What are the differences between innate and acquired immunity?

Innate immunity is present at birth, while acquired immunity develops over time through exposure to pathogens.

Innate immunity is the first line of defence against pathogens and is present at birth. It includes physical barriers such as skin and mucous membranes, as well as chemical barriers such as enzymes and antimicrobial peptides. Innate immunity also involves immune cells such as macrophages and natural killer cells, which can recognise and destroy pathogens.

Acquired immunity, on the other hand, develops over time through exposure to pathogens. It involves the production of specific antibodies and immune cells that can recognise and respond to particular pathogens. Acquired immunity can be either active or passive. Active immunity is generated by the body's own immune system, while passive immunity is acquired from another source, such as through the placenta or breast milk.

One key difference between innate and acquired immunity is their specificity. Innate immunity is non-specific, meaning it can respond to a wide range of pathogens, while acquired immunity is highly specific, targeting particular pathogens. Another difference is their memory. Innate immunity does not have memory, meaning it cannot recognise and respond more effectively to pathogens it has encountered before. Acquired immunity, however, has memory, allowing it to mount a faster and more effective response to pathogens it has previously encountered.

In summary, innate immunity is present at birth and provides non-specific defence against pathogens, while acquired immunity develops over time and is highly specific, with the ability to remember and respond more effectively to pathogens it has encountered before.