PHOTOSYNTHESISPHOTOSYNTHESIS

Engage Essential Question Explain

Engage

List 10 things that you used today that depend upon photosynthesis.

Think hard and record your list on your hand-out. This is an individual activity.

Possible answers Did you list items like the

plants that you ate? What about the clothing

that you are wearing? The bed or pillow that you

slept on? The fuel that heated your

water, your stove, microwave, vehicle?

What about…

Medicine

Oil

Coal

Essential Question

What materials does a seed need…

To develop into a tree?

Explore: van Helmont’s Willowexperiment of 1648

I have learned from this experiment that all Vegetables do immediately, and materially proceed out of the Element of water only. For I took an Earthen vessel, in which I put 200 pounds of Earth that had been dried in a Furnace, which I moistened with Rainwater, and I implanted therein the Trunk or Stem of a Willow Tree, weighing five pounds; and at length, five years being finished, the Tree sprung from thence, did weigh 169 pounds, and about three ounces: But I moistened the Earthen Vessel with Rain-water and it was large, and implanted into the Earth, and least the dust that flew about should be co-mingled with the Earth, I covered the lip or mouth of the Vessel with an Iron-Plate covered with Tin, and easily passable with many holes. I computed not the weight of the leaves that fell off in the four Autumns. At length, I again dried the Earth of the Vessel, and there were found the same two hundred pounds, wanting about two ounces. Therefore 164 pounds of Wood, Barks, and Roots, arose out of water only.

Explain

Take into account van Helmont’s results and revisit your previous list of materials that you believed a seed needs to develop into wood.

Consider whether van Helmont’s conclusion that only water is needed to produce plant biomass is justified. If not, why not.

PHOTOSYNTHESIS Photosynthesis is the ability of a plant to

turn sunlight, air, and water into sugar (energy).

The overall reaction is: light

chlorophyll

CO2 + H2O -------> C6H12O6 + O2

{Carbon dioxide} + {Water} yields {sugar} + {Oxygen}

Photosynthesis is vital to life for two reasons…

–1. The oxygen in the air comes from

photosynthesis. The plants continue to

replenish the oxygen in the air.

–2. All of our food comes directly or

indirectly from photosynthesis.

Where does

PhotosynthesisOccur?

Sunlight

Water

Carbon Dioxide

Oxygen

Glucose

#1 Light Dependent Reactions

ADP + P

NADP+

ATP

NADPH#2 Calvin Cycle

Photosynthesis Steps

ADP: Adenosine

Di-Phosphate

ATP: Adenosine

Tri-Phosphate

Where are chloroplasts located?

Chloroplast

Stomata

Light is captured by pigments- molecules that absorb specific wavelengths of light.

The main photosynthetic pigment is chlorophyll.

Chlorophyll absorbs most wavelengths of light except green. Green is what is reflected which is why this pigment appears green.

Trapping Energy from Sunlight

Light-dependent Reactions – convert light energy into chemical energy (Electron Transport Chain)

Light-independent Reactions – the molecules of ATP produced in light- dependent reactions produce the simple sugars (Calvin Cycle)

Intensity of lightIntensity of lightScarcity of water Scarcity of water Level of COLevel of CO22

What controls photosynthesisWhat controls photosynthesis?

Your Assignment

http://www.newtonsapple.tv/video.php?id=915

It is the year 2040 and you are a research scientist.The amount of sunlight that reaches the earth has been reduced because of some major event like pollution, volcanoes or global fires.Farmers are asking you for help to save their failing crops.Figure out ways that you might help.

Complete the chloroplast assignment before the next class.