The Importance Of Human Fertilization

Although life is a continuous process, fertilization is a critical landmark as under ordinary circumstances, a new, genetically distinct human organism is thereby formed (O’Rahilly, Ronan & Muller, 1996). The development of a human being begins with the process of fertilization where two highly specialized cells, the spermatozoon from the male and the oocyte from female, unites to give rise to a new organism or new life, the zygote (Langman, 1975). Fertilization is also called as conception. Embryology textbooks are clear about when life begins as stated by Moore and Persaude (2003):

Human prenatal development is a continuous process that begins with an oocyte (ovum) from a female is fertilized by a sperm (spermatozoon) from a male. Cell division,

This stage takes place from the end of the embryonic period which is from the end of eight weeks until the time of birth (Papalia, Olds & Feldman, 2009). It is the longest stage out of all three stages. The appearance of the first bone cells signals the beginning of the fetal stage. The first part of the embryo to develop is the neural tube. This will then become the spinal cord and brain structure. The most notable development during this stage is the increased differentiation of body parts and greatly enlarged body size. The length of fetus increases until normal body proportion is achieved and all internal systems and organs continue to increase their efficiency. At this stage, organs and body systems become more complex and final details such as fingernails, toenails, and eyelid developed (Papalia, Olds & Feldman, 2009). The outline of fetus and fetal movement can be observed through the use of high frequency sound waves which is the ultrasound. Individual differences between male and female fetuses are shown from the movements, heart rates and activity level of foetuses (Papalia, Olds & Feldman, 2009). For instance, male fetuses are generally more active and move more vigorously than female fetuses throughout the gestation regardless of their size which suggests that the tendency of activeness is formed inborn (DiPietro, Hodgson, Costigan, Hilton, & Johnson, 1996). Quickening also occur at this stage where the mother feels movement of the fetus for the first time. The five senses of fetus also start to work though they are still in the mother’s womb. This indicates that some senses are developed inborn, right before