Which of the following statements are correct?
(A) The embryo develops at the micropylar end of the embryo sac where the zygote is situated.
(B) The early stages of embryo development (embryogeny) are different in monocotyledons and dicotyledons.
(C) The zygote gives rise to the proembryo and subsequently to the heart-shaped, globular and mature embryo.
(D) Most zygotes divide only after a certain amount of endosperm is formed.
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → A and D only
The zygote lies at the micropylar end of the embryo sac, and the embryo develops there. Most zygotes wait until some endosperm has formed, which gives the embryo assured nutrition. The early stages of embryo development are similar in monocots and dicots.
(A) The embryo develops at the micropylar end of the embryo sac where the zygote is situated. — True. The embryo grows from the zygote, which lies at the micropylar end.
(B) The early stages of embryo development (embryogeny) are different in monocotyledons and dicotyledons. — False. The early stages of embryogeny are similar in both monocots and dicots, though the seeds differ greatly.
(C) The zygote gives rise to the proembryo and subsequently to the heart-shaped, globular and mature embryo. — False. The order is proembryo, then globular, then heart-shaped and finally the mature embryo.
(D) Most zygotes divide only after a certain amount of endosperm is formed. — True. This is an adaptation to provide assured nutrition to the developing embryo.
So only A and D are correct.
NCERT Extract:
Embryo – “Embryo develops at the micropylar end of the embryo sac where the zygote is situated. Most zygotes divide only after certain amount of endosperm is formed. This is an adaptation to provide assured nutrition to the developing embryo. Though the seeds differ greatly, the early stages of embryo development (embryogeny) are similar in both monocotyledons and dicotyledons. Figure 1.13 depicts the stages of embryogeny in a dicotyledonous embryo. The zygote gives rise to the proembryo and subsequently to the globular, heart-shaped and mature embryo.”