Exploring Cell Biology: Specialized Tissue Generation

Introduction

Cell biology involves studying the structural and functional features of the cell and it revolves around the perception that the cell acts as the fundamental unit of life. The cell allows detailed understanding of the composition of the organism as they create body structure and contains hereditary material required for various differentiation in the body (Pittenger et al., 2019). Thus, the way generation of specialised tissues occurs from the embryonic stem cell in an individual is to be discussed. Moreover, different between normal and cancer cell are to be compared and contrasted.

Generation of specialised tissue from embryonic stem cell

A stem cell is referred to unspecialised cell which has the ability to divide without any limit and under special condition shows ability to differentiate into specialised cells. The first embryonic stem cell is developed from the division of the zygote and they are mentioned as totipotent. This is because the first embryonic stem cell shows the potential of differentiation into cells required by the organism to develop and grow initially. The embryonic cells which are developed from the totipotent cells act as precursor to form the fundamental layer of tissue of the embryo and are known as pluripotent cells (Takata et al., 2017). The pluripotent cell has the ability to develop into any type of human tissue through differentiation but are unable to support the entire development of the organism (Zakrzewski et al., 2019).

The pluripotent cells later become slightly specialised and are known as multipotent cells which shows the ability to differentiate into various cells within a certain cell lineage or small number of lineages like red or white blood cells (Chen et al., 2019). The multipotent cells are able to form further specialisation after development into specialised oligopotent cells that is limited to become few limited numbers of cells or tissue. For example, ES cells are gathered from the initial cell division that later forms into blastomere through repeated division which still contains undifferentiated cells (totipotent). The outer cellular layer of blastomere after five days differentiate to form placental tissue (multipotent cells). The Inner Cellular Mass (ICM) after separation from the embryonic environment become multipotent and later into oligopotent cells as it direct formation of specified cell with gradual differentiation (Sozen et al., 2018).

The transcription factors act as single class of protein which binds specifically to gene on the DNA molecule and acts to either inhibit or promote the transcription process. The primary mechanism in the ES cells which indicates which genes in the cells are to be expressed and which are to be suppressed for it to be specialised into different tissue is dependent on the use of different transcription factor proteins in the body that binds with specific DNA and enhances or hinder the transcription regarding different genes (Manley et al., 2017). Thus, the through expression of the transcription factors determines which cells are to be specialised in which one from the hundred different types of cells in the body to form specialised tissue. The transcription factors like OCT4, SOX2 and NANOG are the 3 key basic transcription factors which are expressed in embryonic stem cells. The following transcription factors are seen to play critical role to maintain the self-renewal and pluripotency characteristics of the stem cells (van Schaijik et al., 2018).

Comparing and contrasting the differences between normal and cancer cells

On comparing and contrasting, the normal cells are seen to stop reproducing or growing when enough healthy cells are present in the body. In contrast, cancer cells show inability to stop growing irrespective of the need in the body and due to their continued growth tumour is formed which is the cluster of outgrown cells (Kalyanaraman, 2017). The cancer cells mainly developed due to mutation in the genetic composition of the cells and thus they are found to show hindered cell communication (Ramanujam et al., 2019). However, the normal cells have well-developed cell signalling receival process and they act according to the signal received (Kalyanaraman, 2017). The normal cells show the capability to either die or get repaired when they are old or get damaged (Kalyanaraman, 2017). However, the cancer cells show no capability to repair or die as the p53 gene which a tumour suppressor gene responsible for checking the cell growth is damaged (White et al., 2017). The normal cells do not show metastasizing ability and they remain localised in specific area of the body (Kalyanaraman, 2017). However, the cancer cells show metastazising ability due to their lack of adhesion capability and lead to infect other parts of the body (White et al., 2017).

The cellular structure of the cancer cells shows that it has irregular and darker nucleus compared to the normal cells due to excess present of DNA and shows abnormal number of chromosomes to be present in the cell in disorganised way (White et al., 2017). However, in normal cells the nucleus is normally structured, and the chromosomes are organised in a normal fashion (Kalyanaraman, 2017). The normal cells usually show the ability to divide 50-60 times after which it develops apoptosis (Kalyanaraman, 2017). However, the cancer cells show no specific rate of differentiation and divide in uncontrolled way (White et al., 2017). The normal cell after getting damaged are identified and removed through apoptosis by the immune system (Kalyanaraman, 2017). However, the cancer cells show the ability to mimic the immune system due to which their uncontrolled growth remain undetected leading them to form tumour (White et al., 2017). The cancer cells produce their required energy through glycolysis irrespective of the presence of oxygen (White et al., 2017). However, the normal cells develop most of their energy through the Krebs cycle and a small amount of energy through glycolysis where oxygen is deficient (Kalyanaraman, 2017). In case of normal cells, they have definitive length of telomere which gets shortened with each division and gradually leads the normal cell to die after certain division (Kalyanaraman, 2017). However, in case of cancer cells, the telomere length gets extended due to which they continue to divide without any control (White et al., 2017).

Conclusion

The above discussion mentions that embryonic stem cells develops from the undifferentiated cell ma of the human embryo. It gets differentiated into totipotent, pluripotent and multipotent cells to gradually get developed into specified cells in the body. The transcription factor are mainly responsible in gradually and directed differentiation of the embryonic stem cells into specialised cells. The normal and cancer cells differ in respect of growth, communication, cell repair ability, stickiness, ability to metastasize, appearance and others.

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References

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