AP PSYCHOLOGY

Detailed explanation-1: -The zygote is a single diploid cell, which will ultimately multiply through mitotic division to form a multicellular embryo. This mitotic division does not result in any significant growth and the multicellular cluster that is formed is the same size as the zygote. This cell division process is referred to as cleavage.

Detailed explanation-2: -During cleavage, the cells divide without an increase in mass; that is, one large single-celled zygote divides into multiple smaller cells. Each cell within the blastula is called a blastomere. Cleavage can take place in two ways: holoblastic (total) cleavage or meroblastic (partial) cleavage.

Detailed explanation-3: -After fertilization, the development of a multicellular organism proceeds by a process called cleavage, a series of mitotic divisions whereby the enormous volume of egg cytoplasm is divided into numerous smaller, nucleated cells. These cleavage-stage cells are called blastomeres.

Detailed explanation-4: -During cleavage, the cells divide without an increase in size (without growing); so the large single-celled zygote divides into smaller and smaller cells called blastomeres. After the cleavage has produced over 100 blastomeres, the embryo is called a blastula.

Detailed explanation-5: -The single-cell embryo is called a zygote. Over the course of the next seven days, the human embryo undergoes multiple cell divisions in a process called mitosis.