During the first week after conception, the zygote divides and multiplies, going from a one-cell structure to two cells, then four cells, then eight cells, and so on. This process of cell division is called mitosis.
What develops first in prenatal development?
The embryo’s gastrointestinal tract, spinal cord, heart, and brain are the first organs to develop. This starts about one week after conception. The placenta also develops in the embryonic stage and it plays a vital role in pregnancy because it carries nutrients, oxygen, and water to your baby.
What is the most critical stage of prenatal development?
The embryonic period is the most critical period of development because of the formation of internal and external structures.
Which stage of prenatal development is the longest?
In the fetal stage, the developing human organism is called a fetus. This is the longest stage, starting in the ninth week after conception and continuing until birth.
How long is the germinal stage?
The germinal period (about 14 days in length) lasts from conception to implantation of the zygote (fertilized egg) in the lining of the uterus. During this time, the organism begins cell division and growth.
What are 4 environmental factors that can harm a fetus?
Environmental factors which have been implicated in adverse pregnancy outcome include smoking, video display terminals, anesthetic gases, antineoplastic drugs and exposure to lead, selenium and inorganic mercury.
Which is the correct order in which a baby develops?
A baby goes through several stages of development, beginning as a fertilized egg. The egg develops into a blastocyst, an embryo, then a fetus.
What is the last part of a baby to develop?
Just four weeks after conception, the neural tube along your baby’s back is closing. The baby’s brain and spinal cord will develop from the neural tube. The heart and other organs also are starting to form and the heart begins to beat. Structures necessary to the formation of the eyes and ears develop.
What is the importance of prenatal development?
Pre-Pregnancy and prenatal care can help prevent complications and inform women about important steps they can take to protect their infant and ensure a healthy pregnancy. With regular prenatal care women can: Reduce the risk of pregnancy complications.