General
✓✗One of the synthetic auxins is
- IAA
- IBA
- GA
- NAA
General
✓✗The arrangement of growth phases from the apex of a root backwards is
- maturation, elongation, meristematic
- elongation, meristematic, maturation
- meristematic, elongation, maturation
- meristematic, maturation, elongation
General
✓✗Growth in living organisms is best defined as
- a temporary increase in size caused by absorption of water
- a reversible increase in the dry weight of a plant
- any change in the shape of a cell
- an irreversible, permanent increase in size
General
✓✗The mathematical expression for exponential (geometric) growth is
- W1 = W0 + rt
- Lt = L0 + rt
- W1 = W0 ert
- W1 = W0 / rt
General
✓✗Which of the following statements about auxins is incorrect?
- Auxins induce parthenocarpy in tomato and similar plants.
- Auxins initiate rooting in stem cuttings used for propagation.
- Auxins promote the abscission of young fruits at early stages.
- Auxins control xylem differentiation and help in cell division.
General
✓✗2,4-D is widely used to kill
- insects
- monocotyledonous crops
- dicotyledonous weeds
- fungi
General
✓✗The increase in protoplasm during growth is difficult to measure directly. Therefore, growth is measured by
- measuring the intensity of the green colour of the leaves
- counting the number of stomata on the lower surface
- counting the chloroplasts in a few cells of the organ
- a proportional quantity such as fresh or dry weight
General
✓✗Which of the following statements about the sigmoid growth curve are correct?
A. It has a lag phase, a log phase and a stationary phase.
B. Growth is fastest in the lag phase.
C. It is typical of most organisms in their natural environment.
D. It results from arithmetic growth.
Choose the correct answer from the options given below.
A. It has a lag phase, a log phase and a stationary phase.
B. Growth is fastest in the lag phase.
C. It is typical of most organisms in their natural environment.
D. It results from arithmetic growth.
Choose the correct answer from the options given below.
- B and D only
- A, B and C only
- A, C and D only
- A and C only
General
✓✗Which of the following is a growth-promoting activity of PGRs?
- Induction of dormancy
- Abscission of leaves and fruits
- Pattern formation and tropic growth
- Response to wounds and stresses
General
✓✗Senescence of leaves is delayed by one PGR and promoted by another. These are, respectively,
- ethylene and gibberellin
- abscisic acid and cytokinin
- ethylene and cytokinin
- cytokinin and ethylene
General
✓✗Water provides the medium for
- synthesis of oxygen in mitochondria
- enzymatic activities needed for growth
- cell wall lignification only
- light absorption by chlorophyll
General
✓✗Cut or excised leaves remain green for long if induced to root or dipped in
- auxins
- ethylene
- gibberellins
- cytokinins
General
✓✗Match List I with List II.
Choose the correct answer from the options given below.
| List I (crop and aim) | List II (PGR used) |
| A. Sugarcane - longer stem | I. IBA |
| B. Pineapple - synchronised fruit-set | II. Ethephon |
| C. Rose - rooting of stem cuttings | III. Ethylene |
| D. Tomato - faster ripening | IV. Gibberellin |
- A-II, B-III, C-I, D-IV
- A-IV, B-III, C-I, D-II
- A-III, B-IV, C-I, D-II
- A-IV, B-I, C-III, D-II
General
✓✗Ethylene breaks seed and bud dormancy and initiates germination in
- pea seeds
- rice grains
- wheat grains
- peanut seeds
General
✓✗Match List I with List II.
Choose the correct answer from the options given below.
| List I (plant) | List II (feature) |
| A. Buttercup | I. Juvenile and mature leaves differ |
| B. Larkspur | II. Ethylene elongates internodes |
| C. Deep water rice | III. Leaves in air and in water differ |
| D. Cucumber | IV. Ethylene promotes female flowers |
- A-III, B-I, C-II, D-IV
- A-I, B-III, C-II, D-IV
- A-III, B-I, C-IV, D-II
- A-II, B-I, C-III, D-IV