Terms in this set (16)
A harmless variant of a pathogen that stimulates a host's immune system to mount defenses against the pathogen
A procedure that presents the immune system with a harmless variant of a pathogen, thereby stimulating the immune system to mount a long-term defense against the pathogen
active vs passive immunity
Active immunity involves your bodies direct response to an unknown pathogen. This response is the production of antibodies specific to the antigen of a particular pathogen. This type of immunity is not immediate as it takes time to have create enough of the correct antibodies to fight the pathogen. And Passive immunity is an immune response which involves antibodies obtained from outside the body. An example of this is the antibodies a mother passes to her infant through her breastmilk
who created the first vaccine
Edward Jenner, smallpox
(small pox) you start with another virus that very similar to the virus you are trying to protect against. You use this virus and put it in your system, therefore your body creates antibodies that will recognize a very similar virus
(measles) you use a live-attenuated vaccine, which means that you need to alter a pathogen, so that it will invade cells in the body and use those cells to make many copies of itself. The altered virus must be similar enough to the original virus to stimulate and immune response, but not so similar that it brings on the disease itself.
An example of a vaccine made using this example would be the polio vaccine, the goal with this vaccine is to disable a pathogen's replicating ability while keeping intact its shape and other characteristics that will generate an immune response against the actual pathogen. When the body is exposed to the killed polio vaccine, its immune system will set up a defense that will attack any live polio viruses that it may encounter later
An example of a vaccine made using this example would be the tetanus vaccine, with this vaccine the goal is to condition the immune system to combat not an invading virus or bacteria but rather a toxin produced by that invading virus or bacteria.
An example of a vaccine made using this example would be the hepatitis B vaccine, in this vaccine, it makes use of just a small portion of a pathogen. For a virus, the vaccine can contain just a piece of the protein coat that surround the virus's DNA.
An example of a vaccine made using this example would be the HIV vaccine, the goal of these vaccines is to use a gene from a pathogen to generate an immune response. A gene contains the instructions to create a protein. With a genetic vaccine, small loops of DNA in the vaccine invade body cells and incorporate themselves into the cells' nuclei. Once there, the cells read the instructions and produce the gene's protein.
Why do you need a booster shot?
the dead vaccines don't last as long, and your immunity can wear off, and you will need another vaccine, or a booster shot
How does a vaccine work?
When antigens are detected, several types of cells work together to recognize and respond to them. The cells trigger the B lymphocytes to produce antibodies, which are specialized proteins that lock onto specific antigens. Once produced, these antibodies stay in a person's body, so that if their immune system encounters that antigen again, the antibodies are already there to do their job.
Vaccines work work the same way. They work by mimicking disease agents and stimulating the immune system to build up defenses against them. Vaccines look like a certain bacteria or virus to the immune system, but they don't make you sick.
Pathogens are covered with molecules called antigens that can trigger a specific immune response.
Vaccines expose the body to antigens similar to the antigens found on the pathogen. By acting like the specific pathogen, the immune system will be primed to respond with speed and strength if you encounter the actual pathogen in the future. Although antibodies can recognize an antigen and lock onto it, they are not capable of destroying it without help. That's the job of the T cells, which are part of the system that destroys antigens that have been tagged by antibodies or cells that have been infected or somehow changed.
Why does a plasmid need to be cut with the same restriction enzyme?
if two different DNA molecules are cut with the same restriction enzyme, both will produce fragments with the same complementary sticky ends, making it possible for the DNA to come stick back together
molecular scissors and glue
restriction enzymes are the scissors and the ligase is the glue
What is the process of DNA recombination?
plasmids, can be used to transfer fragments of genes into other organisms. The plasmid DNA must first be cut using a protein called a restriction enzyme. And the enzyme cuts the DNA at a specific sequence. When the enzyme finds the DNA sequence it breaks the DNA backbone, leaving overhanging ends, called sticky ends. When a piece of DNA is cut with sticky ends, it can match together with the complementary ends, and is pasted together with another enzyme called ligase. The plasmid, with its new gene insert can now be transferred to another organism.
What is herd immunity?
more individuals that are immune decreases the incidence of the disease and the occurrence of the pathogen. With greater number immunized, it is less likely that an unimmunized person will encounter the pathogen.