explain photosynthesis ESchooltoday Home, All Lessons
 

OTHER LESSONS Wins Forces Energy Genetics reproduction Ecosystems
Asexual Reproduction
Clouds
Charact' of Living Things
Ecosystems
Elements, mixtures and compounds
Electricity

Energy
Forces
Genetics

Needs of Living Things
Nutrients in Food
Photosynthesis
Rock Cycle
Simple Machines
Soils
States of Matter
The Five Senses
Water Cycle
Winds

light and photosynthesis

 

Light and dark reactions in photosynthesis

Photosynthesis is divided into two parts:

1. Light-dependent reactions (light reactions)
2. Light-independent reactions (dark reactions).

what are light and dark reactions

Light reactions need light to produce organic energy molecules (ATP and NADPH). They are initiated by colored pigments, mainly green colored chlorophylls.

Dark reactions make use of these organic energy molecules (ATP and NADPH). This reaction cycle is also called Calvin Benison Cycle, and it occurs in the stroma. ATP provides the energy while NADPH provides the electrons required to fix the CO2 (carbon dioxide) into carbohydrates.


NOTES
This means Dark reactions will fail to continue if the plants are deprived of light for too long since they use the output of the initial light-dependent reactions.

backnext

green plants make their own food