Abscisic acid is known as the stress hormone because it

  • breaks seed dormancy

  • induces flowering

  • promotes leaf fall

  • promotes closure of stomata

Which of the following plant growth regulators (PGRs) promotes root initiation, flowering and
induced parthenocarpy?

  • Gibberellin

  • Auxin

  • Cytokinin

  • Ethylene

Vernalisation is subjected to plants growing in ?

  • tropical

  • sub tropical areas

  • temperate areas

  • hot region/arctic region

Gibberellins can promote seed germination because of their influence on

  • rate of cell division

  • production of hydrolyzing enzymes

  • synthesis of abscisic acid

  • absorption of water through hard seed coat

One hormone hastens maturity period in juvenile conifers, a second hormone controls xylem differentiation, while the third hormone increases the tolerance of plants to various stresses.They are respectively:-
  • Gibberellin, Auxin, Ethylene

  • Auxin, Gibberellin, Cytokinin

  • Gibberellin, Auxin, ABA

  • Auxin, Gibberellin, ABA

Identify the incorrect statement about ABA growth regulator.

  • It increases the tolerance of plants against different stresses.

  • It acts as general plant growth inhibitor and inhibitor of metabolism.

  • It helps in seed maturation and dormancy.

  • It promotes morphogenesis and differentiation of shoots.

Which of the following plant growth hormone increase the yield of sugar by increasing the length of stem in sugarcane?

  • Cytokinin

  • Ethylene

  • Gibberellic acid

  • Auxin

In the process of apical dominance, lateral buds are unable to grow in the presence of apical bud. This is due to:-
  • less amount of cytokinins in lateral buds

  • more amount of cytokinins in lateral buds

  • less amount of auxin in lateral buds

  • more amount of auxin in lateral buds

Refrigerated fruits maintain flavour and taste for longer period due to:-

  • non-availability of O2

  • the presence of excess of CO2

  • the presence of excess humidity

  • slower rate of respiration

The biological clock measures the length at each night by the?

  • relative amount of red absorbing and far-red absorbing phytochrome present at dawn

  • amount of far-red absorbing phytochrome at dusk

  • relative amount of red absorbing and far-red absorbing phytochrome at mid day

  • rate at which are kind of phytochrome is converted to the other

A physiological response of plants to the duration of light and darkness is a:-

  • daily phase cycle

  • circadian rhythms

  • biological clock

  • photoperiodism

ABA is involved in?

  • shoot elongation   

    (2) increased cell division

  • 2

  • dormancy of seed 

    (4) root elongation

  • 4

Hypothetical plant hormones are:-

  • florigen                   

  • vernalin

  • florigen and vernalin 

  • auxin

The application of synthetic plant hormone like IAA, IBA and NAA are best described as:-

  • prevent early fruit fall before harvesting and is used to produce parthenocarpic fruit

  • prevent early fruit fall only

  • to produce both seed less fruits and fruits with seeds

  • to produce larger fruit

Organogenesis or morphogenesis in tissue culture is controlled/regulated by phytohormones the credit of this important discovery goes to

  • Skoog and Miller (1957)

  • Guha and Maheswari (1964)

  • Calvin and Benson (1894)

  • Halperin and Wetherall (1964)

Which one plant movement is unidirectional?

  • Phototaxis

  • Chemotaxis

  • Both (a) and (b)

  • Thigmotrophism

Natural cytokinins are sythesized in tissue that are:-

  • senescent

  • dividing rapidly

  • storing food material

  • differentiating

Match each item in Column I with one item in Column II and chose your answer from the codes given below:
Column I                                                        Column II
I. Malting in brewing                                       1. Cytokinins
II. Parthenocarpy in tomatoes                          2. Gibberellins
III. Overcoming apical dominance                    3. Ethylene
IV. Female flowers in Cucumbers                      4. Auxins
Codes:

  • . 4 2 3 1
  • . 2 1 4 3
  • . 2 4 1 3
  • . 4 2 1 3

Match each item in Column I with one item in Column II and chose your answer from the codes given below:
Column I                       Column II
I. Short day plant           1. Rose
II. Long day plant           2. Dianthus
III. Day neutral plant      3. Tobacco
Codes:
       I    II   III
  • .    1    2   3
  • .    2    3   1
  • .    2    1   3
  • .    3    2   1

Ethephon

Which of the following is not correct?

  • In an aqueous solution, it is readily absorbed and transported within the plant and release ethylene slowly

  • Hastens fruit ripening in tomatoes and apples

  • Accelerates abscission in flowers and fruits

  • Promotes male flowers in cucumbers thereby increasing the yield

With respect to photoperiodism, the short day plant, the long day plant and day neutral plant are represented respectively by:
  • A, B and C
  • B, A and C
  • C, B and A
  • A, C and B

Plant Growth Regulators (PGRs) are not

  • Very less in number in plants

  • Small and simple molecules

  • Diverse chemical composition

  • Plant hormones or phytohormones

N6- furfurylamino purine and kinetin are derivative of …….

  • Indol compounds

  • Adenine

  • carotenoids

  • Terpenes

Abscisic Acid and ABA are derivative of…..

  • Indol compounds

  • Adenine

  • carotenoids

  • Terpenes

C2H4 or Ethylene are …...or derivative of….

  • Indol compounds

  • Gases

  • carotenoids

  • Terpenes

In the living plant body, the PGRs can be broadly divided into two groups. This classification is actually based on

  • Function

  • Structure

  • Metabolism

  • Kinetin

Plant growth promotors are not involved in

  • Cell division, cell enlargement

  • Pattern formation, seed formation

  • Dormancy, Abscission

  • Fruiting and Flowering

Plant growth promotor is not

  • Auxins

  • Gibberellins

  • Cytokinins

  • ABA

The PGRs of the other group which play an important role in plant growth inhibiting activities is not

  • Ethylene

  • ABA

  • GA

  • All of these

Which of the following hormones is common in both the categories of plant promotor and plant inhibitor?

  • GA

  • ABA

  • Auxin

  • Ethylene

0:0:1


Answered Not Answered Not Visited Correct : 0 Incorrect : 0

Practice Botany Quiz Questions and Answers