Photosynthesis

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In words…

Carbon Dioxide + Water + Light Energy

→ Glucose + Oxygen In simplest chemical terms…

CO2 + H20 → CH2O + O2

In more detailed chemical terms…

6 CO2 + 12 H2O → C6H12O6 + 6 O2 + 6 H2O

Photosynthesis

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Photosynthesis Light Reactions

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CELL ANATOMY Middle Lamella Between the cell walls, this is the "glue" that holds adjoining cells together.

The middle lamella is high in calcium; thus calcium deficiencies result in abnormal plant growth.

Cell Wall This is the rigid but porous "building block" of plant cells, and a characteristic that

distinguishes plants from animals. Cell walls are not living material, but without them, plants

would not be able to grow upward.

Nucleus The "brain" of the cell, this contains much of the genetic material and wields control

over many cell functions.

Cytoplasmic membrane This thin semi-permeable layer serves as a "skin", and controls

movement of materials in and out of cells. Through osmosis it maintains turgor pressure for

cell rigidity.

Vacuole This part of a cell gets larger as cells get older, and can occupy a considerable

volume of the cell. It is the "storage" site of not only carbohydrates for food, but also waste

products.

Chloroplast Composed of the stroma and grana, this is the site of "food production" via

photosynthesis, where carbohydrates are produced. A typical cell has about 400 chloroplasts.

Mitochondria The "energy" center for the plant, the mitochondria is the site of respiration, to

power cell activities. A typical cell has about 2000 mitochondria.

Cytoplasm The word means "cell material", this is the living liquid medium, the site for many

cell reactions, and contains all of the organelles.

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Leaf Anatomy

http://preuniversity.grkraj.org/html/3_PLANT_ANATOMY.htm

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• Type of plant, C3 vs. C4

• Light intensity

• Temperature

• Carbon dioxide concentration

• Leaf water potential

• Leaf carbohydrates

• Leaf area index

• Plant maturity

Factors that Influence

Photosynthesis

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Law of the Minimum

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http://www.soilcropandmore.info/crops/Corn/How-Corn-Grows/index.htm

Husks/Cobs

Grain

Leaf Sheaths Stalk

Leaves

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• If corn only utilizes 1% of the sunlight striking the

leaves, what is its ultimate yield potential?

Photosynthesis Efficiency

National Farm Machinery Show

February 2013 Louisville, KY

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The Washington Post