A power point presentation on-PHOTOSYN

THESIS

#Contents• What is Photosynthesis?• Conditions necessary for it…• Role of stomata in the

process…• How plant get Co2 and

water…• Site of photosynthesis-

chloroplasts• Events occur during the

process…• How it occur in desert plants• Some other materials used

during the process…• Group members

What is Photosynthesis???

The process by which green plants make their own foods, is

called photosynthesis.Oxygen gas is released during

photosynthesis.The chemical reaction for photosynthesis is-

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

The process of photosynthesis takes place in the green leaves of

plants.

Conditions necessary for

PhotosynthesisThe presence of-• Sunlight• Chlorophyll• Carbon dioxide and• Water is necessary for the process of

photosynthesis. The photosynthesis will not

occur if any of one material above is absent, and this will ultimately cause the plant to die.

Role of Stomata in the process...• There are a large number of tiny

pores called stomata on the surface of the leaves of plants.

-Uses of stomata:-o It helps in exchange of gases

during respiration and photosynthesis.

o During transpiration, water is lost and cooling of plants takes place.

How plants obtain CO2 and Water??? • CO2 :- Green plants take CO2 from air

through stomatal pore. The opening and closing of stomata is controlled by the guard cells.

• Water:- The water required by the

plants for photosynthesis is absorbed by the roots through the process of osmosis. This water is transported through the xylem vessels to the leaves where it is utilised in photosynthesis.

Site of photosynthesis- Chloroplasts

• Chloroplasts are the organelles in the cells of green plants which contain chlorophyll and where photosynthesis takes place.

• Photosynthesis occurs in the organelles called Chloroplasts present in the photosynthetic cells or mesophyll cells.

Events occur during Photosynthesis-The Photosynthesis takes place in the

following three steps• Absorption of sunlight energy by

chlorophyll and conversion of light energy into chemical energy.• Splitting of water into hydrogen and oxygen by light energy.• Reduction of carbon dioxide by hydrogen to form carbohydrates.

How Photosynthesis occur in desert

plants• The first and second steps of photosynthesis is light dependent. So, termed as light reaction. Whereas, the third step is independent of light. So, is termed as dark reaction.

• In desert plants stomata opens during night and take up Co2 to form a compound which is stored till morning.

• When sunlight appears this compound releases Co2 and using water, glucose is formed.

Some other important material

used during the process...• Apart from sunlight, water,

chloroplast and carbon dioxide, some other materials like nitrogen, phosphorus, iron and magnesium are taken up from the soil for photosynthesis.

• Nitrogen is an essential element used in the synthesis of proteins and other compounds.

#Efforts• Aarushi• Aayush• Akash• Amit• Ananya• Aniket

• Anoushka