Both nyctinasty and thigmonasty are observed in

The role of ethylene and abscisic acid is both positive and negative. Justify the statement.

Which one of the following pairs of plant hormones inhibits flowering in some plants?

Pick out the correct statements.
$I.$ Cytokinins especially help in delaying senescence.
$II.$ Auxins are involved in regulating apical dominance.
$III.$ Ethylene is especially useful in enhancing seed germination.
$IV.$ Gibberellins are responsible for immature falling of leaves.

In blue-violet colour light:

Match column-$I$ with column-$II$ and select the correct option using the codes given below.

Column-$I$	Column-$II$
$A$. Cytokinin	$i$. Stimulates closure of stomata
$B$. Ethylene	$ii$. Increases stem length
$C$. Gibberellin	$iii$. Promotes lateral shoot growth
$D$. Abscisic acid	$iv$. Found in large amounts in tissues undergoing senescence