Summary of Photosynthesis

• By Anando Neethling

WHAT IS PHOTOSYNTHESIS?

The process that occurs in green plants, whereby solar energy is converted into chemical energy and stored as organic molecules by making use of carbon dioxide, sunlight, and water. Water and Oxygen are formed as byproducts.

Photosynthesis can be summarized in the following equation:

6 CO2 + 12 H2O + Light energy

C6H12O6 + 6 O2 + 6 H2O

(glucose)

WHO OR WHAT CAN PHOTOSYNTHESIZE? Photoautotrophs can

photosynthesize. Include: Green plants, algae,

cyanobacteria and green protists.Plants

Green protistsAlgae

WHY DO PLANTS PHOTOSYNTHESIZE? To provide nutrients and oxygen for

heterotrophs. Heterotrophs are dependent on

autotrophs, because they cannot produce there own food.

WHAT PART OF THE PLANT IS RESPONSIBLE FOR PHOTOSYNTHESIS? Photosynthesis occurs in the chloroplasts

of plant cells. The chloroplasts are mainly concentrated

in the mesophyll cells of leaves. Chloroplast contain chlorophyll – green

pigment that absorbs sunlight. Chlorophyll fill the space in the thylakoid

membrane.

CHLOROPLAST

MESOPHYLL CELL (PALLISADE AND

SPONGY)

1 µm

Thylakoidspace

Chloroplast

GranumIntermembranespace

Innermembrane

Outermembrane

Stroma

Thylakoid

The Importance of Photosynthesis Energy entering chloroplasts as sunlight gets stored as

chemical energy in organic compounds

Sugar made in the chloroplasts supplies chemical energy and carbon skeletons to synthesize the organic molecules of cells.

Plants store excess sugar as starch in structures such as roots, tubers, seeds, and fruits

In addition to food production, photosynthesis produces the O2 in our atmosphere