Question

Embryo without plumule, cotyledon and radicle is present in:
A. Orchids
B. Orobanche
C. Utricularia
D. All of the above

Answer 1

Hint: The plants belonging to the Family Orchidaceae have an undifferentiated. This means that in the embryo of these plants, the plumule, cotyledon and radicle is absent. The embryo itself undergoes differentiation and forms the different structures of the plant.

Complete answer:
To know the correct answer to the question, we must be well aware of the topic.
The anther and the egg cell fuse inside the ovary and give rise to the zygote. This zygote grows up to become the embryo. The embryo further undergoes differentiation and a plumule and radicle arise on it. The plumule gives rise to the shoot while the radicle gives rise to the root.
The cotyledon is attached to the embryo with the help of the embryonal axis called the tigellum. An embryo having only one cotyledon is known as the monocot while the one having two cotyledons are known as dicots. The point below the attachment of the tigellum to the cotyledon is the hypocotyl from where the radicle arises. The point above the attachment of the tigellum to cotyledon is the epicotyl from where the plumule arises.
The embryo without the plumule, radicle and cotyledon is present in Orchids.

Therefore, the correct answer to the question is option A.

Note: Here it must be noted that the embryos which are present in the Orchid plant are very small in size. The embryo does not differentiate into plumule, cotyledon and radicle. It grows in size, its cell divides and directly forms roots and shoots which grow into different structures.