Do they make things into partner-gods which cannot create anything and are themselves created; which are not capable of helping them and cannot even help themselves?
(Qur'an, 7: 191-192)
On the eighth day, the cells begin to differentiate and they arrange themselves into two distinct groupings, an inner and an outer one. The inner cell mass (embryoblast), forms the cells that the embryo will possess throughout its whole life. The outer group of cells (trophoblast), is composed of the cells that assist the human being in its life in the mother's womb, that is, for nine months until its birth.
The inner cell mass separates itself from the outer group of cells that will serve it throughout the nine months. The remaining region will become the umbilical cord providing the connection between the embryo and the placenta that will develop later. At about the same time that the placenta begins to form, the inner cell mass flattens and develops into three layers of cells in what is called the "embryonic disc".
The three types of cell layers are the ectoderm, the mesoderm, and the endoderm. In a process called differentiation, cells from each layer move to certain areas of the embryonic disc and then fold over to form tubes or clusters. These tubes and clusters develop into various tissues and organs of the body.27
Cells from the outermost layer, the ectoderm, form the brain, spinal cord, the sense organs and the lens of the eye. Moreover, this layer will form the epidermis, the sweat glands, tooth enamel, hair and nails. The innermost layer of the embryo (the endoderm) will cause the development of the organs that compose the digestive and respiratory systems (liver, lungs, pancreas, etc.) and the related glands (thyroid, thymus, etc.). The third layer (the mesoderm) is formed between these two layers. From this layer are formed the heart, muscles, bones, tendons, kidneys, glands, blood vessels, and reproductive organs. The lymphatic vessels and the epithelia (surface, or lining, tissues) which cover the most internal and external surfaces of the body and its organs also develop from this layer. The cells which compose all the tissues of the body are formed from these stem cells which develop from one of these layers.
It is very important to think about the meaning of the last sentence of the above paragraph, and to consider well the significance of what it says, because only in this way can we begin to conceive of the extraordinary development of a human being. The fact that all the elements that constitute the human body (organs, tissues, systems, blood vessels, blood, etc.) develop from the three kinds of layers that make up the embryo will lead a thinking person to find the answer to the question: Where does this supreme intelligence that the cells possess come from?
In the meantime, there are some details that we must not lose sight of and that make these changes even more extraordinary. For example, in the course of the development of a human being, there is a perfect harmony among these three layers of cells. In order for the approximately 200 kinds of cells in the body to be produced from three kinds of cells, a definite sequence and timing is required. For example, the sequence of events in the differentiation of the blood cells and the skin cells is very different in each case. This is a remarkable phenomenon which raises a number of questions.
Changes in the uterus begin with fertilisation and it becomes a place where the baby will spend nine months in security and comfort. The uterus increases in size and provides a protective shelter for the embryo. All the preparations are made by cells in the uterus. There is only one explanation for the fact that these cells are aware of what another cell needs, that is, these cells move according to the inspiration of Almighty God.