Question

Which system protects against injury and the introduction of foreign microorganisms or toxins into the body?

1) Respiratory system
2) Circulatory system
3) Digestive system
4) Immune system

Answer 1

The immune system, including its innate and adaptive components, protects the body against foreign microorganisms and toxins.

Step-by-step explanation:

The system that protects against injury and the introduction of foreign microorganisms or toxins into the body is the immune system. The innate immune system provides the first line of defense with physical and chemical barriers that work against all pathogens. When these barriers are breached, the adaptive immune system, which has a specialized and memory-based response, targets and destroys specific pathogens that threaten the body's health. This system includes lymphatic system components that mount a defensive immune response against invading pathogens.