In plants,the uptake of $CO_2$ and the release of $O_2$ is a process called .........

Which of the following groups of organisms does not produce $O_2$ during photosynthesis?

$A -$ Productivity of $C_3$ plants is higher than $C_4$ plants.
$R -$ Photorespiration occurs in $C_3$ plants.

Read the following table and choose the correct pair.
$I$. $DCMU$ Herbicide: Inhibitor of non-cyclic electron transport
$II$. $PMA$ Fungicide: Reduces transpiration
$III$. Colchicine Alkaloid: Causes male sterility
$IV$. Soilrite Sodium alginate: Encapsulation of somatic embryos

Which of the following statements is correct regarding $C_4$ plants?

Which of the following pairs is incorrect?