Short Day Plants

Q.

What are the 7 characteristics of pea plants?

Q. A plant is kept in darkness for 24 hours and a flash of light is provided in dark period. The plant shows flowering. This plant should be a:

1. Long day plant
2. Short day plant
3. Day neutral plant
4. $C_4$ plant

Q.

'Both a short day plant and a long day plant can flower simultaneously in a given place'. Explain.

Q.

It takes a very long time for pineapple plants to produce flowers. Which combination of hormones can be applied to artificially induce flowering in pineapple plants throughout the year to increase yield?

1. Auxin and Ethylene

2. Gibberellin and Cytokinin

3. Gibberellin and Abscisic acid

4. Cytokinin and Abscisic acid

Q. The critical photoperiod for two flowering plants X and Y are 10 hours. At 14 hours of light per day, plant X flowers but there are no flowers on Y. Can you categorize the two plants according to their photoperiodic response?

1. X-Short day plant, Y-Day neutral plant
2. X-Long day plant, Y-Short day plant
3. X- Short day plant, Y- Long day plant
4. X- Long day plant, Y-Day neutral plant

Q. Morphine is obtained from

1. Curcuma longa
2. Rauwolfia serpentina
3. Papaver somniferum
4. Ferula Asafoetida

Q.

Write a short note on polymorphism.

Q.

Winter varieties are usually planted in:

1. Summer

2. Spring

3. Winter

4. Autumn

Q.

	Emasculation is part of A Hybridization B Pure line selection C Mass selection D Clonal selection

Q. Sir, A flash of red light followed by flash of far red light given during the middle of night to a Short day plant, then what will happen and why?

Q. If the plant produces unisexual female flowers, which of the following processes of artificial hybridisation is carried out?
a) Emasculation and bagging
b) Only emasculation
c) Only bagging
d) None of the above
[1 mark]

Q.

Give one example of unisexual species.

Q.

One set of a plant was grown at 12 hours a day and 12 hours night period cycles and it flowered while in the other set night phase was interrupted by a flash of light and it did not produce a flower. Under which one of the following categories will you place this plant?

1. Darkness neutral

2. Day neutral

3. Short day

4. Long day

Q. A horticulturalist kept tobacco plants in short day conditions during the long day season. State its effect on flowering specifying the reason.

Q. Define the term 'double fertilisation'.

Q. When night temperature is low during winter season, the size of potato tuber will

1. increase
2. decrease
3. no effect
4. Both (a) and (b)

Q. Treatment of seeds at low temperature under moist conditions to break its dormancy is called

1. chelation
2. vernalization
3. scarification
4. stratification

Q. Nicotiana sylvestris flowers only during long days and N. tobacum flowers only during short days. If raised in the laboratory under different photoperiods, they can be induced to flower at the same time and can be cross fertilized to produce self-fertile offspring. What is the best reason for considering N. sylvestris and N.tobacum to be separate species?

1. They are physiologically distinct.
2. They are morphologically distinct.
3. They cannot interbreed in nature.
4. They are reproductively distinct.

Q. Nicotiana sylvestris flowers only during long days while Nicotiana tobacum flowers only during short days. If raised in the laboratory under different photoperiods, they can be induced to flower at the same time and can be cross fertilized to produce self-fertile offsprings.
What is the best reason for considering N. sylvestris and N. tobacum to be separate species?

1. They are physiologically distinct
2. They are morphologically distinct
3. They can interbreed in nature
4. They are reproductively distinct

Q. Match the terms to these definitions.
Abscission, apical dominance, biological dock, circadian rhythm, vernalization, dormancy, ethylene, germination, gibberellin, geotropism, photoperiodism, senescence
.......... Relative lengths of daylight and darkness that affect the physiology and behaviour of an organism.

Q.

The phase of growth which is the first phase and represents lag phase of growth curve is

1. Formative phase

2. Cell enlargement phase

3. Maturation phase

4. Stationary phase

Q. A plant is kept in darkness for 24 hours and a flash of light is provided in dark period. The plant shows flowering. This plant should be a:

1. Long day plant
2. Short day plant
3. Day neutral plant
4. $C_4$ plant

Q. Internodal elongation is stimulated by

Q. One set of the plants was grown at 12 hours light and 12 hours dark period cycles and it flowered. Another set of plants were treated with dark phase interrupted by flash of light and it did not flower. Under which one of the following categories will you place the second set of plants?

1. Long day
2. Darkness neutral
3. Day neutral
4. Short day

Q. Nicotiana sylvestris flowers only during long days while Nicotiana tobacum flowers only during short days. If raised in the laboratory under different photoperiods, they can be induced to flower at the same time and can be cross fertilized to produce self-fertile offsprings.
What is the best reason for considering N. sylvestris and N. tobacum to be separate species?

1. They are physiologically distinct
2. They are morphologically distinct
3. They can interbreed in nature
4. They are reproductively distinct

Q. Read the following statements and tick mark the correct option from the codes given below:

1. I and II are correct
2. II and III are correct
3. III and IV are correct
4. All of the above

Q. What is the meaning of Double fertilization process?

Q. Double fertilisation is

1. Fusion of two male gametes with one egg
2. Fusion of one male gamete with two polar nuclei
3. Fusion of two male gametes with two different eggs
4. Syngamy and triple fusion

Q. Value based questions.
If a short-day plant is grown under conditions of long nights and short days and the dark period is interrupted in the middle by a brief exposure to red light, will the plant flower?

Q. Which of the following is a day neutral plant?

1. Maize
2. Paddy
3. Cucumber
4. All of the above