Anatomy Which of the following events is involved in cleavage of the zygote during week 1 of development? A A series of meiotic divisions forming blastomeres B Production of highly differentiated blastomeres C An increased cytoplasmic content of blastomeres D A decrease in size of blastomeres 💡 Explanation Which of the following events is involved in cleavage of the zygote during week 1 of development? ✓ Correct Answer: D. A decrease in size of blastomeres