Plant Growth and Development - Online Test
Q1. Abscissic acid is also known as
Answer : Option D
Explaination / Solution:
ABA stimulates the closure of stomata in the epidermis and increases the tolerance of plants to various kinds of stresses.Therefore, it is also called the stress hormone.
Q2. In rosette plants, bolting is due to
Answer : Option C
Explaination / Solution:
Gibberellins also promote bolting (internode elongation just prior to flowering) in beet, cabbages and many plants with rosette habit.
Q3. Which plant hormone is named anti-ageing hormone?
Answer : Option B
Explaination / Solution:
A unique role of cytokinins is to produce anti-aging effects on some plant parts. Cytokinins actually provide a younger, healthier look in plants. By adding this hormone to cut flowers, florists are able to slow down the aging process, providing us with prettier flowers for longer.
Q4. In higher plants, the growing apical bud inhibits the growth of the lateral buds. This phenomenon is called
Answer : Option D
Explaination / Solution:
Apical dominance is the phenomenon whereby the main, central stem of the plant is dominant over (i.e., grows more strongly than) other side stems; on a branch the main stem of the branch is further dominant over its own side branchlets.
Q5. Growth regulator ethylene is used for
Answer : Option C
Explaination / Solution:
Ethylene is highly effective in fruit ripening. It enhances the respiration rate during ripening of the fruits.
Q6. Which of the following gibberellic acid is used for malting process in brewing industry?
Answer : Option D
Explaination / Solution:
GA3 is used to speed up the malting process in brewing industry.
Q7. Which of the following hormone is used to kill dicotyledonous weeds?
Answer : Option C
Explaination / Solution:
2, 4 D (2,4-Dichlorophenoxyacetic acid)are widely used as herbicides. It is widely used to kill dicotyledonous weeds, does not affect mature monocotyledonous plants.
Q8. Parthenocarpy can be induced to develop seedless fruit by application of
Answer : Option A
Explaination / Solution:
Auxins (IAA,IBA)also induce parthenocarpy,(Seed less fruits) e.g., in tomatoes.
Q9.
Identify the cytokinin given below.
Answer : Option B
Explaination / Solution:
Cytokinin is of different types. The cytokinin shown above is of kinetin which promotes cell division. It was isolated by Miller and Skoog from autoclaved herring sperm DNA.
Q10. Plant growth regulator that is used in delay in leaf senescence is
Answer : Option B
Explaination / Solution:
Cytokinins help overcome the apical dominance. They promote nutrient mobilisation which helps in the delay of leaf senescence.
