Question

Which of the following has a filiform apparatus as a characteristic feature?
(A) Synergids
(B) Generative cell
(C) Nucellar embryo
(D) Aleurone cell

Answer 1

Filiform apparatus can be observed during the development of female gametophyte also known as embryo sac. These structures look like finger-like projections and are found close to the micropylar end.

Complete answer:
Following are the developments that take place in Embryo Sac:
During the development of the female gametophyte, three cells are formed towards the micropylar end.
One of these three cells is grown to be large and more distinct compared to the other two cells. The large cell is known as the egg cell whereas the other two smaller cells are called Synergids. The three micropylar cells are collectively known as the Egg apparatus.
Filiform apparatus are popularly described as finger-like apparatus that is produced from the outer wall of synergids. These projections show special cellular thickening.
Synergids take use of these apparatus in the absorption of food from the nucellus and then transport the food to the embryo sac.
One of the other functions of synergids is the secretion of chemicals in order to attract and guide the pollen tube. It also releases sperm cells.

Therefore, the correct option is (A) Synergids.

Note:
The three cells that are formed towards the chalazal end are known as antipodal cells. These are the haploid cells. At the time of development, the nucleus of the megaspore divides to form two nuclei. The division takes place mitotically. Each nucleus moves towards the opposite poles and divides twice to form four nuclei at each pole. Out of the four nuclei, one nucleus from each pole migrates towards the centre and is known as polar nuclei.