(C) respiration (D) photosynthesis.- A plant bends towards the source of light when exposed to the
light on only one side. Which of the following is the best explanation of
the phenomena?
(A) It needs light for photosynthesis
(B) The apices of their stems are attracted by light
(C) Some auxin accumulates on the shaded side to induce greater cell
elongation on that side
(D) Light stimulates the cells on the illuminated side to increase in
length - The movement of plant organs in response to the force of gravity is
called
(A) hydrotropism (B) geotropism (C) heliotropism (D)
phototropism - A high concentration of synthetic auxins is generally used for
(A) wee control (B) enhancing root initiation
(C) controlling of cell enlargement (D) preventing the growth of
the lateral buds. - Gibberellic acid has been successfully employed to induce flowering
(A) in long day plants under short day conditions (B) in short day
plants under long day conditions
(C) for some plants (D) none of the above - Cytokinins are known to
(A) inhibit cytoplamic movement (C) help in retention of
chlorophyll
(C) influence water movement (D) promote abscission layer
formation - Ethylene is a
(A) solid hormone (B) gaseous enzyme (C) gaseous