3. Points of Discussion
• What is chloroplast.
• Distribution .
• Chloroplast as semiautonomous organelle.
• Chemical composition.
• Ultra structure
• Biogenesis of chloroplast
4. what is chloroplast
• Chloroplast are the organelles present within plants and algae which carry
out photosynthesis.Where solar energy is utilize to fix CO2 to synthesize
carbohydrate.in this process O2 is released.
• Chloroplast are type of plastids.
• Shape varies.
• Contain their own genome.
• They show maternal inheritance.
• The chloroplast remain distributed homogeneously in the
cytoplasm of plant cell.
• The algae usually have a single huge chloroplast the cell of higher
plants have 20-40 chloroplast.
• When the number of chloroplast in inadequate.it is increased by
division when excessive.it is reduced by regeneration.
6. Chloroplast as
• Like the mithochondria the chloroplast have their own DNA,
RNA,and protein synthetic machinery.
• DNA of chloroplast.
• Ris and Plant(1962)reported DNA in chloroplast.it is double helix
and 45 micrometer in length.
• RIBOSOME-70 ribosome
• PROTEIN SYNTHESIS-NDA of chloroplast code for chloroplast
PERCENT DRY WEIGHT COMPONENTS
Protein 35-55 Insoluble 80 percent
Lipids 20-30 Fat 50%
Carbohydrate variable Starch,sugar,phosphate 3-
Chlorophyll 9 Chlorophyll a 75%
Chlorophyll b 25%
Carotenoids 4.5 Xanthophyll 75%
• Absorption of light energy and conversion of it into
• Production of NAPDH2 and evolution of oxygen through the
process of photosys of water.
• Production of ATP by photophosphorylation.
• NADPH2 and ATP are the assimilatory powers of
Photosynthesis is a process used by plants and other
organisms to convert light energy into chemical energy
that, through cellular respiration, can later be released to
fuel the organism's metabolic activities.
6CO2 + 6H2O → C6H12O6 + 6O2
PHOTOSYNTESIS REACTION consist of two parts.
1. Light reaction
2. Dark reaction
11. LIGHT DEPENDENT
The light-dependent reaction is a photochemical
reaction taking place in the thylakoid membranes of
chloroplasts, where light energy is transformed into
adenosine triphosphate (ATP) and nicotinamide adenine
dinucleotide phosphate (NADPH)
Photosystems are functional and structural units of
protein complexes involved in photosynthesis. Together
they carry out the primary photochemistry of
photosynthesis: the absorption of light and the transfer of
energy and electrons.