Ablastocyst is a group of cells that forms after a human egg is fertilized. the blastocyst consist of two types of cells. some of these cells develop into all of the cells of a growing fetus. what do the other cells develop into?
a. the umbilical cord
b. the placenta
c. the embryo
d. the fetus

What is a group of organisms that are closely related and share similar characteristics

Australopithecus robustus was likely the longest-surviving species of australopithecine in south africa. it had: a. large molars, a big face, and a sagittal crest. b. a large body, large teeth, and a sagittal crest. c. a big brain, big teeth, and a big face. d. a big face, large teeth, and a large body

The table below shows the elements that mainly comprise each of the four layers of earth: elements in layers layer main elements crust oxygen, silicon mantle iron, magnesium outer core iron, nickel inner core iron which of these elements make up the layer that is 0.2 to 1.1 percent of earth's total diameter?