Photosynthesis is a process by which plants and other photoautotrophic organisms can synthesize carbohydrates (glucose) and oxygen using carbon dioxide from the atmosphere through stomata, light energy from the sun, and water from the soil is absorbed by the root hair cells, which is transported through the xylem. Photosynthesis takes place in the chloroplasts of the mesophyll layer of leaves. Light dependent stage of photosynthesis takes place in the thylakoid part of the chloroplast and light independent stage of photosynthesis occurs in the stroma of the chloroplast where many enzymes are used. The word and chemical equation for photosynthesis are given below.
Carbon Dioxide + Water (with light energy)à Glucose + Oxygen
6 CO2 + 6 H2O à C6H12O6 + 6 O2
If these reactants are available, only then the products of photosynthesis would form. This means if there is less carbon dioxide available, then the rate of reaction will slow down, limiting the products of glucose and oxygen. Other limiting factors include temperature and light intensity. The products of photosynthesis can be utilized in the following ways.
Oxygen is produced in the light dependent stage and is released out of the plants through stomata and then living organisms like humans and animals can use it for the process of respiration. Some oxygen can also be used by the plants for cellular respiration during dark periods. Reduced NADPH and ATP are also made in the light dependent stages that are used in Calvin Cycle. These molecules break down carbon dioxide into glucose.
The glucose that the plant makes is utilized by itself and can provide energy to the plant like for respiration. As plants are known as photoautotrophs, they can make their own food, and transport the glucose in plants by phloem. The glucose produced is the starting material for making different compounds, and this phenomenon is known as the “Fate of Glucose”. Glucose can be either stored as starch, an insoluble storage carbohydrate, or it can combine with nitrates from the soil to form amino acids that can be used for synthesis of proteins that can be used in growth and repair, and also can form enzymes. It can also be converted into sucrose that is found in fruits, cellulose that is found in the cell walls providing it structural support. Glucose can also form fats and oil that can be found in the cell membranes of the plant, and nucleic acids like DNA.