Question

Meroblastic type of embryo development takes place in

• A. Ferns
• B. Selaginella
• C. Pinus
• D. All of the above

Answer 1

The correct option is C Pinus

The embryogeny of Pinus is characteristic, because it consists of two stages:
1. Pro-embryonal stage
2. Embryonal stage
In first stage, the fertilized egg or oospore on development gives rise to embryo. The development of embryo in Pinus is meroblastic as the whole zygote does not take part. The diploid nucleus of the oospore undergoes three mitotic divisions and form eight nuclei. They rearrange into two tiers of four nuclei each as lower and upper tier separated by walls. The upper are free and open and do not take part in development of embryo. The lower tier undergoes further division to form four tiers of four cells each. The lower three tiers are open and helps in transfer of food materials from oosphere to developing embryo. This group of 16 cells arranged in four tiers is called pro-embryo.

So, the correct answer is 'Pinus'