Beginning of Life

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Beginning of Life Reproduction is a process through which continuity of life is enabled when organisms give rise to their offspring. Reproduction can be either asexual or sexual. Asexual reproduction results to offspring that are identical to each other and to the parent cell. This is because only one parent is involved and no fusion of gametes occurs. While sexual reproduction occurs when two parents produce gametes that fuse resulting to offspring mostly in multicellular organisms.

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Mitosis is a type of cell division whereby two daughter cells are produced with the exact genetic composition as the parent cells. Whereas meiosis is, a form of cell division that occurs when diploid cells half resulting to haploid cells. Diploid cells have two chromosome pairs each from one of the parent cells from mitotic cell division. Haploid cells have half the number of chromosomes as the parent cell from meiotic cell division.

Fertilization also known as syngamy is the fusion of female and male gametes to form a zygote that develops to a new offspring. A few days after fertilization the mass of cells formed are referred to as blastocyst. Cells on the outer part provide protection for cells on the inside that develop to an embryo after continuous cell division (Ke et al., 2017). Gametes are the reproductive cells responsible for fertilization in sexual production. For fertilization to occur it must involve female and male gametes.

Embryo formation occurs through the rapid cell division of the zygote as it moves through the fallopian tube. The cell division results to the formation of the inner cell mass that develops to an embryo and the trophoblast. The inner cell mass and the trophoblast become a blastocyst that attaches to the uterine wall, a process termed as implantation. During this process, pregnancy hormones elevate to sustain the pregnancy.

Gastrulation then follows for cell differentiation and cell development from a single layered cell to a multicellular structure, a blastocyst. Formation of three cell layers occurs referred to as germ layer; the germ layers are the basis of differentiation to different organ systems. The endoderm, ectoderm and mesoderm are the three germ layers. The ectoderm differentiates into the nervous system and epidermis. The endoderm differentiates into digestive

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system columnar cells and the mesoderm differentiates into connective tissue and body muscles (Ke et al., 2017).

Three weeks after fertilization the formation of the embryo occurs, a development stage after the blastocyst. An embryo has undergone formation of a number of internal body organs and even some external features. For instance, blood vessels, the heart and blood cells, the brain also begin its stages of development at this point (Ke et al., 2017). The embryo’s blood vessels development takes place in the villi as the vessels are connected to the placenta through the umbilical cord. However, the embryo and mother’s blood are separated through a thin layer.

Eight weeks after fertilization, most developmental changes have taken place and the embryo now becomes a fetus.

Life begins at conception immediately the male and female gametes fuse. This is because there is evidence of life once the zygote is formed and developmental stages take place after conception. Differentiation then follows resulting to an offspring.

The Catholic Church supports life from the moment of conception, throughout pregnancy until birth for married couples as procreation is allowed. The Catholic Church healthcare workers aim at reducing infant mortality rates and promote pregnant mothers life. They condone abortion and provide emotional, physical and psychological support to people who have had an abortion trauma. Any procedure that endangers the life of the baby is forbidden (Guiahi, 2018). They not only provide prenatal and postnatal care but also counsel married couples with infertility issues.

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References

Guiahi, M. (2018). Catholic health care and women's health. Obstetrics & Gynecology, 131(3), 534-537.

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Ke, Y., Xu, Y., Chen, X., Feng, S., Liu, Z., Sun, Y., ... & Liu, J. (2017). 3D chromatin structures of mature gametes and structural reprogramming during mammalian embryogenesis. Cell, 170(2), 367-381.