Question

Scotoactive movement of stomata is that
(A) Stomata open at night
(B) Stomata open during the day
(C) Stomata close at night
(D) Stomata open both during day and night

Answer 1

Hint: Conditions or movement of stomata opposite to their natural or normal movement is known as the scotoactive movement of stomata. The normal opening and closing of stomata are known as the photoactive movement of stomata.

Complete step by step answer:
Stomata usually opens at day time and closes at night. This is the normal routine of the plant.
But in some plants stomata open at night as in succulent plants because of high temperature and water scarcity. These types of movements in stomata are called the scotoactive movement of stomata.
For example: Jade plants and many more.
Succulents plants are largely found in dry, sandy, and rocky regions and regions where high temperatures are seen. In these plants, water supply is limited and if stomata will be open at daytime, because of high-temperature lots of water will evaporate and the plant will eventually phase a water scarcity. A general definition of succulents is that they're drought resistant plants within which the leaves, stem, or roots became quite usually fleshy by the event of water-storing tissue. Other sources exclude roots as within the definition "a plant with thick, fleshy and swollen stems and/or leaves, adapted to dry environments".This difference affects the connection between succulents and geophytes. Geophytes are the plants that survive unfavorable seasons as a resting bud on an underground organ. These underground organs, like bulbs, corms, and tubers, are often fleshy with water-storing tissues. Thus if roots are included within the definition, many geophytes would be classed as succulents. Plants adapted to living in dry environments like succulents are termed xerophytes.
So, the correct answer is ‘(A) Stomata open at night '.

Note: Succulent plants are further divided into different classes based on their habitat. Different classes are:-
- Desert Plants: Found in the desert. Example- Golden poppy.
- Rock Plants: Found on rocks. Example-Ice plant.
- Epiphytes: Found on the surface of plants. Example-Spanish Moss.
- Halophytes: Found in salt or water with high salinity at semi-desert or near seashores. Example-Date palm.