Sex cells are haploid, therefore it has half the number of chromosomes (23) while other cells have 46
write it in your own words:
"In humans, five days after the fertilization, the blastocyst performs zona hatching; the zona pellucida degenerates and decomposes, to be replaced by the underlying layer of trophoblastic cells. The zona pellucida is essential for oocyte growth and fertilization."
The zona pellucida supports communication between oocytes and follicle cells during oogenesis; protects oocytes, eggs, and embryos during development, and regulates interactions between ovulated eggs and free-swimming sperm during and following fertilization.
Compaction and cementation
Answer:
The researcher would choose the "Prospective study" design.
Explanation:
A prospective unit study is a longitudinal unit learning that trails over time a collection of alike persons who vary with admiration to convinced issues under learning, to govern how these issues disturb charges of a convinced consequence. The prospective study in the exploration depicts a prospective study that watches for outcomes, such as the development of a disease, during the study period and relates this to other factors such as suspected risk or protection factor(s). The study usually involves taking a cohort of subjects and watching them over a long period.
I think at 15 days because that is when it goes down
