Which sequence correctly depicts the development of offspring?
zygote ® fetus ® embryo ® blastocyst
blastocyst ® embryo ® fetus ® zygote
fetus ® embryo ® blastocyst ® zygote
zygote ® blastocyst ® embryo ® fetus

The right answer is zygote ® blastocyst ® embryo ® fetus.

When a spermatozoon (sperm) joins the egg in one of the fallopian tubes, fertilization occurs; then begins cell division. The fertilized egg, or zygote, is transformed into a cellular mass called morula that goes down to the uterus. The zygote divides into two cells in two to three hours. After 5 days, it reaches about 90 cells. The division is continued until a blastocyst forms, a hollow mass consisting of a hundred cells.

A layer will cover it, called trophoblast, and begin to invade the uterine lining and form cords that attach the blastocyst to the lining of the uterus. The trophoblast will turn into a placenta, which is used to feed the embryo. Formed at the same time as the placenta, the umbilical cord connects the zygote to this one. At this point, the baby is called an embryo. It will be a fetus as soon as the organs have begun to develop.

[ answer ]

foliated

[ explanation ]

foliation forms in a rock when pressure squeezes the rock together. the rock then has a design of many different color little lines. there are three types of foliated rock. the types are slate, schist, and gneiss. each type of foliated rock is different based on grain size and foliation characteristics. the lines appear when the rock has been under pressure.

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my teacher would say no s