Question

Mention the main steps in the process of photosynthesis. Write in short about each step.

Answer 1

Photosynthesis:

1. Photosynthesis is the process of synthesizing glucose by the autotrophs like green plants after utilizing inorganic raw materials.
2. Water (H₂O) and carbon dioxide (CO₂) are the raw materials for photosynthesis.
3. This process generally occurs in the leaves of green plants that contain chlorophyll pigment.
4. The role of chlorophyll is to absorb solar energy and use it for the occurrence of photosynthetic reactions.
5. The overall reaction of photosynthesis is:
   $6{\mathrm{CO}}_2+6{\mathrm{H}}_2\mathrm{O}\underset{\mathrm{Sunlight}}{\overset{\mathrm{Chlorophyll}}{\to }}{\mathrm{C}}_6{\mathrm{H}}_{12}{\mathrm{O}}_6+6{\mathrm{O}}_2$
6. This reaction involves two steps, light and dark reaction.

Light reaction:

1. This reaction is called Hill’s reaction, and it is a light-dependent reaction.
2. This step involves the role of light (photo) and chemicals; thus, it is also called the photochemical phase of photosynthesis.
3. In this step, light energy is absorbed by chlorophyll and utilized to split the water molecules. This leads to the conversion of light energy into chemical energy.
4. ${\mathrm{H}}_2\mathrm{O}\stackrel{\mathrm{Sunlight}}{\to }2{\mathrm{H}}^{+}+\frac{1}{2}{\mathrm{O}}_2+2{\mathrm{e}}^{-}$

Dark reaction:

1. This is the second phase of photosynthesis which is light-independent.
2. The carbon dioxide molecules are reduced to form carbohydrate/glucose molecules (C₆H₁₂O₆) during this reaction.
3. ${\mathrm{CO}}_2\to {\mathrm{C}}_6{\mathrm{H}}_{12}{\mathrm{O}}_6$