Which of the following mineral elements is a component of ferredoxin?

Boron in green plants assists in

Which of the following are considered as the roles of iron $(Fe)$ in plants?
$I.$ Important constituent of cytochrome
$II.$ Activator of catalase
$III.$ Essential for chlorophyll synthesis
Choose the correct option

Explain the uses of $K^+$ in plants.

Which mineral is essential for the repair of worn-out cells in our body?

$S$ - Statement: The presence of $Zn$ is essential for the activity of carbonic anhydrase.
$R$ - Reason: The presence of vanadium is essential for the activity of nitrogenase.