Tag: post fertilization - plants

Questions Related to post fertilization - plants

Mature ovary forms the

  1. Seed

  2. Stamen

  3. Pistil

  4. Fruit


Correct Option: D
Explanation:

Fruits are formed by the maturation of one or more ovary. Fruits contain seeds resulting from the maturation of fertilized ovules. However, maturation of seed and fruit can occur in the absence of fertilization. In fleshy fruits, the outer covering is called as pericarp. Pericarp is again made of three layers, the epicarp, which is the outermost layer; the mesocarp, which is the middle layer; and the endocarp, which is the inner layer surrounding the ovary or the seeds. 

So, the correct answer is option D.

Which of the following is a post fertilisation event in flowering plants?

  1. Transfer of pollen grains

  2. Embryo development

  3. Formation of flower

  4. Formation of pollen grains


Correct Option: B
Explanation:
Events in sexual reproduction after the fertilisation are called post-fertilisation events. After fertilisation, a diploid zygote is formed in all sexually reproducing organisms. The process of development of embryo from the zygote is called embryogenesis.
So, the correct answer is 'Embryo development'.

In angiosperms, normally after fertilisation.

  1. The zygote divides earlier than the primary endosperm nucleus

  2. The primary endosperm nucleus divides earlier than the zygote

  3. Both the zygote and primary endosperm nuclei divide simultaneously

  4. Both the zygote and primary endosperm nuclei undergo a resting period


Correct Option: B
Explanation:

Endosperm is the nutritive tissue for the developing embryo and the seedlings. In angiosperm, the endosperm develops from triploid primary endosperm nucleus which is formed as a result of vegetative fertilization, triple fusion or fusion of male gamete with the secondary nucleus of the central cell. Generally, endosperm divides before zygote because it will provide nourishment to the developing zygote.

So, the correct option is 'The primary endosperm nucleus divides earlier than the zygote'

In angiosperms, triple fusion is required for formation of

  1. Embryo

  2. Endosperm

  3. Suspensor

  4. Fruit wall


Correct Option: B
Explanation:
Angiosperms have a unique phenomenon of double fertilisation in which after the release of two male gametes inside the embryo sac by the pollen tube, one male gamete (first male gamete which is closest to the egg) fuses with egg nucleus and this phenomenon is known as fertilisation or syngamy and results in the formation of zygote.
The other male gamete i.e. the second male gamete migrates towards the secondary nucleus (formed from fusion of two polar nuclei) and fuses with it. This phenomenon is known as triple fusion and results in the formation of a triploid primary endosperm mother cell. Primary endosperm mother cell then undergoes further divisions to form endosperm. Hence, triple fusion is required for the formation of endosperm.
So, the correct answer is B.

The wheat grain is a

  1. Fruit

  2. Seed

  3. Embryo

  4. Glume


Correct Option: A
Explanation:

Wheat is a grain, which belongs to the grass family Poaceae or Gramineae. Wheat grain is a fruit (Caryopsis) that produces a dry edible seed which is commonly known as the kernel. Wheat grain is a small edible fruit, usually hard on the outside. Corn, grain sorghum, rice, oats, and rye are other examples of grains.

So, the correct answer is 'Fruit'.

'Sonalika' is a variety of 

  1. Rice

  2. Wheat

  3. Maize

  4. Bajra


Correct Option: B
Explanation:

Sonalika is developed from high yielding , semi dwarf , fertilizer responsive wheat variety .Sonalika is not an Indian wheat variety.

To form 100 angiosperm seeds, how many mitosis are required?

  1. 300

  2. 200

  3. 500

  4. Can't say


Correct Option: C
Explanation:

For the formation of male gametophyte, 1 meiosis and 2 mitoses are required.

and for the formation of female gametophyte 1 meiosis and 3 mitoses are required. 
One angiosperm seed contains 1 male gametophyte and 1 female gametophyte.
So, to produced 1 angiosperm seed 2+3=5 mitosis will be required.
Thus, to produce 100 angiosperm seeds, 100X5=500 mitosis will be required
S.o the correct option is '500'.

After fertilization ______ develops into seed and ovary into fruit.

  1. endosperm

  2. ovary

  3. embryo sac

  4. egg cell


Correct Option: A

After fertilization ________ develops into seed and ______ into fruit.

  1. Endosperm

  2. Ovary

  3. Embryo sac

  4. Egg cell


Correct Option: A

Identify the wrong statements regarding post fertilization development.

  1. The ovary wall develops into pericarp.

  2. The outer integument of the ovule develops into tegmen.

  3. The fusion nucleus (triple nucleus) develops into endosperm.

  4. The ovule develops into seed.

  5. The ovary develops into fruit.


Correct Option: B
Explanation:

After fertilization, the ovule matures into seeds and ovary into fruits. The process of fertilization is unique in angiosperms because it involves syngamy between male and female gametes and triple fusion between a male gamete and a secondary nucleus. Because two fertilization events are involved, it is called as double fertilization. The second fertilization is a fusion between three haploid nucleus (two forming a diploid secondary nucleus and one haploid male nucleus). Hence the secondary fertilization event is called as Triple fusion. It gives rise to a triploid primary endosperm nucleus (PEN). PEN later on gives rise to triploid endosperm. The seed coat forms from the two integuments or outer layers of cells of the ovule, which derive from tissue from the mother plant, the inner integument forms the tegmen and the outer forms the testa. The seed coats of some monocotyledon plants, such as the grasses, are not distinct structures, but are fused with the fruit wall to form a pericarp.