Question

All of the following are true regarding NK cells EXCEPT

Select one:

a. they are found in tissues of the lymphatic system.

b. they have the ability to kill infected body cells and some tumor cells.

c. they are a type of lymphocyte.

d. they release toxic substances that cause cell lysis or apoptosis.

e. they destroy infected body cells by phagocytosis.

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Which of the following antibodies is a pentamer?

Select one:

a. IgE

b. IgM

c. IgD

d. IgA

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When haptens attach to carrier molecules, an epitope forms on hapten which then can be bound to antibody.

Select one:

True

False

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A chill is a sign that

Select one:

a. the metabolic rate is decreasing.

b. body temperature is not changing.

c. body temperature is rising.

d. body temperature is falling.

e. blood vessels are dilating.

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Biofilms provide pathogens with an adhesion mechanism and aid in resistance to antimicrobial agents.

Select one:

True

False

Answer 1

1. Option E is correct.
NK cells destroy virus-infected or tumor cells by inducing apoptosis. They are not professional phagocytic cells. However, there are few reports that suggest that they can also serve as phagocytic cells.

2. Option B is correct.
IgM is the pentameric antibody. It contains 10 antigen binding sites.

3. True.
Haptens are incomplete antigens. their antigenicity is increased by providing them with a carrier molecule.

4. Option B is correct.
A chill is a sign that the body temperature is rising.

5. True
Biofilms provide a selective advantage to microbes for adhesion as well as antibiotic resistance.