Question
Question: Endosperm polyembryony is type of A) Adventive polyembryony B) True polyembryony C) False pol...
Endosperm polyembryony is type of
A) Adventive polyembryony
B) True polyembryony
C) False polyembryony
D) Gametophytic polyembryony
Solution
When two or more than two embryos develop from a single fertilized egg or the occurrence of multiple embryos in a seed is known as polyembryony. The results in forming two identical twins for the case of humans. This phenomenon is found in both plants and animals.
Complete answer:
Let's discuss the given option and find out the correct answer.
A) Adventive polyembryony:- Normally embryos develop in the ovule and embryo sac. Now if the embryo develops in a somatic cell and it is found in the nucellus or found in chalaza and this type of cell develops in the embryo then the cell is called an adventitious embryo or if the extra embryos develop from the tissues outside the embryo sac, it is called adventive polyembryony. it is found in the plants. Hence option A is incorrect.
B)True polyembryony:-In this type, within a single embryo sac more than one embryos are formed. From the cleavage of egg or zygote the extra embryos may arise.From the synergids or antipodal cells or from the endosperm as all of these lie inside the embryo sac. Hence option B is correct.
C)False polyembryony:- When two or more embryos develop from different embryo sacs then it is called as False polyembryony .The extra embryos may develop from a different megaspore mother cell or from another megaspore derived from megaspore mother cell. Hence option C is incorrect.
D)Gametophytic polyembryony:-Polyembryony can also be gametophytic and sporophytic. Gametophytic polyembryony is ,When the extra embryos arise from gametophytic cells of the ovule. Sporophytic polyembryony is when they are derived from zygote or proembryo or from initial sporophytic cells of the embryo.
Hence option ‘B’ True polyembryony is the correct answer.
Note: The animal kingdom is the nine-banded armadillo is the best example of Polyembryony . It is a medium-sized mammal found in certain parts of America. This wild species gives birth to identical quadruplets.