Mastering Biology Chapter 43

How is a viral antigen, like EBV, recognized by T cells?

An antigen fragment is presented within class I MHC to the T cell receptor

What major advantage is conveyed by having a system of adaptive immunity?

It enables rapid defense against an antigen that has been previously encountered

Which of the following statements explains why your class mate does not exhibit symptoms of EBV infection?

Memory T cells quickly recognized the virus upon the second exposure and destroyed the virally infected cells

___ are cells of the mammalian innate immune response that help destroy tumors

Natural Killer cells

Mucus occurs in both the respiratory and digestive tracts. What is its main immunological function?

Physically trapping of pathogens

___ are receptor molecules on mammalian cells that recognize macromolecules that are present in or on certain groups of pathogens

Toll-like receptors

You and a friend were in line for a movie when you noticed the woman in front of you sneezing and coughing. Both of you were equally exposed to the woman's virus, but over the next few days, only your friend acquired flu-like symptoms and was ill for almost a week before recovering. Which one of the following is a logical explanation for this?

You had an immunological memory of that virus

A patient complaining of watery, itchy eyes and sneezing after being given a flower bouquet as a birthday gift should be first treated with

antihistimines

A newborn who is accidentally given a drug that destroys the thymus would most likely?

be unable to differentiate and mature T cells

The ability of some viruses to remain inactive(latent) for a period of time is exemplified by

herpes simplex virus whose reproduction is triggered by physiological or emotional stress in the host

Inflammatory responses typically include

increased activity of phagocytes in an inflamed area

A boy falls while riding his bike. A scrape on his hand almost immediately begins to bleed and becomes red, warm, and swollen. What response is occurring?

inflammatory response

Acidity in human sweat is an example of _____.

innate immunity

innate immunity

is the first, and most general, mechanism of protection against pathogens

The cells and signaling molecules involved in the initial stages of the inflammatory responses are

mast cells and histamines

___ is the characteristic of adaptive immunity but not innate immunity

memory

A certain cell type has existed in the blood and tissue of a vertebrate host's immune system for over 20 years. One day, it recognizes a newly arrived antigen and binds to it, subsequently triggering a secondary immune response in the body. Which of the following cell types most accurately describes this cell?

memory cell

What type of immunity is associated with breastfeeding?

passive immunity

Naturally acquired passive immunity can result from the

placental transfer of antibodies

Yearly vaccination of humans for influenza viruses is necessary because

rapid mutation in flu viruses alters the surface proteins in infected host cells

Immunological memory accounts for

the ancient observation that someone who had recovered from the plague could safely care for those newly diseased

Lymphocytes mature in the

thymus and bone marrow