Which statement best contrasts innate with adaptive immunity?

Which statement best contrasts innate with adaptive immunity?

• A. Innate is rapid and nonspecific; adaptive is slow and specific with memory.
• B. Innate is slower and specific; adaptive is rapid and nonspecific.
• C. Adaptive immunity has no memory.
• D. Innate and adaptive are the same.

Answer: (A)

Timing, specificity, and memory define the difference between innate and adaptive immunity. The innate system acts quickly as the first line of defense and responds in a nonspecific way to broad pathogen features, using barriers, phagocytes, natural killer cells, and complement. The adaptive system takes longer to develop after exposure, uses highly specific receptors to target particular antigens, and generates memory cells that enable a faster, stronger response upon re-exposure. This makes the statement describing innate as rapid and nonspecific and adaptive as slow and specific with memory the best description. The other options misstate timing, specificity, or memory, and the two systems are not the same.

Timing, specificity, and memory define the difference between innate and adaptive immunity. The innate system acts quickly as the first line of defense and responds in a nonspecific way to broad pathogen features, using barriers, phagocytes, natural killer cells, and complement. The adaptive system takes longer to develop after exposure, uses highly specific receptors to target particular antigens, and generates memory cells that enable a faster, stronger response upon re-exposure. This makes the statement describing innate as rapid and nonspecific and adaptive as slow and specific with memory the best description. The other options misstate timing, specificity, or memory, and the two systems are not the same.