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>
A) toward the earth ...hope this hlep
Plant-like protists produce almost one-half of the oxygen on the planet through photosynthesis. Other protists decompose and recycle nutrients that humans need to live. ... Humans use protists for many other reasons: Many protists are also commonly used in medical research