21. The Immune System

An anesthesia technician is advised that she should be vaccinated against hepatitis B, which is caused by a virus. She is given one injection and is told to come back for a second injection in a month and a third injection after 6 months. Why is this series of injections necessary?

Describe the specific roles of helper, regulatory, and cytotoxic T cells in normal cellular immunity.

Differentiate between a primary and a secondary immune response. Which is more rapid and why?

More than one choice may apply.

Which of these antibody classes is usually arranged as a pentamer?

a. IgG

b. IgM

c IgA

d. IgD

Your friend tests her snake-wrangling skills on an eastern diamondback rattlesnake, and is bitten and envenomated (injected with the snake's venom). In the emergency department, doctors administer the antivenin CroFab, which contains antibodies to the toxins in snake venom. Is this an example of active or passive immunity? Will this confer any lasting protection to your friend?

The major histocompatibility complex (MHC)

(a) Is responsible for forming lymphocytes

(b) Produces antibodies in lymph glands

(c) Is a group of genes that codes for human leukocyte antigens

(d) Is a membrane protein that can recognize foreign antigens

(e) Is the antigen found on bacteria that stimulates an immune response

Each class of antibody is specifically defined by its

How do antibodies help defend the body?