Summary of Part Four
The Church openly states its commitment to the protection of the sanctity of human life and therefore advocates against the use of any type of contraceptives. Essentially, the defense of the Church extends to the unborn, as well as to women during and after pregnancy. The Church recognizes marriage as an act by which the husband and the wife show their love to God and cooperate together to create new life (United States Conference, 2018). The utilization of contraceptives is against the concept of the inseparable bond between the two meanings of a marital act, namely, unitive and procreative. Moreover, according to the Church, the use of certain reproductive technologies is not consistent with human dignity. Therefore, only the reproductive assistance which does not violate the bond between the unitive and procreative ends of the marital act and does not substitute it can be approved. The Church also does not permit experiments done on a living embryo, abortion of the fetus, and surrogate motherhood. The Catholic medical institutions must provide prenatal, obstetric, and postnatal services to women, as well as technical assistance to infertile couples and counseling.
Explanations of Concepts
Asexual – Sexual Reproduction
Asexual reproduction constitutes a form of reproduction which does not imply a combination of gametes or the growth in the number of chromosomes. Sexual reproduction involves the fusion of gametes such as the sperm and the egg.
Mitosis – Meiosis
Mitosis is the process of the division of one cell, which produces two diploid cells and occurs in all organisms, apart from viruses. Meiosis is the process involving two successive cell divisions resulting in four haploid cells and occurring only in fungi, animals, and plants.
Diploid – Haploid
Diploid cells reproduce using mitosis and contain two complete sets of chromosomes, while haploid cells result from meiosis and contain only one complete set of chromosomes.
Gametes
Gametes are special reproductive cells which contain only one set of chromosomes since they are haploid; for instance, female gametes are egg cells, while the male ones are sperm.
Fertilization
Fertilization constitutes a process involving the fusion of male gamete and female gametes, which results in the creation of a zygote.
Zygote
The zygote is the product of fertilization which is also called a fertilized egg, a new cell which gets formed as a result of the fusion of the male and female gametes.
Syngamy
Syngamy is the process of the combining of two cells which leads to the emergence of a cell containing twice the number of chromosomes. Essentially, syngamy is a synonym for fertilization.
Blastocyst
Blastocyst constitutes a stage in embryo development which occurs when the fertilized egg enters the second phase of its growth. Blastocyst occurs from day 5 to day 9 after fertilization.
Implantation
Implantation refers to the process involving the developing embryo, moving through the uterus as a blastocyst contacting with the uterine wall and attaching to it until birth.
Gastrulation
Gastrulation is the process in which the one-dimensional layer embryo turns into of blastula and then reorganizes into the multidimensional and multilayered gastrula.
Embryo – Fetus
The embryo is the human during the early stage of development which involves the formation of the body. An embryo becomes termed a fetus at the end of the 10th week of pregnancy.
Fertilization Process from Cellular Level to Fetus
During sexual intercourse, sperm flows to the oocyte, the egg cell, which leads to the combining of the genetic information combines of the two gametes. The chromosomes from the sperm and the egg pair and form the zygote, a 46-chromosome cell, which then begins to divide and multiply, becoming a blastocyst (Derrickson, 2019). The zygote then arrives at the uterus as a blastocyst and implants itself into the uterine lining. After 15 days, the cells which will in the future form the embryo become an embryonic disc. Others cells form the first elements of the digestive tract, placenta, and umbilical cord. On the 15th day, the embryonic period begins, which involves the embryo containing the mesoderm, the endoderm, and the ectoderm, tissues which them contribute to the formation of the human body (Derrickson, 2019). By the 4th week, the embryo will have a head and a beating heart, while during the next 6 weeks, the embryo receives eyes, limbs, and brain regions. At the end of the 10th week, the embryo becomes a fetus. The fetus continues to grow as its body systems develop as well as muscles, skin, and facial features.
When Does Human Life Begin
Although the beginning of human life is a controversial issue and often can be viewed as a philosophical matter, the research shows that life begins at the moment of conception. According to Barresi and Gilbert (2019), conception constitutes the stage when any type of organism, including a human, starts to develop. Therefore, it is possible to state that conception is the first landmark in the development of any human being and, therefore, the start of their life. As outlined by Singh (2016), life takes place in the human body once the fusion of two unique and complementary cells, the oocyte and the spermatozoon, occurs. Essentially, researchers openly support the idea that life begins at the moment of conception, dispelling the notion that life only starts after the formation of the embryo, the fetus, or the brain.
References
Barresi, M.J., & Gilbert, S.F. (2019). Developmental biology (12th ed.). Sinauer Associates.
Derrickson, B. (2019). Human physiology. Wiley Global Education.
Singh, K. (2016). Integrated approach to obstetrics and gynaecology. World Scientific.
United States Conference of Catholic Bishops. (2018). Ethical and religious directives for Catholic health care services (6th ed.). Web.