Fertilized egg (also called zygote) reaches uterus, particularly at blastocyst stage (approximately 5 to 6 days post fertilization) and gets adhered to the uterine wall and from now it is considered as embryo. This process is known as implantation.
During the stage of prenatal development, the growing embryo receives nutrients and oxygen from the mother through placenta and develops into fetus (8th week post fetilization, which is 10th week of pregnancy). Fetus grows within uterus till the last week of pregnancy that is around 38 weeks.
Thus, uterus is the right answer for the given blank.
A fertilized egg usually implants itself and develops in the uterus. <span>During the prenatal development, fertilized egg adheres to the wall of the uterus. Zygote (fertilized egg) at this stage forms blastocyst. The blastocyst consists of an inner cell mass and the outer layer -the trophoblast. Trophoblast surrounds the inner cell mass and a fluid-filled cavity - blastocoele. Inner cell mass will form embryo and trophoblast gives rise to the placenta.</span>
The presence of fins in both species represents an adaptation to the same environment (i.e., sea), but in no way does this adaptation means close evolutionary homology between fishes and mammal cetaceans (whales)
This scenario has been discovered and studied in slime molds.
Explanation:
The green beard effect is one of the three fundamental mechanisms of kin selection. In the 1960s, W.D. Hamilton in his work on the evolution of altruism brought it into the highlight. The other two mechanisms are kin discrimination and population viscosity. Green-beard effect functions even when the altruist and her recipients are not genealogical kin.
