Question. Cytokinins are formed primarily in which area of the plant?
(a) Tips of shoot
(d) Lateral buds and leaves
Question. Natural cytokinins are synthesised in
(a) Root apices
(b) Developing shoot buds
(c) Young fruits
Question. Zeatin is
(a) An auxin
(b) a GA
(c) a cytokinin
Question. Cytokinins help to produce all except
(a) New leaves
(b) Chloroplast in leaves
(c) Lateral shoot growth and adventitious shoot formation
(d) Rooting on stem cut
Question. C2H4 is synthesised in large amount by-
(a) Shoot tip
(b) Root tip
(c) Young leaves
(d) Tissues undergoes senescence and ripening fruits
Question. During ripening of the fruits, rate of respiration is increased under the influence of hormone. The hormone is
Question. Seed dormancy is regulated by-
Question. The most widely used compound as a source of C2H4 is
Question. Which hormone promotes female flowers in cucumber?
Question. Long day plants flower specially when the?
(a) Light period is lesser then some critical length
(b) Light period is grater then some critical period
(c) Dark period is less then some critical length
(d) Dark period is more then some critical length
Question. The following diagram shows four coleoptile set up at the start of an experiment
Which two coleoptile will both bend towards the light source?
(a) 1 and 2
(b) 1 and 4
(c) 2 and 3
(d) 3 and 4
Question. Removal of auxin source demonstrates that leaf abscission is _____ by auxin, and apical dominance is _____ by auxin
(a) Promoted, promoted
(b) Inhibited, inhibited
(c) Promoted, inhibited
(d) Inhibited, promoted
Question. Branching is inhibited by _____ from the tip of a growing shoot but this effect is encountered by _____ from the root
(a) Cytokine, auxin
(b) Auxin, Cytokine
(c) GA, Cytokine
Question. Which of the following plant hormones can cause the base of a shoot to form new early stage, to be used as herbicide / weedicide, also controls xylem differentiation and helps in cell division?
Question. Removal of shoot tips (decapitation) means loss of apical dominance and it is widely applied in
(a) Tea plantation
Question. Which one(s) is acidic in nature?
Question. Which GA was the first Giberrellin to be discovered?
Question. The fruits can be left on the tree longer so as to extend the marked period. This is due to which function of GA?
(b) Delay senescence
(c) Internodal elongation
Question. Spraying surgarcane with gibberellin increases the yield by as much as 20 tonnes per acre. GA makes this possible
(a) By improving the quality of fruit
(b) By making plants with rosette habit
(c) By internodal elongation
Question. Which one is false?
(a) GA3 is used to speed up the malting process in brewing industry
(b) Spraying juvenile conifers with GA3 hastens the maturity, thus leading to early seed production
(c) GA3 is commercially available gibberellin
(d) GA3 cannot increase the length of internode in sugarcane
Question. Two cytokinins are kinetin and Zeatin. What is the difference between the two?
(a) Kinetin is the active from of zeatin
(b) Zeatin is the active from of kinetin
(c) Zeatin is synthetic cytokininand kinetin is naturally occurring
(d) Zeatin is naturally occurring plant cytokinin, kinetin is not