Which makes viral infections difficult to defeat

(a) the immune system must attack the body’s own cells

(b) macrophages work slowly

(c) viruses live outside of cells

(d) viruses are attacked by a nonspecific immune response

Vegetation that grows along the floors of tropical and temperate forests is called undergrowth. how is the undergrowth of a tropical rain forest most likely to differ from the undergrowth of a temperate forest? a. a tropical rain forest's undergrowth most likely experiences periods of dormancy during colder weather. b. a tropical rain forest's undergrowth most likely experiences periods of dormancy during rainy weather. c. the undergrowth of a tropical rain forest most likely requires less sunlight. d. the undergrowth of a tropical rain forest most likely requires more sunlight.

What are the doorways into and out of cells, attached to the membrane, and built in the rough er.

The tubes transporting minerals and water upward are called ?