The body of a human being needs to have a defense mechanism of which it can be able to defend itself from foreign pathogens (germs and microorganisms). The composition of this system is made up of proteins, tissues and organs which have all been derived from the basic unit of the body i. e. the cell. The complexity of this system is able to relay information throughout the many different kinds of antigens that are able to block incoming agents or they are self antigens. Hence an imbalance of the immune means that one has been succumbed to an infection or an infection is thus setting in.
Research is also showing that we are all protected by the immune system which is able to shun the actions of unwanted antigens which have invaded our body system. But the advantage to the body is that there are defense barriers in every entry site to the host. Also the immune travels the body through the membrane cofactor protein and the decay accelerating factor which is killing all that is not needed but then they also attack the healthy cells too in this check. Therefore, the healthy cells rely on protective protein cover so as to avoid being hit (USA Today, 02/1993, p. 9).
Therefore, at any time the immune system needs to be is functioning best, the body functions need to be at an optimum level which is referred to us as homeostasis. This is therefore the steady state that the body needs to be in so as to be functioning well. The body is marvelously organized in that the grouping of cells brings about the tissue cell, tissues bring about the organs (which cannot be able to work on their own), and the organs therefore compose to bring about the system. The system therefore, gives the various activities such as: • Filtration by the excretory system,
• Body support and protection of the internal organs is aided by the skeletal system, • Distribution of nutrients by the aide of the circulatory system, • Breathing in and out of air by the respiratory system etc. The body can be able to interact with the external environment despite the size, weight and the metabolism rate of any given organism. The internal environment of the animal is kept at a regulated level despite the external environment’ interactions may vary in relation to the internal environment the regulation is through the homeostatic mechanism that relies on negative feedback.
The negative feed back needs a receptor, a control center and an effector. When a receptor detects for instance a change in temperature the control center receives information about the change from the receptor and then relays an appropriate response by the effector (Campbell, Reece & Mitchell, 1999). THE CELL Simply it’s the fundamental basis of any living thing, which is separated by a plasma membrane from the environment. Without the cell there is no life that will come about. THE TISSUE The structural unit that brings about life when grouped up gives us the tissue.
But the tissue only is viable only when the cells that have come together do have a common function and structure. A single animal despite the size has hundred kinds of tissues which are mainly divided in to the following: • Nervous tissue – involved with the nerve impulse that are sensed stimuli after which they are transmitted to a different part from where the impulse came from. This tissue has dendrites with long extensions and axon which are used to send stimuli from the point of application to the end; • Connective tissue – binds and supports other tissues.
This tissue is not arranged in any manner because they are mainly scattered in many different ways, attached to an extra cellular matrix; • Muscle tissue – consists of muscle fibers which cause body movements that in turn do a specific function either lifting or pulling, and • Epithelial tissues – this tissue is highly packed to give a perimeter to the body from external foreign organisms, also lines cavities and many kinds of body organs. The packing of the tissue may look like a mat called the basement membrane which arises from the extra cellular material. Their shape and the stack of layers give the categories of the tissue.
THE ORGAN The body function of any animal is capable to function where the composition of the tissue cells does bring up the organ formation. This is only a part that can only work when the body possesses the organ system. THE ORGAN SYSTEM This is the general composition of the cell, tissue, organ and the organism. The organ systems present in any organism are all interdependent. This is a system that is only suited because the rest of them are the primary units that enable the body to possesses this kind of system. The organ system can only be fit to work if and only if the organs are functioning.
There has to be a coordination of all the organs so that the organ system can possibly function. For instance, when our body takes in nutrients from the digestive tract the rest of the body does get the nutrients by the help of the circulatory system. But blood is pumped through the respiratory tract and the absorption of O2 which is together associated by the respiratory system. All organisms despite their conformation they all possess an organ system which is a coordinated living whole that is greater than the specific parts that bring about the organ systems.