embryo sac cell
81Embryology — 1 morula, 2 blastula 1 blastula, 2 gastrula with blastopor …
82Egg (biology) — Bird eggs and others (click on image for key) …
83Pregnancy (mammals) — For pregnancy in humans, see pregnancy. A pregnant lioness. In mammals, pregnancy is the period of reproduction during which a female carries one or more live offspring from implantation in the uterus through gestation. It begins when a… …
84Chorionic villi — Diagram of a transverse section, showing the mode of formation of the amnion in the chick. The amniotic folds have nearly united in the middle line. Ectoderm, blue; mesoderm, red; entoderm and notochord, black. (Vill …
85human cardiovascular system — ▪ anatomy Introduction organ system that conveys blood through vessels to and from all parts of the body, carrying nutrients and oxygen to tissues and removing carbon dioxide and other wastes. It is a closed tubular system in which the… …
86muscle — muscleless, adj. muscly, adj. /mus euhl/, n., v., muscled, muscling, adj. n. 1. a tissue composed of cells or fibers, the contraction of which produces movement in the body. 2. an organ, composed of muscle tissue, that contracts to produce a… …
87poison — poisoner, n. poisonless, adj. poisonlessness, n. /poy zeuhn/, n. 1. a substance with an inherent property that tends to destroy life or impair health. 2. something harmful or pernicious, as to happiness or well being: the poison of slander. 3.… …
88Chorion — For the chorion in invertebrate eggs, see Chorion (egg). Chorion Diagram showing earliest observed stage of human embryo …
89Cyst — A closed sac or capsule, usually filled with fluid or semisolid material. * * * 1. A bladder. 2. An abnormal sac containing gas, fluid, or a semisolid material, with a membranous lining. SEE ALSO: pseudocyst. [G. kystis, bladder] adventitious c.… …
90Drosophila embryogenesis — Drosophila embryogenesis, the process by which Drosophila (fruit fly) embryos form, is a favorite model system for geneticists and developmental biologists studying embryogenesis. The small size, short generation time, and large brood size make… …
