An organism’s first line of defense against attack by an invader such as a virus or bacterium is usually
A. to flee or hide
B. its body wall
C. a specific immune response
D. a nonspecific immune response
Answer:B
An organism’s first line of defense against attack by an invader such as a virus or bacterium is usually
A. to flee or hide B. its body wall C. a specific immune response D. a nonspecific immune response