Scientific principle two: cell division

 

All organisms have the capacity for growth and reproduction; this is what allows an organism to pass through the stages of life with the ultimate goal of producing more offspring. These vital principles of life are driven by the cellular processes of meiosis and mitosis.

 

Meiosis is a process which divides a parent cell into 4 separate daughter cells each carrying half as much genetic information as the original parent cell. These daughter cells are called gametes which are sex cells that carry genetic information for sexual reproduction. They come in two forms of both the sperm cell in males and the egg cell in females. During sexual reproduction the genetically modified egg cell carrying its half of the total genetic information defined by the haploid number and sperm cell carrying the other half of the total genetic information or haploid number combine to code for the offspring with a full set of genetic information defined by the diploid number. Thus the now fertilised egg cells called zygote contains the diploid number or full set of genetic information which includes the transgene carried by the egg cell. This particular zygote is the ultimate result of genetic modification and act as a template for all future body cells created through the process of mitosis. (Sarbinowski 2015)

 

The fertilised egg becomes a unicellular zygote, which is a fertilised egg, containing the transgene and act as a template for all future replications and thus the animal itself. The zygote undergoes the process of mitosis and cytokinesis in order to replicate. Mitosis is a cellular process which divides a cell into many identical daughter cells, however unlike meiosis; mitosis produces two identical daughter cells with the same amount or diploid number of chromosomes (genetic information is contained within chromosomes). (Arena 2014)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Mitosis is a process which divides the nucleus of a cell. Since all genetic information is contained within the nucleus of a cell the process of mitosis is the most pivotal process in replication of the cell and is the process in which the transgene is also replicated. If no mutation occurs mitosis copies and creates identical replications of the genetic information for the daughter cells which will turn out as exact copies of the parent cell due to uniform instructions. Hence this is what allows the transgene contained in the parent cell or zygote to be copied into the daughter cells, thus the daughter cells will exhibit the same desired traits inserted into the parent cell. The stages of mitosis are as follows.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

While mitosis splits the nucleus or "brain" of a cell which contains all genetic information, the process of cytokinesis actually spilt the cytoplasm or "body" of a cell which carries out its functions and contains the nucleus. (Nature Education 2014) Cytokinesis splits the cell so that so that one nucleus ends up in each daughter cell. Through the process of mitosis and cytokinesis the unicellular zygote has now divided into two separate cells, forming an embryo. The process of mitosis and cytokinesis are constantly functioning and new cells are constantly being produced, meanwhile the transgene is also duplicated into every new cell.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Finally the embryo containing the cells carrying the transgene is transferred into the uterus of a surrogate mother to develop further into an offspring with the traits of the transgene with pharmaceutical value. The animal can now be used as a genetic factory as its milk containing the transgene with pharmaceutical value can now be collected without harm to the animal as it is constantly being produced due to mitosis.

 

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