This is the correct option. Abscisic acid is not involved in growth promoting activities. It is involved in various growth inhibiting activities such as dormancy and abscission.

This is the correct option as this statement is false about the phase of maturation. The cells have increased vacuolation in elongation phase.

This is the correct option as this is not a change of differentiation. The cells regain the capacity of division under certain conditions in dedifferentiation.

This is the correct option. Water provides the medium for enzymatic activities that is needed for growth. Oxygen helps in releasing metabolic energy essential for growth activities. Nutrient is required by plants for the synthesis of protoplasm and it acts as a source of energy.

This is the correct option as this statement is false. The growth of the given system per unit time expressed as per unit initial parameter is called the relative growth rate.

An example of adenine derivative is kinetin. An example of derivative of carotenoids is abscisic acid. An example of terpene is gibberellic acid.

This is the correct option. Ethylene is responsible for enhancing the respiration rate during ripening of the fruits.

The delay of senescence of leaves and other organs of the plants by cytokinins is called Richmond Lang effect.

 The induction of flowering by prolonged exposure to low temperatures, as during the winter in a temperate climate is called vernalisation.

Phototropins are blue-light receptors which are involved in phototropism. They are basically autophosphorylating protein kinases.

Morphactins include several synthetic fluorine-containing compounds that tend to produce morphological changes and suppress the growth in plants.

 The phenomenon of responding to an external stimulus like light is known as phototropism.

An enzyme that can stimulate germination of barley seeds is α-amylase.

Cytokinins are the phytohormones that stimulate cell division. They prevent the onset of senescence in tissues. 

High temperature denatures enzymes and retards growth of plants. 

 1-naphthaleneacetic acid, NAA is a synthetic auxin.

It is a gaseous plant hormone playing a key regulatory role in ripening of many types of fruits, including banana, apple, pear and melons. It can be produced naturally by ripening fruits or from synthetic sources such as ethephon. 

Vernalisation is the acquisition of a plant's ability to flower or germinate in the spring by exposure to the prolonged cold of winter. Vernalisation activates a plant hormone called florigen present in the leaves, which induces flowering at the end of the chilling treatment. Florigen or flowering hormone is the hypothesised hormone-like molecules responsible for controlling and/or triggering flowering in plants. Florigen is produced in the leaves and acts in the shoot apical meristem of buds and growing tips.

The chemicals required in smaller quantities are called minor nutrients or trace elements. Among the trace elements are boron, manganese, copper, iron and zinc. Boron is essential for the growth of higher plants. 

Gibberellins are defined as a class of related plant hormones that stimulate growth in the stem and leaves.