1. The embryo sac is developed from a single megaspore. Its antipodals disorganize early. The micropylar end becomes bulbous, while the chalazal end becomes long and narrow and is covered by a ...

The development of the embryo sac continues and proceeds up to about the receptive stage of the stigma. 2. The ovules are cauline, arising from the central axis of the flower. The floral axis bulges ...

The yolk sac functions as nourishment for the developing embryo and can usually be seen by five-and-a-half to six weeks gestational age on a transvaginal ultrasound. Having a gestational sac doesn ...

Conjoined fetuses are a rare type of identical twins that share a placenta and an amniotic sac, when the embryo divides at 13-15 days from conception. The incidence ranges from 1/50,000-1/100,000 ...

In the mouse developing embryo, she previously demonstrated a bias at the two ... and the hypoblast, or the yolk sac. When they tracked GFP expression, the team found that one population of cells ...

An anembryonic pregnancy, also known as a blighted ovum, occurs when a fertilised egg implants in the uterus but does not develop into an embryo. "Although the gestational sac forms, it remains ...

The PHS Policy covers all live vertebrate animals. If an embryo hasn't hatched yet, or an early-larval-stage fish hasn't used up its yolk sac yet, is it not still a vertebrate animal? My facility ...