Plant Growth and Development (Class - XI)
Plant Growth and Development (Class - XI)
Questions
Which of the following is an endogenous dormancy?
- Physical dormancy
- Mechanical dormancy
- Chemical dormancy
- Physiological dormancy
The dormancy taking place in non-dormant and post dormant seeds is
- secondary dormancy
- combinational dormancy
- morphophysiological dormancy
- thermodormancy
Which of the following plant hormones restricts the shoot branching?
- Plant peptide hormone
- Nitric oxide
- Strigolactones
- Karrikins
The senescence observed in banana and gladiolus is
- whole plant senescence
- sequential senescence
- shoot senescence
- synchronous senescence
Which of the following movements is/are observed in twiners and climbers?
- Nutation
- Nastic movements
- Movement of variation
- Paratonic movements
With which of the following is Richmond Lang effect associated?
- Stimulation of rosette plants to grow normal
- Inhibition of glycolysis by oxygen
- Inhibition of photosynthesis by oxygen
- Delay of senescence in leaves
What are morphactins?
- Growth retardants
- Synthetic growth regulators
- Phytochromes
- Synthetic enzymes
How does pruning of plants promote branching?
- The activity of ethylene decreases.
- Auxiliary buds get sensitised to gibberellin.
- Auxiliary buds get sensitised to cytokinin.
- The activity of abscisic acid decreases.
Gibberellic acid was first isolated from
- oryza sativa
- zea mays
- fusarium moniliformae
- giberella fujikuroii
Which of the following statements are correct or wrong?
a. The origin of parts or organs and the gross form of the plant is called morphogenesis.
b. The annual plants show unlimited growth.
c. Growth regulators are organic substances synthesised in the plant parts.
d. The pattern of growth is sigmoid in plants or plant parts.
- a and c are correct.
- a and d are correct.
- b and d are wrong.
- c and d are wrong.
Gibberellic acid induces flowering under noninductive photoperiods in long-day plants. However, it is known to replace photoperiodic requirements in some SD plants. The example of such a plant is
- xanthium
- dahlia
- impatiens
- biloxy soyabean
The phenomenon of responding to an external stimulus like light is known as
- phototropism
- geotropism
- thigmotropism
- sensitivity
How many gibberellins have been isolated so far?
- 90
- 91
- 92
- 93
Increase in length of a plant can be measured by an instrument called
- potometer
- manometer
- auxanometer
- respirometer
Hormones are very essential for the growth of both plants and animals. Besides the natural hormones, there are a lot of artificial hormones produced as a result of the progress of modern science. Which hormone helps in the ripening of fruits?
- Auxin
- Ethylene
- Cytokinin
- Florigen