Blastocyst: Implantation is one of

Implantation is one of the stage of pregnancy. During this stage, the blastocyst attaches to the wall of the uterus on uterine endometrium. The developing embryo receives oxygen and nutrients from the mother from this attachement. Implantation is controlled by trophoblast and occurs by decidual cell reaction. Both the morula and blastocyst refer to the earliest stages of an embryo. After 3–4 days of the egg being inseminated the embryo cells assume a spherical shape. This transition is known as the morula. After 4–5 days, a cavity forms within the embryo cells. This stage is known as the blastocyst . Further, cells within the blastocyst are known as the inner cell mass and is the initial stage in giving rise to the head and body of the developing fetus. Implantation is initiated, when the blastocyst comes into contact with the uterine wall. The blastocyst is a structure formed in the early development of mammals. It possesses an inner cell mass, which subsequently forms the embryo. The outer layer of the blastocyst consists of cells collectively called the trophoblast. This layer surrounds the inner cell mass and a fluid-filled cavity known as the blastocoele. The trophoblast gives rise to the placenta. In humans, blastocyst formation ... Identify the human development stage shown, as well as the related right place of its occurrence in a normal pregnant women and select the right option for the two together. Development stage - blastula; Site of occurence - end part of fallopian tube Development stage - blastocyst ; Site of occurrence - uterine wall Development stage - 8-celled morula; Site of occurrence - starting point of fallopian tube Development stage - late morula; Site of occurrence - middle part of fallopian tube