Name the scientist who first suggested that plants purify foul air through the bell jar experiment.

The carbon isotope used for the study of photosynthesis is ........

Which isotope is used to study photosynthesis?

Evaluate the following statements regarding $T$. $W$. Engelmann's experiment:
$1.$ $T$. $W$. Engelmann stated that chlorophyll present in algae absorbs light of green and orange colors,splits water molecules by photolysis,and releases $O_2$.
$2.$ Aerobic bacteria accumulate near the algae to utilize the released $O_2$.

$PGA$ was discovered as the first product of $CO_2$ fixation in the photosynthesis of:

The discovery that the first stable product of $CO_2$ fixation in photosynthesis is $3$-phosphoglyceric acid $(PGA)$ was made by whom?