Biology as we all know has been defined as ‘’ the branch of science which deals with the study of life, living organisms and non-living organisms. This definition might seem too straightforward and simple but if does not totally entails the precise definition to the study of life. However, more doors are opened as to the real meaning of life and what does it mean to be alive.

We can all hear a dog when it barks meaning it’s alive. You are alive and so am I. The chair we sit on is not alive neither are our phones alive. The parts of a table that was once made out of wood was alive but the table isn’t alive, so if we burnt the wood and the table in the fire, they aren’t alive either.
What is that precise definition of life? How can we tell if something is really alive and the other dead? Most people have different views as to what being alive means. However, it will be difficult to define what life means exactly. For this reasons, life’s been defined by scientists according to their own perspectives based on living and non- living things but none of these definitions have been proved useful in defining what life really is. To really define life, we must adequately bring a balance between the definitions of both living and non-living things.

Biologist have observed and identified various characteristic traits available to all living organisms as we all know of today. Only living organisms display these characteristics although some non-living organisms have been proved to display some of the characteristics of living organisms.

Living organisms have been proved to be truly organized. Living organisms are all made up of one or more cells which are fundamental to its existence and life. These cells in their individuality performs highly complex biochemical reactions and processes which maintains both its structure and function making each cell highly organized.
Unicellular organisms are organisms which consists of only one cell, while multi cellular organisms are organisms which are made up of more than one cell such as humans. These cells in multi cellular organisms are specialized to perform different functions. They are also organized into Tissues which makes up the Organs which are been needed by the organs to carry out specific functions which the organism would need as a whole.

Life depends on various complex metabolic reactions to keep us alive. These complex metabolic reactions makes it possible for the organisms to work, reproduce, grow, feed and also maintain the organisms’ body structure. Living things uses energy and therefore consume nutrients which makes it possible for the organism to carry out its complex biochemical reactions. These complex biochemical reactions can be called Metabolism.
Metabolism is usually subdivided into Catabolism and Anabolism. In anabolic organisms, complex molecules are made from simpler ones while in catabolic organisms, reverse is usually the case. Anabolic organisms consume energy in their process while in catabolic organisms, they make stored energy available.

Homeostasis is the process by which living organisms regulate its internal environment to maintain the conditions needed for the cell to function optimally. The human body needs to be kept at 37˚C for it to adequately maintain its homeostatic environment.

Organisms need optimal growth to carry out its specialized functions. These organisms undergo growth in all phases and multi cellular organisms through cell division accumulate growth. We all started as a single cell but have now grown to possess billions of cells in our human bodies as a result of the growth that took place. These growth experienced is dependent on anabolic pathways which through the build-up of large complex molecules such as DNA and Proteins which gives us desired growth.

Reproduction is one of the ways organisms replicate themselves to create new same organisms. This can be either sexual where there is a production of sperm and egg cells containing information shared equally containing their genetic information making these cells form a new entirely organism with full genetic information as donated by the parent organism.
Asexual reproduction occurs when single celled organism divides by itself to produce an entirely new organism of its own.

This is seen as organisms respond to stimuli or when there is an environmental change, this is known biologically as “irritability”. For instance, people seem to run when danger is been sensed so do plants and animals respond to changes in their individual environments and our bodies responding as well.

This is a definite end for all organisms after performing its various activities as they won’t continue to live for ever. This comes to play either by a dangerous change in environment, altering of its metabolism, or by dangerous toxins released into its environment which militates its biochemical processes and ultimately causes the death of the organism.


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