Once almost a rite of childhood, tonsillectomy (surgical removal of the tonsils) is now rarely performed. Similarly, while ruptured spleens were once routinely removed, they are now conserved whenever possible. Why should these lymphoid organs be preserved when possible?

More than one choice may apply.

Where exactly does an antigen bind to an antibody molecule?

Identify the structures of the lymphatic system in the following diagram.

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a. ___

b. ___

c. ___

d. ___

e. ___

f. ___

g. ___

h. ___

i. ___

j. ___

k. ___

l. ___

m. ___

n. ___

o. ___

p. ___

q. ___

A friend tells you that she has tender, swollen 'glands' along the left side of the front of her neck. You notice that she has a bandage on her left cheek that is not fully hiding a large infected cut there. Exactly what are her swollen 'glands,' and how did they become swollen?