El Sistema Inmunologico Humano.
Understanding the Immune System's Response to Infections
The Role of the Immune System
- The immune system learns to recognize infections, with each germ posing a potential threat. However, immunity begins only when germs enter the body.
- Various physical defenses exist against infections, such as eyebrows and eyelashes that trap airborne bacteria, while sweat, tears, and mucus help wash them away.
Mechanisms of Defense
- Saliva contains lysozyme, an enzyme that targets bacteria; despite their small size, salivary glands produce nearly 18 liters of saliva daily.
- When pathogens breach external defenses, they exploit weaknesses in immature immune systems. Viruses can infect skin cells and replicate rapidly before causing symptoms like rashes.
Immune Response Activation
- White blood cells attack infected cells by injecting toxic proteins to eliminate both the cells and viruses. Skin blisters indicate ongoing battles between the immune system and invaders.
- While unpleasant, contracting diseases during youth is crucial for developing robust immune systems. The body creates memory molecules (antibodies) against viruses.
Importance of Antibodies
- As individuals age, their bodies produce antibodies independently rather than relying on maternal antibodies. This allows for immediate recognition of previously encountered viruses upon re-exposure.
- White blood cells act swiftly to neutralize threats before they can take control again; this highlights why childhood is an optimal time for vaccinations.