Session 12: Ch 29 post
Currently, research is being done on histamine receptors to treat inflammation. What aspect of histamines makes their receptors reasonable targets for research on anti-inflammatory substances?
Histamine plays a role in the inflammatory response by increasing blood vessel permeability.
What is the function of cell-mediated immunity?
It removes cells infected by pathogens.
How does the polio vaccine work?
It stimulates the immune system by using an attenuated form.
Why is it difficult to design a vaccine for viruses such as HIV and flu viruses?
New mutations constantly change viral proteins, making them hard to recognize.
What does a very low CD4 count for an HIV-positive patient suggest?
The patient's immune system has been badly damaged by HIV.
How are dead or damaged body cells removed?
They are ingested by phagocytes.
If one were to artificially stimulate a Toll-like receptor (TLR), what kind of application could this have in treating a patient?
This could stimulate an immune response, helping to fight an infection, or even a tumor.
Why is cell-mediated immunity required, given that your immune system can produce antibodies?
Viruses and other pathogens can invade the body's own cells.
If you didn't have functional memory cells, what kind of impact would this have on your immune system?
Your rapid response to previous infections would be lost.
What is an allergy, in physiological terms?
an overreaction to antigens
The surface of bacterial cells is covered with proteins that the human body can recognize as belonging to a foreign, invading microorganism. These molecules are collectively referred to as ______.
antigens
Where do lymphocytes originally form in the body?
bone marrow
Which proteins in the immune system can cut holes in the cell membrane of invading bacterial pathogens?
complement proteins
Which protein in the immune system seals off the site of infection?
fibrin
When a dendritic cell presents viral fragments as antigens, to which cell does it then bind?
helper T cell
Antigen-presenting cells (APC) are important in that they allow ______.
helper T cells to recognize a viral invader
After getting bitten by an insect, you notice that your skin has become red and swollen, has a localized fever, and is painful. Most of these symptoms are caused by the release of ______.
histamine
Mast cells produce ________.
histamine
Which two parts of the body store B cells and T cells and inspect fluids?
lymph nodes and spleen
Which of the following immune system cells can differentiate into a memory cell?
lymphocytes
Which of the following immune system cells can differentiate into a regulatory cell?
lymphocytes
Which of the following cells is a phagocyte that also presents fragments of bacteria to other immune system cells?
macrophage
Once vaccinated, you have had a primary exposure to specific antigens. If you ever encounter that antigen again, you will mount a rapid immune response because of ______.
memory cells
Which of the following immune system cells secrete antibodies?
plasma cells
Antibodies are powerful weapons in the body's defense against microorganisms. However, there are limits to what an antibody can actually do. Which of the following is NOT an action that an antibody can accomplish?
poke microscopic "holes" in a bacterial cell membrane, causing it to die
What nonspecific protection against external pathogens and invaders does the human body have on any surface exposed to the outside world?
skin
Where in the body do immune system cells learn to distinguish self from non-self?
thymus
Which gland in the body develops the lymphocytes involved in cell-mediated immunity?
thymus gland
Why is it important to have regulatory T cells as part of your immune system?
to act as a feedback mechanism to gear down the immune system