AP BIOLOGY

Detailed explanation-1: -While the zygote is passing through the fallopian tube, it undergoes cleavage, a process of rapid mitotic divisions that result in the formation of progressively smaller cells. These smaller cells, called blastomeres, are totipotent (capable of forming a complete embryo).

Detailed explanation-2: -First, the zygote becomes a solid ball of cells. Then it becomes a hollow ball of cells called a blastocyst. Inside the uterus, the blastocyst implants in the wall of the uterus, where it develops into an embryo attached to a placenta and surrounded by fluid-filled membranes.

Detailed explanation-3: -During fertilization, the sperm and egg unite in one of the fallopian tubes to form a zygote. Then the zygote travels down the fallopian tube, where it becomes a morula. Once it reaches the uterus, the morula becomes a blastocyst. The blastocyst then burrows into the uterine lining-a process called implantation.

Detailed explanation-4: -The zygote divides into two cells by mitosis. Then, these cells each divide by mitosis. This process repeats many times to produce the cells in an embryo which develops into a baby.

Detailed explanation-5: -The fertilized cell is a zygote. The zygote undergoes mitosis to form two identical cells that remain attached. This takes place about 36 hours after fertilization. Mitosis then occurs more frequently.