Реферат на тему Baby Paper Essay Research Paper Normally when
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Baby Paper Essay, Research Paper
Normally, when a baby is born approximately nine months after being conceived, he or she has all the features of its parents. It is fully developed for life separate from its mother?s umbilical cord. It is fascinating how they are formed inside the womb. Beginning from day one, life has started. Embyonic development is a complex process involving cell division, cell differeniation, and cell movement, as the genetic information from the parents are passed down to this new life (Arms 582).
The first of the three major aspects of development is differentiation into cell types. From one fertilized zygote, which is one type of cell, other cells like liver and skin cells are formed. These cells differ from one another in that they have synthesized different enzymes and structural proteins (Arms 582). This must be due to the fact that genes have become active in different cells during development.
The second aspect is growth. At varios stages, food from outside the baby reaches the embryo and enables it to increase its overall size. This nourishment comes from the mother?s placenta. Connecting the baby to the palcenta is the umbilical cord. Before this point however, mitosis has happened many, many times, enabling the baby to encrease in size.
The third aspect of embyonic development is the formation of shape. This consists of the rearrangement of proteins and other molecules to form larger structures within cells and, most importantly the movement and buliding of cells into specific patterns to form organs. There is much debate as to exactly how these particular shapes of organs actually happens.
Although many scientists argue and speculate over the reasons behind the exact formation of a baby, all scientists will agree that embryonic development can be divided into four main stages. They are cleavage, gastrulation, neuralation, and oraganogenesis.(leibling 5) Each stage is a miracle in itself and one would be amazed at what exactly goes on in a mother?s womb. I have decided to make a clay model of what a baby looks like early on in its embryonic development and to show it in a simulated womb made out of gelatin in a fish bowl.
Annotated Bibliography
Arms, Karen. Biology of Life. Philadelphia: Saunders Publishing House, 1982.
Leibling, Maryanne. How did I get here, Mommy? New York: Dryden Publishing, 1991.
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