Lymphocytes are divided into two vital divisions which are T-cells and B-cells, Lymphocytes are a clear liquid that carries only the white blood cells around the body it is very similar to blood Plasma cells. The lymph flows through all parts of the body picking up the fluid around cells and carrying it back to large veins near the heart. The lymph also carries the white blood cells to the areas in the body that need it. Some bacteria and viruses that sometimes enter the body are then collected by the lymph and then filtered out by the lymph nodes also known as glands. This is why when you go to the doctor they check the lymph nodes in your neck and under your arms if they are swollen to check if you have an infection. However one way to tell that lymph nodes are working, and is getting rid of the bacteria and viruses that enter your body is when your neck or underarm is swollen.
Most immune systems are white blood cells, called Leukocytes. Leukocytes are white blood cells which are a part of this defense which invades and destroys substances and infectious organisms that cause disease, the one common type are
an active natural immunity only occurs when an infection is present in the body the natural immunity becomes active, this is because the lymphocytes become activated due to the exposure of antigens and the pathogens on its surface, this happens through a serious of steps which is called the immune response. An immune response is the body’s response to a pathogen or a foreign invader this is usually a very defensive reaction and causes swelling and inflammation, this reaction takes place in order to stop the foreign invader from harming the body, this response tales place when a white huge blood cell which is called a ‘phagocyte’ helps and increases the immune defences. Phagocyte is a biological cell which invades micro organisms and other cells which may be harmful to the body, this is done thorough a special process called phagocytes. Macrophages also perform the same functions they also invade dead cells and other foreign organisms and then engulf them and act like scavengers.
However a pathogen is a substance a gene which produces and causes many diseases and micro organisms in the body, it is a infectious organism however the human body comes into direct contact with pathogens everyday however the immune system recognises it as a intruder and destroys the infectious organism which then is no longer harmful and isn’t capable to cause harm to the body any longer, when a person comes into contact with a pathogen his is considered as exposed, however when the pathogen enters the body and has produced a bacterium in the body this is then considered as being infected by a pathogen and this is when the natural immunity stimulates and then reacts.
The immune system
Bacteria’s are found all around the body and exist under every condition of life which replicates every second. Virus is another concept of organisms, which reproduce but don’t respire or nor do they move many are pathogenic; they are harmful and are capable of causing diseases. Fungi is as well as a bacteria and are most often associated with plants, it is truly pathogenic and is also capable of producing infectious microorganisms however Memory cells are made to invade and attack those foreign cells and then engulf it, this means to destroy it.
The human body's non specific defence
The skin as an organ of defense _ In the immune system the skin is the first line of defense, another term for the skin is the integument. The skin is the largest organ of the body and it is also the great importance in the defence of the body, the skin contains glands which are also known as sebaceous glands. Just like your skin acts as a barrier to germs this is how the thick mucus membranes act which line your mouth, throat, lungs and bowel .Your nose, mouth and eyes are the next point of which the bacteria may attack you, this is why there is mucus that is made in the nose, throat and lungs that traps the bacteria, viruses and dust, which you may breathe in. The saliva in your mouth and the tears in your eyes have special enzymes which break down the cell walls of many bacteria and viruses, this is how the mouth and eyes act as an defence for the immune system.There is acid in your stomach that kills most of the germs you may take in with your food, and then the stomach starts to digest the food. There is a thick layer of mucus around the stomach to stop the stomach from letting the acid digesting itself.
Vaccination and Immunization
Immunisation is a vaccination which helps people improve their immunity to the immune system and stop the body from getting developing particular diseases and to protect people against serious illnesses. There are many types of vaccines for many different diseases, a vaccine is an injection given to the body to build up immunity and make the person less vulnerable to pathogenic diseases. The effect immunisation has on the body is that once the body is immunised it is more capable to fight the foreign invaders which get into the body. Immunisation programmes vaccinate against specific diseases such as ,, the , and .
Active and passive immunity
Natural immunity Active natural immunity only occurs when an infection is present in the body it becomes active becomes it becomes the lymphocytes become activated due to the exposure of antigens and the pathogens on its surface.
Artificial immunity Active artificial immunities are when it’s not natural, so for instance when it is injected or taken antigens by mouth, in other words when it is antigens are introduced into the body deliberately.
Active natural immunity Active natural immunity occurs when someone is exposed to a harmful pathogen or antigen, for instance when children get chicken pox and then get cured and never get it again because the immunity was natural and the immune system now recognises the disease and prevents it from happening again. Exposure to infection
Active artificial l immunity Active artificial immunity occurs when a specific produced antigen is intentionally put into an individuals system, the procedure for this is called vaccination, the vaccine is to stop usually targeted to a specific illness and targeted to improve immunity and stop it from getting involved with a specific illness. Artificially by vaccination
Passive natural immunity Passive natural immunity occurs through natural means for instance a relationship between a mother and the child, when the antibodies are passes from her body to the baby’s body through breast feeding; this provides a short term protection for the baby after it has been born, another way antibodies are passed from body to body is through the placenta and into the fetal blood.
Passive artificial immunity Passive artificial immunity is made use of when short term protection is needed immediately, this is done by taking out antibodies from one individual and inserted into another, and the term antiserum is used for this procedure.
The difference between active and passive immunity _ The differences between active and passive immunity are that active immunity originally produces the antibodies in order to invade the antigens; it becomes immune naturally due to the primary immune response. However passive immunity is when antibodies are transferred from one individual to another which then provides short term passive immunity, it becomes immune artificially. Immunisation
Immunity is defined as the protection which is developed in the body against further damage by an organism or toxin, so basically this means that immunity means that you are protected against something, for example many children may become infected with bacteria or viruses which eventually leads to serious illnesses, however some of these organisms may also produce toxins which may result in serious damage however the body then develops resistance against further infections by the same organism or against the toxin which these organisms produce , this protection is called immunity.
