PHOTOSYNTHESIS IN HIGHER PLANTS (PLANT PHYSIOLOGY)

PHOTOSYNTHESIS AS A MEANS OF AUTOTROPHIC NUTRITION

Photosynthesis is a process of formation of glucose from simple inorganic substances like CO2 and H2O. There are two types of photosynthetic reaction found in nature; Dark Reaction and Light reaction.

SITE OF PHOTOSYNTHESIS

All plants are involved in photosynthesis process.The photosynthesis occur in mesophyll cells of leaves. Chloroplast is the main site where the process of photosynthesis completes by the use of inorganic compounds like Carbon-dioxide and water.

FACTOR AFFECTING PHOTOSYNTHESIS

Many external and internal factors affect the rate of photosynthesis. Some external factors are light, CO2, temperature, water, leaf anatomy and oxygen while internal factors are chlorophyll content and protoplasmic factor. Importance of factors can be demonstrated with the help of experiments.

PIGMENTS INVOLVED IN PHOTOSYNTHESIS

Pigments are molecule that absorb certain wave length of light and reflect all others,. There are two types of pigments; main pigments and accessory pigments.

CHEMIOSMOTIC HYPOTHESIS

Chemiosmotic hypothesis was proposed by Peter Mitchell in 1961 to describe ATP synthesis by way of a proton electro-chemical coupling.

PHOTORESPIRATION

Photorespiration is a biochemical process in plants especially under conditions of water stress and oxygen. RuBisCo is the most abundant enzyme which fixes CO2 during the Calvin cycle.

C3 AND C4 PATHWAY

Melvin Calvin proposed the C3 pathway and showed that the pathway operated in a cyclic manner; RuBP was regenerated. C4 pathway was worked out by Hatch and Slack where Kranz anatomy is found.

CYCLIC AND NON- CYCLIC PHOTOPHOSPHORYLATION

In plants photosynthesis results in the production of ATP and NADPH by two step process is called non- cyclic photophosphorylation.The photophosphorylation occuring in a cyclic electgron transport called cyclic photophosphorylation.

PHOTOCHEMICAL AND BIOSYNTHETIC PHASES OF PHOTOSYNTHESIS

The entire process of photosynthesis takes place in chloroplast.Photosynthesis comprises of two phases; Photochemical phase or light reaction or light dependent process and second phase is the biosynthetic phase or dark reaction of photosynthesis.

Contact

Feel Free To Email Us .At: