The intricate details of life begin with a single cell that develops into a full term fetus within approximately 38-40 weeks. The prenatal development stages outline the growth of the child and give a clearer picture of the development of the child in the womb. The course of this prenatal development is divided into three main periods: germinal, embryonic, and fetal.
The germinal/conception stage begins with conception, occurs within the first 2 weeks. This journey begins when the sperm and egg cell unite in one of the two fallopian tubes. The fertilized egg, known as a zygote, then moves toward the uterus, a journey that can take up to a week to complete. Cell division begins and continues rapidly forming a blastocyst. Finally, the blastocyst arrives at the uterus and attached to the uterine wall, a process known as implantation. The conception stage is basically the preparatory and preliminary process of prenatal development that readies and prepares the body for the impending pregnancy.
Once implantation has occur the the blastocyst is develops into an embryo. This second stage, the embryonic period occurs 2-8 weeks after conception. This is referred as the most important stage of prenatal devllopment as the foundational development of the embryo begins here. During this period, the rate of cell division increases, support systems for the cells form, and organs appear. The mass of cells attached to the uterine wall forms two layers and is now called the embryo. The inner layer of cells of the embryo is the endoderm which develops into digestive and respiratory systems. The ectoderm which is the outer layer of cells will become the nervous system and sensory receptors such as ears, nose, and eyes, and skin. The middle layer known as the mesoderm will develop into the circulatory system, bones, muscle, excretory system, and reproductive system. By the 8th week teeth and intestines start the form as well. From the 11th week onwards, the child is called a...
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