View the animation below, then complete the quiz to test your knowledge of the concept.

1	Bacterial and viral antigens are presented to helper T-cells by
	A)	macrophages.
	B)	B cells.
	C)	plasma cells.
	D)	activated helper T cells.
	E)	cytotoxic T cells.
2	Helper T-cells interact with target cells by recognizing
	A)	antigens only.
	B)	MHC proteins only.
	C)	antigen-MHC protein complexes.
	D)	either antigens or MHC proteins.
	E)	neither antigens nor MHC proteins.
3	Helper T-cells stimulate
	A)	cytotoxic T-cells to be become helper T-cells.
	B)	cytotoxic T-cells to be become B-cells.
	C)	B cells to become cytotoxic T-cells.
	D)	B cells to become helper T-cells.
	E)	B cells to become plasma cells.
4	Helper T-cells interact with Class I major histocompatibility complex (MHC) proteins.
	A)	True
	B)	False
5	Plasma cells produce antibodies.
	A)	True
	B)	False