Question

how does a single-celled fertilized egg grow into an adult human body?

Answer 1

Answer:

Fertilized egg i.e the zygote divides and redivides into a ball of cells. The zygote grows by cell division and produces an embryo. Fixing the embryo to the uterus is called implantation.

Answer 2

SINGLE-CELLED FERTILIZED EGG

In human and most other Anisogamous organisms, a zygote is formed when an egg cell is fertilized by a sperm cell. In single-celled organisms , the zygote can divided asexually by mitosis to produce identical offspring.

EXPALNATION

• Fertilized egg i.e., the zygote divides are re divides into a ball of cells. The zygote grows by cells divisions and produces embryo. Fixing the embryo to the uterus is called implantation.
• This is a kind of embryo and it reaches the uterus and gets attached to the wall of uterus. The embryo undergoes a process "specialization" of cells.
• In the embryonic development of humans and other animals, the zygote stage is brief and is followed by cleavage, when the single cell becomes subdivided into a smaller cells.