DEVELOPMENT OF MULTICELLULAR ORGANISM: Process of Development

                   Process Of Development

 

 According to research and observations, scientist affirmed that there are four essential process by which a multicellular organisms is made, which are cell proliferation, cell specialization, cell interaction and cell movement.

Cell proliferation

     

Cell proliferation refers to the process that result in an increase in the number of cells. It is a fundamental process among living organisms that is necessary for general development ( Embryonic development, organ growth and development as well as various physiological process).

    This is the first process in the development of multicellular organisms which involves the growth and division of the cells. Here the cells divides through a process know mitosis ( Somatic cell division) producing two equal copies of themselves. During this process, growth factors signal pathways which serves to activate the cells to enter the cell cycle. This process of cell proliferation is highly regulated to ensure that there is balance between the different types of tissues.

Cell Specialization 

   

Cell specialization is the process that is responsible for the production of cell with different traits at different positions. Cell specialization also known as cell differentiation is the process by which generic cells change into specific cells meant to do certain task within the body. Cell specialization is most important in the development of embryos . This process sees cells ( Embryonic cells) changing from their simple forms into more specialized cells both in structure and function. 

  Cell differentiation is particularly important among multicellular organisms. It can be debated that this process is one of the most important process that sets multicellular organisms from simple ( unicellular) organisms. Why? This is due to the fact that the process result in the transformation of the simple zygote in to a complex organisms with different types of tissues and cells. For example, the heart and blood are both made up of cells, they are made up of various types of cell that specializes to carry out different functions, which ensures the survival of the organisms

  Cells contains different genetic materials ( Genes) which are responsible for cell development, and these genes in the cell are either expressed or repressed allowing a group of cells to differentiate into a specific types of cell for a given function. This is made possible by certain signals inside and outside the body that trigger which genes will be expressed or depressed.

   This phenomenon is an important process that helps the development of different types of cells that serve different functions in the body . As cell differentiate, they change in shape and size depending on their functions with each types of cell carrying out their respective functions and they ensures they are able to support life of the organisms.

Cell- cell interaction

 

 Cell-cell interaction is important for maintaining structural integrity of tissues, polymerization and proliferation of the cells. Cell- cell interaction is important for synchronizing response in groups of cells at the tissue level, forming a communication channel between cells that do not rely on outside signaling. Example of such interaction include the calcium signal passing through gap junctions in cardiac muscle tissue to synchronize beating of cardio myocytes and supra cellular action cables that synchronize cell movement in development.

   Based on the definition, explanation and description by scientist, this process of cell- cell interaction is responsible for co - ordinating the behaviours of respective cells in relation to the neighboring cells. We can also simply put it as the process which includes direct interaction of the surface of the cells, which is essential in both the development and functioning of the organisms.

   This biological interaction ( Communication) between cells is made possible by a number of molecules including peptides, proteins, amino acids and steroids among others. Moreover, this interaction may also occur through the matrix ( fluid between the cell) allowing communication between the cells through signals. However, any given group of cells can only respond to given signals while ignoring others because they have specific cell surface receptors that can only receive and respond to a given signal.

  Furthermore, as there are different types of message and response ( biochemical activities) going on in the body, so also there are different types of cell interaction. They are ; Gap junctions, Tight junctions and desmosomes. These types of junctions have different purpose and are found in different places, but we shall not be discussing vividly on that.

Cell movement

  

This is the last point to be discussed under the topic of the process of development of multicellular organism.

   Cell movement or motility is a highly dynamic phenomenon that is essential to a variety of biological process such as the development of an organism ( morphogenesis) , wound healing, cancer metastasis and immune response. For example, during morphogenesis there is a targeted movement of dividing cells to specific sites to form tissue and origins.

  Cell movement was observed as early as 1675 when van leeuwenhoek saw cells crawl across his microscope slides. However, the molecular mechanism behind cell movement have become a scientific focus only in the past few decades.

  Moreover, in a more understandable from, we can describe cell movement as the process through which the cells are re - arranged so as to form the necessary tissues and organs. During Embryonic development, cell go through a complex process of events that leads to their respective shape and positioning in the formation of all the essential tissue and organs in Multicellular cellular organisms. However, this process occurs once the cell start receiving signals that influence a complex and well coordinated mechanism that moves the cells in the right direction to the intended destination.