The branch of science that deals with plants and animals is known as Biology and the sub branch which deals with the cell structure and their functionalities is known as Cellular Biology. Both structure and function are equally important and one cannot be given precedence over the other. One of the most important aspects that need to be taken care of while studying cellular biology is to stick to precision as errors of any sort may lead to dire consequences.
To study these minute elements, the biomedical engineers make use of advanced equipments like microscopes (process is called microscopy). With the help of these powerful magnifiers, scientists are able to see study their structure and by looking at the different activities, able to determine the exact way of functioning. It does not need to be explained as to why such equipments are required. The naked eye of the humans is not capable of seeing the cells, let alone understanding what is inside them.
Structure: Structure of the cells is formed by proteins. They form the cytoskeleton which is responsible for providing the basic protective covering inside which, all the components of the cell are present. Cells are made of multiple organelles like the Mitochondria, Nucleus, Golgi Bodies etc. While one acts like the power house, others indulge in control and storage activities. The outer covering is known as the cell membrane which protects it from any outside matter and allows for diffusion of materials inside and outside the body. Because they are the outer walls, they also provide the cell with a characteristic shape which at times may also be helpful in identifying the cell type.
Function: Again, proteins play a very important role when the cell functions are in question. These protein molecules perform the basic functions and fuel the others to do the same. On the other hand, it is the genes which fuel the proteins (more than 20,000 different types of proteins are under their control). The outer layers of all the tissues, (groups of similar cells working together) are bound together with the help of proteins.
The genetic information carriers, DNA (Deoxyribos Nucleic Acid) is made up of 4 components, Adenine, Thymine, Guanine and Cytosine. The double helical structure by which it is mostly known is formed by the pairing of the Adenine with Thymine and Guanine with Cytosine. They are part of the chromosomes and are present in the nucleus of the cells. When an organism reproduces, these are transferred from the parents to the child and hence, similar traits can be seen (ever seen a family where parents and children share some features? This is the reason behind it). When the cells replicate or divide, the DNA elements get divided between the two.
Basic functions of the cell include taking part in the metabolic activities that take place in the body. Everything from respiration to digestion, immune system to the circulatory system is being taken care of by some or the other type of cell.