made in the leaves moves to all parts
of the plant through tubes called phloem)
Stored in a plant for later use.
Ex: potato, carrot, turnip…
Eaten by a heterotroph (animals, humans, etc.)
so they can complete respiration.

7. What happens to the oxygen?
The oxygen exits through stomata in the leaf.
What is the role of oxygen in the environment?

8. A different perspective on oxygen…
Does the oxygen we breath come only from plants?
More than half of Earth’s oxygen is produced by tiny phytoplankton in the ocean!
What is phytoplankton?
Plant-like protists and bacteria

9. Phytoplankton: plant-like organisms
Most phytoplankton are too small to see with the naked eye.
Phytoplankton live on the surface of the ocean where light is available for photosynthesis

10. Phytoplankton bloom in the South Atlantic (February 15, 2006) HI from space

12. The Photic Zone: the area of ocean that gets light
Sunlight does not reach deep water, its reach depends on how clear the water is
In coastal areas where there is sediment and living things in the water, the light does not reach as deep as 200 meters
The same is true for rivers, streams and ponds

13. The Role of Phytoplankton
Phytoplankton are the base of the marine food web
Phytoplankton tell us a lot about a marine ecosystem, including its health and availability of food

14. Marine Food Web Example

15. The Importance Of Phytoplankton
As we have just discussed, phytoplankton are an incredibly important part of life as we know it. They produce a huge amount of the oxygen we breathe, and they are the basis of the marine food chain.
Where are these phytoplankton blooms found in the ocean?
Scientists use satellite technology to see where chlorophyll is in the ocean. You can assume that the concentration of chlorophyll is a direct indicator of how many phytoplankton there are in an area. We will use these satellite images to investigate this topic further…