$CO_2$ is constantly released in respiration,yet its level remains fairly uniform because:

Statement $P$: During the dark reaction of photosynthesis,ketotriose is synthesized.
Statement $Q$: The sugar present in the structure of $ATP$ is an example of a ketopentose sugar.

How many molecules of water are needed by a green plant to produce one molecule of hexose or to reduce $6$ molecules of $CO_2$?

Consider the following statements.
$I.$ The portion of the spectrum between $300-500 \;nm$ is also referred to as Photosynthetically Active Radiation $(PAR)$.
$II.$ Magnesium,calcium and chloride ions play prominent roles in the photolysis of water.
$III.$ In cyclic photophosphorylation,oxygen is not released (as there is no photolysis of water) and $NADPH$ is also not produced.

Which branch of Botany is concerned with the study of photosynthesis?

Green plants are grown in an aquarium for the purpose of: