Images: [3]
Every human body has billions of microscopic units called cells. Cells carry out numerous of chemical reactions and processes that make up the essence of life. The structure of cells varies in size and shape and has different functions. There are four main features with in a cell and these consist of the cell membrane also known as the plasma, the cell nucleus which contains mature red blood cells, the cytoplasm and the organelles which is a "various component of a cell with a distinct structure and their own functions and can be likened to miniature organs. Organelles include mitochondria, the endoplasmic reticulum the Golgi apparatus and lysosomes" [1]
The nucleus is usually the largest structure inside the cell which contains chromosomes which contains deoxyribonucleic acid (DNA), this is the genetic coding material which determines difference characteristics. The nucleus main function is to contain instructions for growth, work and maintenance of the cell, it controls nearly all the activities of the cell.
"A smaller, darker sphere is often visible, the nucleolus, this is a source of ribonucleic acid (RNA) one of the nucleic acids" [2]. When a cell is not dividing (known as resting) this is called the chromatin network and the nuclear material appears like a thick, triangle mass. When a cell is in the process of dividing, the chromatin network separates into distinct black threads known as chromosomes and there are 23 pairs of chromosomes in a human cell.
"The nuclear membrane is made up of 2layers, each composed of a lipid bilayer. It has holes all over which are called nuclear pores, to facilitate and regulate the exchange of materials, for example, proteins and RNA, between the nucleus and