Which isotope is used to study photosynthesis?

Most of the plants contain a green colouring pigment which is responsible for photosynthesis. This pigment was named chlorophyll by

Explain the experiment of Julius von Sachs.

If in a photosynthetic system,${H_2O}^{18}$ is provided,what will be the type of oxygen released in the process?

Two plants $A$ and $B$ are supplied with $CO_2$ with $H_2O^{18}$ and $CO_2^{18}$ with $H_2O$ respectively. Which of the following plants releases $O^{18}$ type oxygen in photosynthesis?

What is the byproduct of bacterial photosynthesis?