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Question:i have to write a biology report and im getting confused on the real difference between passive and active immunity. please help :)

Answers:Active immunity is when your body "actively" makes the necessary antibodies after exposure to an antigen. Passive immunity occurs when the antibodies (produced elsewhere) are administered; eg, the antibodies produced by a horse in response to snake venom is used in an emergency antivenin kit. If bitten by a snake, you are given a shot of antibodies made by the horse. This kind of immunity doesn't last very long. Both kinds of immunity can be either natural or artificial, depending on where the antigen or antibody comes from from.


Answers:Active immunization involves your body making antibodies to something... so, if you get infected with strain X of a cold virus, and you make antibodies to strain X, you're "actively immunized". Passive immunization is when antibodies from another source are put into you... a common example of this is antivenin for snake bites--the antivenin is a suspension of antibodies against the toxic components of the snake's venom. Another huge difference: because your body makes antibodies in active immunization, you're immune to the antigen (in my example, strain X) forever, while passive immunization only gives you immunity for the short time the antibodies are in your bloodstream.


Answers:Passive immunity is rapid, strong, and temporary, and can be obtained naturally (antibodies passed on from mother to infant) or artificially (antibodies injected by a doc to protect against something specific, like Hepatitis B). Active immunity is much more long-lasting, although how long varies depending on what you're talking about. Again it can be natural (get infected with the herpes virus that causes chickenpox, thereafter you're resistant to chickenpox) or artificial (get a chickenpox vaccine). Once the bug is in you, your immune system generates a defense against it, including but not limited to antibodies. For the initial infection, an active immune response is slower than passive, but for subsequent infections (say two years later you get infected with chickenpox again) the response is very quick and strong -- so much so that you don't even show signs of having chickenpox. Rowlfe I think you're confusing this with innate vs. adaptive immunity.


Answers:Active immunity is one developed by the body itself in the form of antibodies in response to the introduction of disease causing antigens. For eg. In vaccination attenuated disease causing germs are injected into the body to trigger the formation of the required antibodies which would provide immunity to the body when it actually comes in contact with the actual pathogens. It is similar to having money in the bank in case of emergencies. In other words the body defence mechanism actually participates in providing the immunity. Passive immunity, is the immunity derived by the introduction of the antibodies from a source other than a person's own body. Eg. The immunity derived by a new born baby through its mother's milk.