Photosynthesis is a vital biological process that occurs in plants, algae, and some bacteria. In this lesson, we will explore the basic concepts of photosynthesis, its history, and its impact on the world.

Concepts of Photosynthesis

Photosynthesis is the process by which green plants and some other organisms use sunlight to synthesize foods with the help of chlorophyll. The process involves the conversion of light energy into chemical energy, which is stored in the form of organic compounds such as glucose.

The process of photosynthesis can be divided into two stages:

The light-dependent reaction – occurs in the thylakoid membranes of the chloroplasts, where light energy is converted into chemical energy in the form of ATP and NADPH.

The light-independent reaction or Calvin cycle – occurs in the stroma of the chloroplasts, where CO2 is fixed and converted into glucose.

History of Photosynthesis

The concept of photosynthesis was first introduced by Jan Ingenhousz in 1779, who discovered that plants produce oxygen in the presence of sunlight. Later, in the 19th century, Julius von Sachs and Theodor Engelmann made significant contributions to our understanding of photosynthesis, including the discovery of chloroplasts and the role of different wavelengths of light in photosynthesis.

Impact of Photosynthesis

Photosynthesis has had a profound impact on the world, with its importance in sustaining life on Earth. Some of the most significant impacts include:

Oxygen production – Photosynthesis is responsible for producing the majority of the Earth’s oxygen, making it a crucial process for the survival of life.

Carbon sequestration – Photosynthesis plays an important role in mitigating the effects of climate change by absorbing carbon dioxide from the atmosphere.

Food production – Photosynthesis is the primary source of energy for most food chains, making it essential for food production and human survival.

Ancient Carthage

The Human Body