gametophyte — specifically termed a megagametophyte — is also called the embryo sac in angiosperms. The megagametophyte produces an egg cell for the purpose...

is reduced to only a few cells, and is sometimes called the embryo sac. A typical embryo sac contains seven cells and eight nuclei, one of which is the...

The yolk sac is a membranous sac attached to an embryo, formed by cells of the hypoblast layer of the bilaminar embryonic disc. This is alternatively...

The gestational sac is the large cavity of fluid surrounding the embryo. During early embryogenesis, it consists of the extraembryonic coelom, also called...

The amniotic sac, also called the bag of waters or the membranes, is the sac in which the embryo and later fetus develops in amniotes. It is a thin but...

product of the ripened ovule, after the embryo sac is fertilized by sperm from pollen, forming a zygote. The embryo within a seed develops from the zygote...

the pre-embryo, the amnion, yolk sac and allantois, while the fetal part of the placenta will form from the outer trophoblast layer. The embryo plus its...

nucellus, and the female gametophyte is sometimes called the embryo sac or embryonic sac. Two distinct processes are involved in producing the megagametophyte...

the nuclear cells surrounding the embryo sac start dividing and protrude into the embryo sac and develop into embryos. American Journal of Botany 98(10):...

various other embryos when they first form. It fills with amniotic fluid, which causes the amnion to expand and become the amniotic sac that provides...

legumes, either enlarged antipodal cells in the embryo sac or the production of multiple embryo sacs. There has been a shift from bee pollination to bird...

Fecal sac Gestational sac Greater sac Gular skin or throat sac Ink sac Lacrimal sac, eye-and-nose-associated structure Lesser sac Ovule or embryo sac Pleural...

gestation is characterized by a normal-appearing gestational sac, but the absence of an embryo. It likely occurs as a result of early embryonic death with...

into a fruit. and each ovule into a seed. As the embryo and endosperm develop, the wall of the embryo sac enlarges and combines with the nucellus and integument...

reduced in size, and are represented by the germinated pollen and the embryo sac The sporophyte produces spores (hence the name) by meiosis, a process...

processes and result in varying embryo sacs as well. In Lilium which has a tetrasporic pattern, the central cell of the embryo sac is 4n. Therefore, upon fertilization...

the anther and in the stigma). The female gamete is produced inside the embryo sac of the ovule. In angiosperms the division of a generative cell into two...

(an opening in the ovule wall) and the pollen tube "bursts" into the embryo sac, releasing sperm. The growth of the pollen tube has been believed to depend...

develops into a seed containing the embryo. In flowering plants, the female gametophyte (sometimes referred to as the embryo sac) has been reduced to just eight...

Asteraceae family. Embryo sac development in Chamaemelum differs from that of Anthemis, with Chamaemelum exhibiting monosporic embryo sac formation, while...

definitive yolk sac contributes greatly to the embryo during the fourth week of development, and executes critical functions for the embryo. One of which...

Human embryo of eight weeks. Diagrams to illustrate the development of the greater omentum and transverse mesocolon. Omental bursa (Lesser sac) Omental...

reduced to an eight-celled embryo sac within the ovule inside the ovary of the flower. Oogenesis occurs within the embryo sac and leads to the formation...

associated with the developing embryo, and fetus in humans and other mammals. They are the amnion, chorion, allantois, and yolk sac. The amnion and the chorion...

tissues). It helps the embryo exchange gases and handle liquid waste. The allantois, along with the amnion, chorion, and yolk sac (other extraembryonic...

thinner megasporangium. The embryo sac (megagametophyte) varies by genera, but is mainly tetrasporic (e.g. Fritillaria). Embryo sacs in which three of the four...

eventually aborts). Also, most basal angiosperms still contain the four-cell embryo sac and produce diploid endosperms. Endosperm is the evolutionary remnant...

includes the embryo as well as the embryonic part of the placenta and its associated membranes: amnion, chorion (gestational sac), and yolk sac. "Conceptus"...

membrane around the embryo in mammals, birds and reptiles (amniotes). It develops from an outer fold on the surface of the yolk sac, which lies outside...

the embryo arises from an unfertilized egg within a diploid embryo sac that was formed without completing meiosis. In nucellar embryony, the embryo is...