Tag: plant growth and development

Questions Related to plant growth and development

Which of the following statements regarding photoperiodism is false?

vernalisation plant growth growth and development plant growth and development biology

  1. The response of plants to periods of light/day is termed as photoperiodism

  2. The shoot apices cannot perceive photoperiods

  3. In day neutral plants there is no correlation between exposure to light duration and induction of flowering response

  4. Shoot apices modify themselves into flowering apices prior to flowering

  5. The site of perception of light/dark duration is the flower

Show answer
Correct Option: E
Explanation:
Photoperiodism is the response of plants to photoperiods, that is the length of day and night. During photoperiodism, shoot apices modify themselves into flowering apices prior to flowering. However, they do not perceive photoperiods. Rather, the site of perception of light and dark duration are leaves. In day-neutral plants, induction of flowering response does not depend on exposure to light duration. The site of perception of light/dark duration is the leaves.
So, the correct answer is 'The site of perception of light/dark duration is the flower'.

Which is incorrect statement?

vernalisation plant growth growth and development plant growth and development biology

  1. There are no mesodermal cells in pseudocoelomates

  2. There is no body cavity in first triploblastic animals

  3. There is no second opening in diploblastic animal gut

  4. There is no co-ordination between cells of sponges

Show answer
Correct Option: A
Explanation:

Animals have a pseudocoelom that means  “false cavity”, which is a fluid-filled body cavity. Tissue derived from mesoderm partly lines the fluid-filled body cavity of these animals. It is mainly found in Nematoda.

So the correct option is 'There are no mesodermal cells in pseudocoelomates'

Seeds of winter varieties are benefitted by technique

vernalisation plant growth growth and development plant growth and development biology

  1. Senescence

  2. Photoperiodism

  3. Vernalisation

  4. Abscission

Show answer
Correct Option: C
Explanation:

Vernalisation is the phenomena in which flowering is induced in the plant by exposing it to low temperatures. Seeds of winter varieties will flower only when they are exposed to cold period early in their development. Artificially, flowering can be induced in spring as well if they are exposed to artificial vernalization. 

Thus, the correct answer is option C.

Vernalisation is seen in

vernalisation plant growth growth and development plant growth and development biology

  1. Sugarbeet

  2. Carrot

  3. Cabbage

  4. All the above

Show answer
Correct Option: D
Explanation:

Vernalization is the process by which plant can be induced to flower by exposing it to prolonged cold or winter. The term was coined by Lysenko in 1928. He stated that certain plants can be made to flower by providing low-temperature treatment to young plants or moistened seeds. Sugarbeet, carrot are biennial plants that require vernalization for flowering.

Thus, the correct answer is option D.

The stimulus of cold treatment (vernalisation) is perceived by

vernalisation plant growth growth and development plant growth and development biology

  1. Leaves

  2. Flowers

  3. Roots

  4. Shoot apices

Show answer
Correct Option: D
Explanation:
Vernalisation is the conversion of winter variety into spring variety by chilling treatment or low temperature. Treatment with low temperature (0-4°C) leads to shortening of vegetative phase and initiation of reproductive phase. The stimulus of cold treatment is perceived by shoot tips, embryo tips and other meristematic regions pf the plant.
So, the correct answer is 'Shoot apices'.

Apple requires a low temperature for flowering and fruiting

vernalisation plant growth growth and development plant growth and development biology

  1. 10$^o$ C

  2. 7$^o$ C

  3. Below 7$^o$ C

  4. 10$^o$ - 15$^o$ C

Show answer
Correct Option: C
Explanation:

Apple grows in low temperature for germination it needs more time as earlier stages are less tolerant to low temperature but flowering starts at the temperature which is around 7 degree or below it that means it needs extreme cold climate to grow.

So the correct option is 'Below $7^o$ C'.

The term 'Yarovization' was coined by

vernalisation plant growth growth and development plant growth and development biology

  1. Lysenko

  2. Klebs

  3. Yabuta

  4. Kogl and Haagen-Smit

Show answer
Correct Option: A
Explanation:

Yarovization is the process by which plant can be induced to flower by exposing it to the prolonged cold of winter. After this, plants show flowering. The term was coined by Lysenko in 1928.  He stated that certain plants can be made to flower by providing low temperature treatment to young plants or moistened seeds. Other terms like vernalization, jarovization, springification were also coined for the same phenomenon. However, today the most accepted term is vernalization.

Thus, the correct answer is A 'Lysenko'

Potato is _________ for flower formation but _________ for tuberisation.

vernalisation plant growth growth and development plant growth and development biology

  1. LDP, SDP

  2. SDP, LDP

  3. LDP, day neutral

  4. SDP, day neutral

Show answer
Correct Option: A
Explanation:

In the case of potato, it requires more photoperiod to induce flowering. Whereas for the formation of tuber, it requires very less photoperiod. Thus, it is told that potato is LDP for inducing flowering; but SDP for tuber formation. The flower-inducing florigen and tuber-inducing tuberigen signals are functionally exchangeable. Flowering and tuberization are distinct reproduction strategies, both of which involve the sensing of the photoperiod and generation of a signal in the leaves (process called as induction), the subsequent transport of the signal (known as florigen or tuberigen), and the response in a distant organ, the vegetative meristem, or stolon tips (also called evocation).

Cabbage is a biennial plant which produces flowers in the second year of growth. In an attempt to make it flower in a single year, four potted plants (I, II, III, and IV) of cabbage were subjected to different temperatures for several days given in the table.

Potted plant Temperature
I $5^o C$
II $20^o C$
III $30^o C$
IV $25^o C$

Which potted plant will show flowering?

vernalisation plant growth growth and development plant growth and development biology

  1. I

  2. II

  3. III

  4. IV

Show answer
Correct Option: A
Explanation:
The low temperature required for vernalization is usually $0^o-5^oC$. In nature, the plants requiring vernalization are commonly biennials (e.g., cabbage, sugar canes), which complete their life cycle in two years. They germinate and grow vegetatively in the first year and produce flowers in the second year of growth. These plants fulfill their cold requirement during winters. However, such-biennial plants can be made to flower in one growing season by providing low-temperature treatment (i.e., $0^o-5^oC$ temperature) to young plants or moistened seeds.
So the correct answer is 'I'.

Biennials get changed into annuals by

vernalisation plant growth growth and development plant growth and development biology

  1. Hormones

  2. Photoperiodism

  3. Grafting

  4. Vernalisation

Show answer
Correct Option: D
Explanation:
Vernalization is the process by which plant can be induced to flower by exposing it to the prolonged cold or winter. The term was coined by Lysenko in 1928. He stated that certain plants can be made to flower by providing low temperature treatment to young plants or moistened seeds. Biennial plants are changed into annual plants by the process of vernalisation and induces flowering.
Thus, the correct answer is option D.