The process of human development begins with the formation of a zygote. A zygote is formed when a sperm cell fertilizes an egg cell during sexual reproduction. This results in a single cell with the full genetic material of both parents.
The genetic content of the zygote is unique, as it contains a combination of genetic material from both parents. It differs from the genetic material found in the body cells of the parents because it undergoes a process of recombination during fertilization, which results in a new combination of genes in the zygote.
One developmental process involved in the change from a zygote into an embryo is cell division. The zygote undergoes several rounds of mitosis, where it divides into smaller and smaller cells. This process is essential for the formation of the embryo, which eventually develops into a fully formed human.
Fetal development usually occurs in the uterus, a muscular organ in the female reproductive system. The uterus provides a protective environment for the developing fetus, supplying it with nutrients and oxygen through the placenta.
Two factors that can affect fetal development are maternal nutrition and exposure to harmful substances. Maternal nutrition plays a critical role in fetal development, as a lack of essential nutrients can lead to developmental abnormalities. Exposure to harmful substances, such as drugs and alcohol, can also have a significant impact on fetal development, leading to physical and cognitive impairments. It is essential to ensure proper maternal nutrition and avoid exposure to harmful substances during pregnancy to promote healthy fetal development.